Lab Members Meeting Notes
A Microlab Lab Member Meeting was held on Thursday May 3. We had an excellent turnout; 20 Members attended – 1 faculty, 5 staff, and 14 researchers. These notes summarize items discussed, lab member requests and follow-up actions.
Safety
Access Abuse: Multiple members report access abuse (not logged in) especially during evenings and weekends. Several software modifications to control abuse were discussed. Management will evaluate. Members are reminded that being in the lab without being logged in is an egregious violation of Microlab safety policy and may result in lab access being denied. Assured 24/7 access for the new lab is presently under discussion. This privilege is dependent upon our exceptional safety record and constructive self-policing culture. Members are encouraged to maintain that tradition and insure our full time lab access in the future.
Facilities
Card-Key Access Issues: The Cory Hall card-keys are under the
control and jurisdiction of the UC Police Department. Over the Spring Break,
the UCPD decided to upgrade the software. It was discovered that the software
upgrade was incompatible with some older control boards resulting in card keys
not working. Most of this issue has been resolved as of this update. Lab
members who continue to experience card key problems should report these to
Cory Hall Room 145: The floor of 145 Cory was tiled to accommodate the laboratory of Prof. Clark Nguyen. 145 will be a shared space between Prof. Nguyen and the Microlab until the completion of the Marvell Lab.
Equipment and Process
centura: Two additional chambers have been donated for the Centura by Applied Materials. These chambers have been set in place and installation is underway. Startup at the beginning of Fall 2007 semester is anticipated. Regular status updates will be sent to members as the install nears completion.
edwardseb3: Gun focus, beam scanning, pumpdown time and base pressure issues.
1) Gun Focus Issues: e-gun has been cleaned and rebuilt since May 3 meeting. Member reports significant improvement in evaporation rate. e-gun review and cleaning has been added to the maintenance calendar at 1x/6week intervals. We will also clean the gun when focus or dep. rates are lost.
2) Vacuum Issues: edwardseb3 was part of an equipment donation. It was immediately modified from diffusion pumping to turbomolecular pumping for a cleaner vacuum. The current 340 slpm turbopump plus the gas load of the chamber determine the pumpdown time and ultimate system base (equilibrium) pressure. Microlab will make the following upgrades to the edwardseb3 vacuum system:
· increase the pumping speed by installing a cryopump in lieu of the turbo. This will 10X the pumping speed for N2.
· remove the impedance of the cold-trap by removing the trap (the original purpose for the cold trap was to prevent the back-streaming of diffusion pump oil. Currently, the cold trap serves as a water-vapor pump or Meisner-trap).
· modify the wiring used for the heat lamp to remove insulation (virtual leak).
· implement the heat lamp for the pumpdown cycle.
· We will aim to accomplish these upgrades with minimal downtime.
flexus: What is the status of a flatscreen for the area?
flatscreen monitor ordered following the meeting.
gcaws2: AWH issues are significant; wafer throughput has become unacceptable.
Problems with the expose button and wafer handler issues are probably the result of the computer receiveing interrupts (noise) from some as-yet-to-be-determined source. Equipment engineer is aware of the additional symptoms described at the lab members meeting. Until issues are resolved, using the manual load feature is recommended as an alternative to the AWH. The equipment header will be modified to provide guidance on manual loading. At this point, we believe an intermittent cable or connections at the backplane may be the cause. We are working with our service vendor to remedy this issue.
leo: The cleanliness of the work area will be monitored for abuse. A small screwdriver will be mounted to a ball chain to keep it from getting lost. Recharge of reservation abuse may be implemented. Lab members are again requested to respect the reservation policy. Modifications to the sample holders to assure the sample lays flat on the multi-sample holder are being reviewed. Lab member input on the sample holder design is welcomed – email evan@silicon.eecs.
Mask Cleaning: A chapter has been added to the lab manual providing guidance for mask cleaning (4.33) Lab members are reminded that no mask cleaning is to be performed at the Sink6 or Sink8 piranha baths.
n2 guns: Too weak
All N2 guns will be inspected and pressure increased where appropriate.
oxford2: Provide notice of maintenance.
Microlab staff will be diligent in reserving the oxford2 for maintenance. We are working with an outside service vendor to repair and calibrate the rf-match. Once this is done, a lower power RF supply will be installed to assure RF power control at low wattage settings.
ptherm: Wafer/die holder plates will be made to accommodate lab member needs such as holding slides and chips. A model plate is being fabricated to test and for lab member feedback.
sink432c: Ergonomics and exhaust issues
In response to lab member input the following modifications have been initiated: check exhaust, reconfigure sink location, add on/off water button, relocate deck hoses, install soft curtains in lieu of hard plastic at ends of sink face.
srd’s: Door sometime does not seal causing an error code.
The door bladders for Vertec srd’s are now made slightly larger. It requires more force to assure the door is fully closed before starting the cycle. If the door is not fully seated an error code appears. To facilitate correcting this error we have added vent buttons to allow lab members to vent the bladder and reseat the door.
spinner1: Improve exhaust - remediate lid insert issue.
The fume exhaust to spinner1 has been increased. The effect of improving this utility is not realized when the lid is not in place or inserts are not used as needed. We will look into modifying the lid to facilitate maintaining the correct “open area” when spinning wafers.
solvent squirt bottles: Members question the utility of vent holes in solvent squirt bottles. Lab staff intentionally places these holes in solvent bottles to prevent leakage upon grasping a full bottle and minimize siphoning after fill with cold solvent. This technique is common in many chemistry labs and simply requires placing your index finger over the hole when dispensing. Lab staff will make these holes smaller to make this modification more convenient.
technics-c: A modified technics-c has been installed allowing 6” and 8” wafer placement. A summertime high school intern will be given the task of characterizing etching rates and uniformity for the new geometry.
RH, BF
10 May 2007