300mm Equipment Standards and Guidelines

Stephen Sumner, Intel Corporation, William Fosnight, Asyst Technologies -- Semiconductor International, 3/1/1999

A bstract

The development of 300mm Semiconductor Equipment and Materials International (SEMI) began just over three years ago and continues today. This paper provides a status and overview of the current 300mm physical interfaces and carriers SEMI standards and related I300I/J300 Guidelines, how they apply to 300mm equipment, and how they relate to and cite each other. In order to provide insight into the state of SEMI standards, the background and significant details of each of the 300mm SEMI Physical Interface and Carriers (PIC) standards are explained. This paper is intended to serve as a valuable resource to those who need to understand and comply with the SEMI automation interface and carrier standards, but who have not directly participated in their development. The status of testing 300mm equipment compliance to standards and guidelines, new standards activities, proposed standards activities, and industry needs are also presented.

Introduction

The last three years have seen a significant and unprecedented amount of activity in SEMI Standards development, mostly owing to an industry conversion from 200mm to 300mm wafer manufacturing. Although wafer size changes in manufacturing are not new to the industry, such sweeping global standardization including equipment interfaces for carriers and automated and manual delivery systems is a first. 'Interoperability' being the key word for 300mm standards and guidelines, equipment suppliers are experiencing growing pains not only from process changes, but also from the need to comply to myriad automation interface guidelines and standards which intend to make every process equipment interface identical in the eyes of wafer carriers and delivery systems.

Not only have tremendous strides been made in equipment standardization, but a quantum leap in international cooperation has been made through the efforts of SEMI and consortia such as I300I (International 300mm Initiative) and J300 (Japan 300mm Conference). While the internationalization of the standards process provides equipment makers with a unified voice of guidance world-wide, it is not an easy journey, and the leadership of key individuals representing not only suppliers and device makers, but countries from all over the world, is truly applauded. Many of the standards efforts cultivated over the past three years are gradually producing fruits in the form of usable SEMI standards for carriers and physical equipment interfaces. Recently, standards are seeing less change and having a chance to solidify and prove themselves, will highlight areas of need and improvement. This temporary lull in activity is an excellent opportunity to reflect upon what has been accomplished, what is yet to be accomplished, and finally how to make sense of it all.

This paper intends to provide the reader with knowledge needed to successfully understand and use the SEMI standards for Physical Interfaces and Carriers. It's hoped that this article is one that gets clipped and referenced by those who have to consider SEMI compliance. This paper is an attempt to explain SEMI standards, and should in no way be interpreted as a substitute or short cut for their content.

Overview of Current 300 mm Physical Interfaces and Carriers SEMI Standards

SEMI is a global organization that is divided into 3 main regions: Europe, Japan, and North America. Traditionally, standards were written, adjudicated, and subscribed to regionally with limited international activity. However, with the increasingly global nature of business in general, the semiconductor industry decided to take lead in embracing international consensus to ensure sound fundamental engineering bases are applied to SEMI standards. Apart from SEMI, which oversees development of and publishes standards for reference, 300mm conversion has given birth to two major international consortia: I300I and J300.

I300I, spawned from SEMATECH (an U.S. consortium formed in 1987) was opened to participation not only from American device makers, but also by European and Asian IC makers. In total, 13 companies (3 European, 3 Korean, 1 Taiwanese, and 6 U.S.) came together to guide process equipment development and participate in standards activities. In 1998, I300I was expanded to International SEMATECH which includes lithography, environmental health & safety, standards, etc. J300 is the equivalent Japanese SELETE body to I300I. These groups manage equipment and factory development aspects affected by a wafer size change, not issues faced around technology changes to reduce chip size or increase transistor density. I300I/J300 charters are to establish the development parameters for 300mm process, metrology, and automation equipment (please see Global Joint Guidelines, http://www.i300i.org/public/guide.htm). This complements SEMI's charter, which is to provide mechanical specifications for fundamental features of 300mm equipment, interfaces, and carriers which do not limit innovation among products, but ensure fundamental equipment features that aid suppliers and IC makers alike to integrate products into an interoperable symphony of equipment.

