Methods and apparatus for positive wafer process status...

Material or article handling – Apparatus for charging a load holding or supporting element... – Condition responsive control of transporting means

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C414S940000, C414S787000

Reexamination Certificate

active

06530734

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to methods and apparatus for semiconductor wafer processing and manufacture of micro-circuit devices, and more particularly to methods and apparatus for positively identifying the processing status of a plurality of semiconductor wafers that are being processed using multi-wafer cassettes as a transport method.
2. Background and Description of Related Art
As is well known, in semiconductor wafer processing, a semiconductor wafer is treated in a number of processing steps to form a plurality of micro-circuit devices on the wafer. Typically, such processing includes successive steps of chemically treating the semiconductor wafer, applying a photosensitive coating to the substrate surface, imaging a circuit pattern onto the substrate coating at a plurality of locations on the substrate using lithography equipment or the like, treating the exposed coating and then repeating the foregoing steps to build up the micro-circuit devices. Such processing treatment further includes, for example, solder printing processing to form electrical connections on the respective micro-circuit devices formed on the substrate. In order to produce micro-circuit devices in volume, large scale production facilities process hundreds of wafers during such processing. Conventional semiconductor wafer processing systems electronically track the process status with computer system controllers and displays that provide the operator with limited status messages, for example, cassette A, wafer no. 15. However, in the event of a power outage, emergency power-off or system malfunction, the process status information may be lost or corrupted, so that when restarting the system, it is not readily possible to determine the processing state of the various wafers in a cassette, or full cassettes of wafers.
SUMMARY OF THE INVENTION
The methods and apparatus of the present invention overcome the problems of the prior art and improve the manufacture of micro-circuit devices by providing positive wafer process status identification during semiconductor wafer processing in which a robotic arm moves wafers between a storage cassette located on a cassette holding station and a wafer processing station. The system comprises a mechanical indicator flag movable between at least two, and preferably at least three, processing state indicating positions; and an actuator member connected to the indicator flag and actuated by movement of the robot arm to move the indicator flag. The robot is controlled to move the indicator flag to different processing state indicating positions via the actuator member during the processing according to the stage of the processing and the sensed position of the indicator flag.
The wafer process status identification system of the present invention provides a positive, i.e., fool-proof, indication of the processing state of each wafer cassette during the semiconductor wafer processing that allows an operator to immediately determine which cassette or cassettes are finished, which are partially processed and which are awaiting processing. Costs attributed to system status uncertainty during error recovery are reduced, and production efficiency is improved. These and other features and advantages of the invention are described in or are apparent from the following detailed description of the preferred embodiments.


REFERENCES:
patent: 4498668 (1985-02-01), Bowen
patent: 4926786 (1990-05-01), White
patent: 5388945 (1995-02-01), Garric et al.
patent: 5778818 (1998-07-01), Marshall
patent: 5884392 (1999-03-01), Lafond
patent: 6014942 (2000-01-01), Perka et al.
patent: 6018688 (2000-01-01), Hashimoto
patent: 6050214 (2000-04-01), OKeefe
patent: 6142722 (2000-11-01), Genov et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Methods and apparatus for positive wafer process status... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Methods and apparatus for positive wafer process status..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods and apparatus for positive wafer process status... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3008887

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.