450mm Standards Update: June 2014
By Kevin Nguyen, SEMI
While the timing of a transition to 450mm wafers remains unclear, the industry is continuing to develop the standards that will be essential to high-volume manufacturing on larger substrates. The first standard proposal was submitted in 2007, and SEMI has since published nearly twenty 450mm-related Standards. New standards are being developed as the industry identifies new requirements, and revisions to published standards are being made as areas for improvement are recognized.
The International Advanced Wafer Geometry Task Force issued ballot 5654 in cycle 2-14, revision to SEMI M49-0613, Guide for Specifying Geometry Measurement Systems for Silicon Wafers for the 130 nm to 16 nm Technology Generations. The purpose is to reduce 450mm wafer edge exclusion from 2 mm to 1.5 mm for 16 nm technology generation. This ballot will be adjudicated at the SEMI North America Silicon Wafer TC Chapter meeting in July 8, 2014 during SEMICON West in San Francisco, California.
While doc. 5654 is aiming to revise measurement system standard, doc. 5655 is attempting to increase the Fixed Quality Area (FQA) from 223 mm to 223.5 mm for 450mm polished wafer in SEMI M1-0414 – Specification for Polished Single Crystal Silicon Wafers. These changes are significant since there may be limitations in verifying the quality of wafers close to the wafer edge due to limitations of measurement equipment.
Another highly anticipated Standards activity (doc. 5604) on 450mm notchless wafer is taking center stage for the Silicon Wafer materials. The International Polished Wafer and International 450mm Wafer Task Forces proposed adding a 450mm notchless wafer specification in SEMI M1-0414. Driven by the G450C, the proposed changes will improve the wafer symmetry and increase the utilization of wafer surface. However, eliminating the notch will require replacement with several fiducial marks scribed on the back of the wafer’s surface.
Ballot 5604 is currently being issued in cycle 4-14, and the deadline for voting is June 23, 2014. This ballot will also be adjudicated at the SEMI North America Silicon Wafer TC Chapter meeting on July 8, 2014 during SEMICON West in San Francisco, California.
The Japan Assembly & Packaging Technical Committee (TC) Chapter initiated document 5636 in effort to meet the demand of Automated Material Handling System (AMHS) manufacturers by adding detection area in Tape Frame Release Bar (TFRB) by revising SEMI G92-1113 Specification for Tape Frame Cassette for 450mm Wafer. The document was approved by the Japan Packaging TC Chapter at the March 20, 2014 meeting. The new version of G92 will be published after procedural review is completed.
The 450mm International Physical Interface Carriers and International Process Module Physical Interface Joint Task Forces proposed revisions (doc. 5626) to both:
- SEMI E154-0713 – Mechanical Interface Specification for 450mm Load Port, and
- SEMI E166-0513 – Specification for 450mm Cluster Module Interface: Mechanical Interface and Transport Standard
The intent is to improve Equipment Front End Module (EFEM) pocket volume allowing conventional robot to have extra range of vertical motion. This document was approved by the Japan Physical Interfaces & Carriers TC Chapter during the April 14, 2014 meeting, and is now undergoing procedural review. While SEMI has a 300mm wafer shipping system standard (M45), a specification for the 450mm generation has not been standardized. The International 450mm Shipping Box Task Force is making a second attempt to gain consensus for doc. 5069A, Specification for 450mm Wafer Shipping System. The first ballot failed to achieve consensus at the SEMI North America Physical Interfaces & Carriers TC Chapter during the April 2, 2014 meeting at Intel in Santa Clara, California. The Task Force is now reviewing feedback from the first ballot that will be incorporated into the subsequent ballot.
If your company is not yet involved in these efforts to shape the future, learn more about SEMI Standards by visiting www.semi.org/en/Standards. Note that participation in the SEMI Standards Program is free, but requires registration. To learn more, contact your local SEMI Standards staff or register at: www.semi.org/standardsmembership.
For additional 450 information (PPTs, viewpoints, etc.), visit 450 Central at www.semi.org/450.
SEMI, Standards Watch - June 2014