Further information and SEMI Standards documents may be obtained through: SEMI North America (Headquarters), 805 East Middlefield Road, Mountain View, California 94043-4080 USA, phone: 650.964.5111, or http://www.semi.org/

Background and Details of SEMI 300 mm Mechanical Standards

TThis section discusses the background and details of each of the newly developed 300mm SEMI equipment (E) standards. Communication and software standards tend mostly not to be wafer size dependent, but a few standards are being updated to address the carrier architecture and management.

Before delving into the details of each standard, it is important to explain the approach and philosophy by which the 300mm standards have been developed. Traditionally, SEMI specifications strictly specify many, if not all, of the dimensions of the equipment covered (such as the 200mm cassette). Attacking 300mm, a different approach was chosen. Only the mechanical interfaces between equipment are strictly specified. Furthermore, when defining the features of the interfaces, only one side of the interface is strictly specified; allowing innovation by the designer of the non-specified side (for example the SMIF interface features are specified, but not the pod door with which it mates.) Features within the equipment, which do not physically interface with other equipment, are bounded only by minimum and maximum volumes; thereby defining exclusion volumes in which the features and/or devices may exist.

All 300mm SEMI standards are 'Provisional.' This indicates that proven designs or data were not available when the standard was composed and, as a result, the standard may change once designs are tested.

SEMI E1.9 Provisional Mechanical Specification for Cassettes Used to Transport and Store 300 mm Wafers was the first 300mm standard developed by the SEMI Physical Interfaces and Carriers Committee. It was also the first standard to test the aforementioned philosophy. Although by title it specifies 300mm open cassettes, it has a broader scope as will be explained. Within this standard, the most basic carrier requirements such as wafer capacity and the pitch between wafers are specified.

Carrier capacity was one of the first main issues of debate. Clearly, two schools of reasoning exist: one which favors a smaller carrier capacity cites fab cycle time, ergonomics and risk management as key drivers for decreasing the capacity from 25 wafers used 200mm applications. On the other hand, those favoring a larger lot size cited throughput, storage density, and fewer carrier transport transactions as key motivators. In the end, the SEMI standard was written to allow both the traditional (25 wafers), and smaller carrier (13 wafers) capacities. To further complicate the carrier capacity issue, the number of wafers constituting the small and large capacity was debated. The selection of product lot sizes of 12 and 24 plus one extra slot for a test wafer seemed quite logical based on the product wafer divisibility. However, suppliers of ion implanters who need to load smaller batches into their equipment pointed out that many IC manufacturers will likely use all 13 or 25 slots for product wafers. Nevertheless, after further debate carrier capacity options of 13 and 25 emerged. At this time, nearly all integrated circuit (IC) manufacturers opt for the larger lot capacity. It was decided to specify that wafers be stored and transported in the horizontal orientation while in the carriers. This decision was grounded in the percentage of equipment that processes the wafers in a horizontal orientation. Presenting the wafers in their processed orientation reduces the automation requirement of equipment. An issue of considerable debate was pitch between wafers in the carrier. 200mm wafers are separated at a pitch of 0.25-in (6.35mm). For 300mm, wafer pitches ranging from 3.2mm to 15mm were proposed. After several meetings and much debate, a few equipment suppliers presented tolerance stack-up calculations for review by the committee. The definitive evidence lie in the case of a vacuum end-effector; calculations showed that the minimum pitch should be no less than 10mm. The larger wafer pitch was later selected after review of all assumptions used in the analyses were presented and also justified based on the possible requirement of edge-only contact by end-effectors for 300mm wafers. While carrier capacity and pitch are keystone specifications, E1.9 also specifies other dimensions which form the basis for 300mm wafer handling including:

• positions in which wafers may be inserted and retrieved

• volume in which wafer support features may exist (also defining end-effector exclusion zones)

• features on the bottom of the cassette for cassette placement detection (called sensor pads)

• information pad features on the bottom of the cassette for determination of carrier type, capacity, and process designations such as pre/post metalization (called info pads.)

All features mentioned thus far are also required in the 300mm form of the SMIF pod, known as a Front-Opening Unified Pod (FOUP). Additional features specified in E1.9 which pertain only to 300mm cassettes include:

• optical wafer sensing paths, robotic handling features

• identification tag areas

• conveyor rails

• fork-lift pick-up areas.

Nearly all 300mm IC manufacturers have chosen the FOUP as their 300mm carrier architecture. While E1.9 suggests it specifies cassettes, it is important to remember that it contains all specifications for FOUP wafer supporting features, sensor pads and info pads.

Equipment suppliers should pay particular attention to SEMI E1.9 when designing wafer handling automation, developing end-effectors, and locating carrier sensors (if building their own loadport). Note: End-effector designers should also consult the 300mm cluster tool module interface specification (E21.1) as applicable.

SEMI E15.1 Provisional Specification for 300 mm Tool loadport is the 300mm version of E15 that defines the height, position, and clearances around 200mm process equipment loadports. Although E15.1 had a good springboard standard in E15, it has taken the longest to reach maturity and quasi-stability due to the need for higher levels of interoperability. One primary dimension E15.1 provides is the loadport height, specified as 900mm (same as 200mm). Clearances around the carrier at placement are 30mm to the front (equipment side) and 75mm to each side (to allow sufficient space for manual loading using side handles). The spacing between two adjacent ports is specified as dimension S. However, dimension S was not settled upon until the overall width of the carriers (with and without side handles) was defined in SEMI E47.1. Additionally, a few Japanese companies want equipment optimized for open cassettes. As a result, S was ultimately assigned three values: S3420mm for open-cassette-only equipment, S3475mm for equipment to be used with handle-less FOUPs, and S3505mm for FOUPs with manual side handles. It is recommended that equipment suppliers select S3505mm if they want their equipment to be compatible with all carrier alternatives.

Another issue, which kept E15.1 in flux, was the advent of equipment internal buffers. E15 specifies that a clear chimney be kept open above the loadport all the way to the ceiling. However, it was realized that the space above a loadport might be used for carrier storage in optimized buffer configurations. Nonetheless, it is necessary to still provide a loadport with overhead access for loading by overhead transport (OHT) systems. As a result, three variations of E15.1 loadports are now included in the standard. Equipment suppliers should pay careful attention to the I300I Guidelines in order to understand which types of loadports are required.

In October 1997, additional constraints on loadport dimensions aimed at facilitating interoperability among various loadport designs were added. Dimension D1 specifies the distance from the carrier placement center-line to the space just above the FIMS-port to be 200+10/-4mm. Previously this dimension was only guided by leaving 30mm clearance in front of a FOUP (which is 165.5 mm from its centerline to the front of its door). Additionally, dimension D was tightened to be 245+5/-5mm instead of £250mm. This is believed by some to add unnecessary footprint to the front of the loadport, but was driven out of IC makers' need for consistency and uniformity of the loadport fronts within the fab when installed to a wall. Japanese proponents cited the fixed D dimension as being required for allowing space for safety-shields and doors on equipment..

E15.1 may easily be one of the most complex standards and should be closely studied and considered by process equipment suppliers. The E15.1 loadport guides the entire front-end layout of equipment including loadport placement and orientation, and carrier loading clearances. Items such as light towers, user interfaces, and front panels are all to be considered when allowing for the clearances required in E15.1.

SEMI E47.1 Provisional Mechanical Specification for Boxes and Pods Used to Transport and Store 300 mm Wafers was developed by the Physical Interfaces and Carriers committee soon after the open cassette standard (E1.9). It became apparent very early in the standards development process that most 300mm fabs would be opting for closed carrier solutions required by the I300I commitment to minienvironment equipment. At the time this standard was written, it was not clear whether IC manufacturers would select bottom-opening or front-opening SMIF pods. I300I decided shortly thereafter to delete this variable and selected the front-opening architecture based on its compatibility with open cassettes and concerns that much heavier payloads would be in danger during overheard transport. Nevertheless, both bottom- and front-opening pod maximum dimensions are included in this standard. E47.1 also refers to pods containing removable cassettes and non-removable cassettes. A non-removable cassette pod is one in which the cassette is fixed within the pod and is not available to be retrieved by the process equipment. While the idea of a non-removable cassette raised concerns from batch process equipment suppliers, IC manufacturers desired this configuration within their fabs. The front-opening non-removable cassette pod was later named the FOUP.

E47.1 has two basic purposes: it governs the over-all dimensions of the pods, and it strictly specifies all features which may interface with factory automation. These factory automation interfaces include a top 'mushroom' automation handle, conveyor rails located on the bottom and rear, fork-lift rails located on the bottom, and soon possibly side automation flanges. Side automation flanges were included in an early approved version of the ballot, were deleted based on being unnecessary, and are presently being reballoted for use with Person Guided Vehicles (PGVs) and Automated Guided Vehicle (AGVs).

Process equipment suppliers are not directly affected by E47.1 unless they are manipulating the carriers within their equipment; such as in the case of an equipment internal buffer. In this case, E47.1 provides the maximum dimensions of the pod and its automation features.

SEMI E57 Provisional Mechanical Specification for Kinematic Couplings Used to Align and Support 300 mm Wafer Carriers was developed in parallel with SEMI E1.9. E57 specifies the loadport side of the carrier to loadport registration. At 200mm, an 'H-bar' configuration was used to register cassettes to loadports. The 'H-bar' configuration proved useful in allowing standard cassettes to be developed, but by nature of its design, it does not prescribe known points of contact between the cassette and loadport and relies upon a tolerance in the x-y plane to allow non-interfering placement. As a result, the 'H-bar' has approximately ±0.25mm imprecision in x,y, and z directions. The kinematic coupling approach was first proposed by Dr. Alex Slocum of MIT as means to provide a more repeatable registration means while allowing lead-in capability for automated loading [ref].

The kinematic coupling consists of three rounded pins that mate with three radial grooves on the bottom of the carrier (E1.9) to define six points of contact. The six points of contact uniquely constrain the carrier in all six degrees of freedom. The kinematic coupling has been measured to be precise to less than 0.1mm in the x,y and z directions. The benefit of defined points of contact also raised concerns whether these points of contact would wear quickly, leading to both inaccuracy and particle generation. Experiments conducted in the US and Japan found that the kinematic couplings wore much less than 0.1mm over their lifetime. Additionally, any particles generated by wear are outside of the wafer environment in the 300mm closed carrier SMIF approach.

The precise shape and locations of the kinematic pins are detailed in E57. The top of a kinematic pin is not a full spherical radius. Larger radii were placed on the pin so as to provide less wear on contact. Vertical side-walls were also included in the kinematic pin layout in the event a carrier requires secondary lateral support. In wear testing, surface finish played a large role where wear occurred; based on this information, E57 requires the surface finish to be less than 0.3mm Ra.

Finally, SEMI E57 describes two sets of three kinematic pins. The 'primary' pins are the default pins to be placed on a loadport. The 'secondary' pins are radially inset from the primary pins. These secondary pins were proposed to allow a carrier hand-off into, or within process equipment or stockers. A plate containing the secondary pins is capable of being lifted through an outer perimeter plate containing the primary pins to transfer a carrier.

Process equipment suppliers need study this standard only if building their own loadports or storage nest within their equipment. The primary to secondary pin hand-off may be useful to some equipment suppliers, especially those designing internal buffers where intra-equipment carrier handling is required.

SEMI E62 Provisional Specification for 300 mm Front-Opening Interface Mechanical Standard (FIMS) provides the shape, size, and mechanical details of the 300mm front-opening SMIF port. This standard specifies items such as the size of the port to which 300mm FOUPs mate, the FOUP registration features on the port, and the latchkeys that unlock the FOUP door from the FOUP. 200mm SMIF ports use one latch mechanism at the center of the port door. After some debate, 300mm SMIF ports were specified to contain two latches allowing the possibility of the wafers to extend into the center of the pod door. Beyond the number of latches, how much latching/unlatching torque the port should produce was well debated. After several rounds of calculations, the task force agreed 1.7-Nm torque (minimum) would provide adequate capability for the sealing needs of 300mm FOUPs.

Two sets of dimensions, one set for 25 wafer capacity ports and another set for 13 wafer capacity ports, are provided within this standard. The 25 wafer capacity port is 120mm taller than the 13 wafer capacity port (additional 12 wafers at 10mm pitch), but the width is the same for both cases.

Process equipment suppliers only need examine this standard if building their own box opener mechanism. Box opener designers are also cautioned to pay close attention to the interaction between FOUP and FIMS. Lead in which may be provided by FIMS registration pins is not desirable, and Box opener makers should work closely with market suppliers of 300mm FOUPs to ensure correct alignment between the two.

SEMI E63 Provisional Mechanical Specification for 300 mm Box Opener/Loader to Tool Standard (BOLTS-M) Interface is possibly the standard that saw the fastest consensus. All loadport suppliers are eager to have a mounting layout on the process equipment, and defined exclusion volumes in which to place mechanisms by which to develop their designs. Although the figure in the standard looks like a box opener unit, this standard is actually specifying the process equipment side of the interface in order to allow box opener interchangeability to a common, well specified interface. This approach allows loadport suppliers some flexibility in their designs and alignment methods.

The box opener is specified as mounting to the process equipment at six possible mounting bolt locations. It should be noted however, that this mounting is not intended to provide the adjustment necessary to align the loadport with the intra-equipment wafer handler. It is intended that the box opener supplier include alignment capabilities within their loadport since the specifications on the BOLTS frame in the equipment is not sufficient for aligning adjacent box openers to a common wafer handling robot.

SEMI E63 is a must for all equipment suppliers who wish potentially to purchase a box opener interface. It provides information as to what volumes must be available at the front of the equipment for the box opener mechanism and the opening of the port door.

SEMI E64 Provisional Mechanical Specification for 300 mm Cart to E15.1 Docking Interface Port is an exclusion volume for a mechanical a docking interface which has been defined and passed by SEMI committee, but not yet assigned a SEMI designation. Due to the 9kg weight of fully loaded 300mm FOUPs, it was quickly determined that operators need some mechanized assistance in transporting and loading carriers. A cart capable of transporting one or more 300mm FOUPs and assisting the operator in loading/unloading it onto a loadport is referred to as a Person Guided Vehicle (PGV).

At the time this standard was developed, no PGV solutions existed on which to base a standard docking interface, however the need for a means to dock a PGV to equipment for assisted loading, while not impacting the equipment itself was soon recognized. At any rate, early in 300mm development IC makers felt the need to specify at least a zone where a mechanical interface would eventually lie. The original assumption was that the supplier of the PGV would provide the docking interfaces for all of the process equipment that would fit within the exclusion volume specified in E64. The docking exclusion space, resembling a 'toe-kick' under kitchen cabinets, was chosen to be at the floor so as to allow the interface to be mounted to the floor (thereby minimizing any shock to the process equipment. The exclusion volume, specified as 100mm high and100mm deep, extends across the full width of the of the process equipment.. After considerable debate, the exclusion volume was chosen across the full width of the equipment to allow rails that extend the full length of a bay, and in case 'guard-rails' are needed to prevent PGV-equipment collisions.

As mentioned earlier, a SEMI Task Force has already successfully defined a standard cart docking interface mechanism that fits within this exclusion volume and is universal so IC manufacturers may use many different brands of PGVs in different areas without custom configurations. This is aimed at reducing design cost for PGV suppliers and install complexity for IC manufacturers.

Process equipment suppliers should review this standard to ensure they have this space available in front of their equipment. There is no requirement to provide a frame or other structure for mounting the cart docking interface; it is specified as being floor mounted. Some IC manufacturers may require equipment covers or shields above this area to minimize the potential for tripping on the cart docking interface.

M31 Shipper Standard is a new standard that was developed out of the need for an 'automatable' shipper. SEMI Japan had developed a 300mm manual opening shipper standard, but some IC manufacturers requested a shipper that can be opened in an automated manner, similar to a FOUP. The SEMI Shipper Task Force spent many hours debating the necessary similarity to the FOUP. Ultimately, this standard defines a carrier that is very much like a FOUP except for its door. It was agreed that an automated FOUP door built for >100,000 cycles would be too expensive for a shipper, and a FOUP-compatible door would only benefit one equipment type in the fab (the wafer start sorter). As a result, this standard only specifies the areas in which 'automatable manual' door latches may exist. The standard also differs from E47.1 in that it allows additional door thickness to better restrain the wafers during shipping.

This standard should be of little or no consequence for most process equipment suppliers unless they are building wafer sorters.

SEMI E72 - Provisional Specification and Guide for 300 mm Equipment Footprint, Height and Weight is a specification aimed at ensuring 300mm process equipment will fit within 300mm fabs. This standard was driven by IC manufacturers to convey their needs and interests. The standard provides a 'cost footprint' calculation which conveys the IC manufacturers request that equipment be deeper rather that wider so as to allow more equipment to be placed in a bay. Deeper is viewed as less costly since typically only one or two equipment in the bay define its required depth. The specification also provides guidance on how much space can be used for auxiliary (possibly sub-fab) equipment and what weight loadings are acceptable.

As this standard defines the architecture of the entire process equipment, it deserves careful attention by process equipment suppliers. Suppliers are also encouraged to actively engage customers in determining move-in size, as it is as yet undefined.

Communication Standards

Process equipment communication interface standards are predominantly wafer size independent. As a result, SEMI Standards E4, E5, E23, E30 and H37 will continue to represent most of the equipment requirements. Each of these standards will be updated and revised per the SEMI 5-year standards review process; minor modifications due to the 300mm closed carrier architecture may be incorporated, but no significant changes are expected to these standards.

300 mm SEMI Standards Compliance Testing

In June of 1997, with many of the needs for SEMI standards identified, industry participants began discussing how to determine if products were, in fact, compliant with the new generation of Standards. With suppliers in need of guidance, and device makers in need of verification methods, I300I invited 3rd party loadport, FOUP, and AMHS suppliers to participate with device makers in the Pod and Loadport Test (PLoT) Development Team. The charter of this team was to devise a comprehensive testing method for determining the level of compliance of FOUPs and loadport equipment to SEMI 300mm physical interfaces and carriers standards as well as applicable I300I guidelines.

Over the next 6 months, and two Semicon events later, the group published through I300I a document known as the Loadport Equipment Class Test Plan. The outline for testing follows:

1. FOUP-loadport Compatibility

2. FOUP Placement/Presence Sensing and Enunciation

3. SEMI E15.1-96 Compliance Testing

   1. Dimensional Testing

   2. Functional Testing

      1. Fixed loadports

      2. Internal Buffer loadports

4. Automation Delivery Easement Verification

   1. OHV

   2. PGV

5. E64 Cart Docking Interface Exclusion Zone

6. SEMI E23 Photo-coupled I/O Interface Location and Functionality

   1. Dimensional Testing

   2. Functional Testing

7. FOUP and loadport FOL/EOL Lockout

8. PWP Testing of FOUP/loadport Combinations

9. Reliability, Availability and Maintainability of loadports

This test plan is the generic test for verifying the load port and box opener (and to some degree FOUP) compliance to SEMI standards and I300I guidelines. This is the first, and currently only, method for validating standards. An important first step in being able to validate standards was the temporary freeze in activity for standards documents. Efforts for a similar testing plan for pods is under development by I300I. Due to the intimate relationship between FOUPs and load ports, it is challenging to separate testing data of the two pieces of equipment. For example, it is not possible to gather only FOUP PWP data and only load port PWP data. Because a FOUP door can not be removed without load port/FIMS equipment, and because wafers can not be cycled on load port equipment without a carrier, the contribution of each individual component is inextricable.

New 300 mm SEMI Standards Presently in Development

While tremendous output in the form of SEMI Standards has been generated, each completed standard seems to lead to the investigation of other related areas. While the earlier discussed standards are nearing completion and are taking form, other standards in progress are briefly described below, with the first two actually passed through technical committee.

E84 Parallel I/O Device : was approved by technical committee during Semicon Japan in December of 1998. This standard specifies requirements for integrating photocouple devices used for overhead hoist vehicle into process equipment. While this standard is young, it will be a critical issue for process equipment suppliers as well as automation suppliers. E23.1 also requires information from the load port, and in the event a 3rd party load port supplier is used, there must be clear communication between all parties involved. This scope of this standard is intended to reign over both interbay and intrabay applications. This is still being clarified through the AMHS Hardware Interbay Interoperability: was passed by technical committee during Semicon Japan in December of 1998. This standard specifies the required clearances in the same spirit as E15.1, except only as it is relevant to the different types of interbay automated delivery schemes. This standard has not yet received a SEMI reference number, but should be published very soon.

BOLTS-C: is an attempt to define communication standards between the load port and process equipment. Because the actual state models of the equipment with load ports are not completely understood by the end user, this activity also, despite much effort, is immature.

BOLTS-E&U: is an attempt to define the electrical and utilities connections and requirements needed to define a common interface for load port integration to process equipment. Much effort has been spent, but this standard is still relatively immature due to a lack of consensus and variety of load port design approaches developed.

EFEM (Equipment Front End Module): began as an all encompassing host view specification of actions occurring on the front end of the equipment. Now mostly refined to an attempt to specify the host view of buffer management.

Carrier ID Readers: is an attempt to specify both the physical and communication requirements needed by equipment to integrate readers into E15.1 load ports. This effort will require a concerted effort between communication experts as well as E15.1 experts for allocating physical exclusions for different brands of readers. Due to fundamental differences between I300I who want rear-of-carrier read capability, and J300 who desire bottom-of-carrier read capability, standards changes are on-hold until some agreement can be reached.

Reticle SMIF Pods: is an attempt to specify the next generation of reticle carriers which, while maintaining the same exterior dimensions and features regardless of reticle sizes, can accommodate either one 6' or one 230mm reticle. This standard is intended to be applicable for transport and storage of reticles in both mask shops as well as wafer factories. The task force has recently completed a ballot proposal for Semicon West '99. The idea for having the same size carrier regardless of the size of the reticle being transported/stored is to avoid automation hardware redesigns when the industry requires 230mm reticles. While there appears to be a minor storage density impact, I300I member companies agree that this is best way to manage the logistics of transporting and storing reticles used in expose equipment from multiple suppliers. This standard is based upon the successful 6' reticle SMIF pod design currently being used in 200mm minienvironment wafer factories.

Proposed 300 mm SEMI Standards Activities

There are two primary topics on the horizon for 300mm standards development: minienvironment integration and standardized FOUP purging.

Minienvironment integration is the most overlooked area of specification and guidance for 300mm. The particle performance of 300mm equipment will depend on their material selection, airflow design and overall implementation of minienvironments. Further complicating this issue is the fact that every equipment model is different. Minienvironment expertise and understanding is 'patchy' within the industry. There are some IC manufacturers and equipment suppliers with extensive experience and others with none.

Gas (nitrogen or clean dry air) purging of carriers is expected to proliferate at 300mm. The 1997 SIA National Technology Roadmap identifies several areas where wafer environment control will be required [ref]. Standardization of purging interfaces has been delayed due to intellectual property issues. Generally, SEMI avoids standardizing areas where known patents exist or may be applied for. SEMI is taking a position to avoid patent issues entirely where possible. The 300mm Physical Interfaces and Carriers Committee has spent considerable time dealing with possible patents pending verses the need to create standards early in the 300mm transition (ahead of process equipment development).

Industry Needs for a Successful 300 mm Transition

While all of the aforementioned standards activities represents a good start to a successful 300mm transition, it is only the beginning of the process. In order to succeed the following must occur:

1. Stability - The 300mm standards developed to date must remain stable. Stability will be the key to credibility. Although it is very tempting to continually update the standards 3-4 times per year as issues arise, a standard which is an unstable moving target will not be embraced by equipment suppliers.

2. Communication - The final decision whether this effort has been successful will be made once process equipment is developed and deployed in IC fabs. It is paramount that equipment suppliers are provided with adequate information and training by which to design their equipment. This training must also occur within the equipment suppliers' sites to ensure that all designers and engineers are familiar with the standards.

3. Consistency - The specification of, and auditing to the standards must be consistent by the purchasers of the process equipment. The consensus and guidance of I300I and J300 drive consistency within the production equipment supplier community.

Conclusions

The last three years have seen unprecedented knowledge sharing, industrial cooperation, and international collaboration for the semiconductor industry. Radical new mechanical innovation and wafer processing strategy prophesied in SEMI Standards are now reality and under the scrutiny of tests developed by the end users developers of this new technology. While the industry is pleased at the success of hitherto theoretical load ports and carriers demonstrating interoperability at supplier sites and at I300I, the most meaningful success is told in the story of global cooperation between IC makers and equipment suppliers. Marketing and product barriers waned in comparison to the language, cultural, and geographical challenges overcome by dedicated SEMI Task Force members who sought to strengthen their own companies by strengthening the industry. 'Interoperability' may be the key word for 300mm physical interface and carrier standards, but it takes on a much broader meaning when applied to those who created them. Whether in Asia, Europe, or North America, dedicated task force members proved that they too, are 'interoperable' being able disagree, discuss, debate, and define standards as a team irrespective of the forum, host location, or language. The 300mm SEMI Standards development process has brought a historically divided industry together and gained the advantage of different experiences and talents.

300mm equipment will continue to prove the vision of standards authors, and will also educate them on the remaining work. Equipment is proving interoperability works in reality as well as theory, but only in concerted efforts. It is paramount that process equipment suppliers be engaged with these standards, as they ultimately own integration of these new elements into their equipment. No more can a single instrument replace an orchestra, than a single piece of automation ensures interoperability. Interoperability relies on a synergy between the process equipment architects, automation interface designers/ 3rd party automation components suppliers, and end users. It is critical for the continued success of 300mm equipment that all elements come together seamlessly through education of area experts in the final configuration of equipment.

Biographies

Stephen Sumner is a Manufacturing Systems Engineer at Intel Corporation based in Chandler, AZ but currently is on assignment in Tokyo, Japan. Stephen concurrently serves in various leadership roles within SEMI from the task force level to the division level helping to guide 300mm standards for interfaces and carriers. His background is in manufacturing simulation modeling, and now works in a corporate group focusing on factory integration of 300mm production and automation equipment. His prior work experiences in Japan combined with his Japanese language skills allow him to balance technical input from both English-speaking and Japanese constituencies within SEMI. Stephen received his BS in Industrial Engineering from North Carolina State University.

William Fosnight, PE is Director of Strategic Technology at Asyst Technologies. He is located in Austin, Texas where he manages Asyst's relationship with SEMATECH, I300I and SEMI. His current responsibilities include the development of 300mm wafer transport, storage and handling products including carriers, equipment interfaces and automation systems. Prior to joining Asyst, he was with Digital Semiconductor, Hudson, Massachusetts where his responsibilities included the development and implementation of contamination control strategies required for advanced microprocessor manufacturing. Prior to joining Digital, he was involved with wafer isolation studies at IBM Burlington, Vermont. He has authored numerous papers and recently contributed to the Defect Reduction and Factory Integration sections of the SIA 1997 National Technology Roadmap for Semiconductors. Fosnight holds BS and MS Degrees in Mechanical Engineering from The Ohio State University and Rensselaer Polytechnic Institute, respectively.

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12/01/2003

SEMI Standard 300 mm Automation: A Case Study

02/09/2010

SEMI Executives Speak Out on Work Visas

02/09/2010

E-Manufacturing Solutions Converge

07/01/2002

Automatically Analyzing Effects of Process Equipment on Yield

08/01/1999

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