MEMORANDUM
To: Katalin
Voros, Operations Manager
From: Marilyn
Kushner, Junior Development Engineer
Cc: Sia
Parsa, Process Supervisor
Subject: 2008 Year-End
Report
Date: 15
January 2008
The
photolithography equipment used in processing that are under my direct
involvement are: the GCA Wafer Stepper(2), the GCA Wafer Stepper(6) the GCA
Pattern Generator, the Ultratech Mask
Copier and the ASML. Additional equipment in this group includes the APT chrome
and emulsion mask developers, and the 4” and 6” tracks for coating and
developing wafers.
The
online mask-making form for mask-making requests is utilized by all lab members
submitting a mask request, as well as other university affiliated researchers
and BMLA lab members.
Mask-making
requests are accepted for both the GCA Wafer Steppers (gcaws2 and gcaws6), the
Quintel contact printer, the Karl Suss contact aligner, and the Canon 4:1
reduction printer. Requests are also accepted for the advanced lithography ASML
stepper.
The
pattern generator continues to be utilized on a daily basis by myself and the
selected group of lab members who are carefully trained and then qualified to
operate it. A total of 756 completed photomasks were logged into the gcapg log
book by the end of the calendar year, December 31st.
Note: The drop in the Mask total
from last year (930) again was largely caused by out-sourcing to Photo
Sciences, Inc. and Toppan Photomasks; the latter is contracted to make
photomasks for the CMOS baseline process as mask geometries less than two
microns are below our machine capability and/or resolution. There is, however, a silver lining to this: I
was able to execute speedy mask-making turnaround times on a consistent basis-
frequently same-day service.
Former
Microlab lab members who are now faculty within the UC system And beyond
continue to be tremendously loyal and supportive of the Microlab’s mask-making
facilities and refer our services to research groups within their own university
systems; this group continues to grow as many former lab members are now
faculty elsewhere throughout the United States and continue to support the
mask-making facilities in the Microlab.
New for 2008:
|
University |
Contact |
Department |
|
Caltech |
Alexander Champagne |
|
|
|
Yanfei Yang |
|
|
|
Kelvin Liu |
|
|
|
Xiaole Mao |
|
|
|
Daniel Woodsworth |
|
|
UC |
David Yang |
|
|
UC |
L. K. Shen |
|
|
UC |
Xi Wang |
|
|
|
Ben Cooper & Adrian Southard |
|
|
|
Nikolas Chronis |
|
|
|
Richard Everly & Robert Tufts |
|
|
|
Anastassios
Mavrokefalos |
|
|
|
Dongyan Xu |
Physics & Astronomy Mechanical Engineering |
Ongoing:
|
University |
Contact |
Department |
|
Caltech |
Blake Axelrod |
Condensed Matter
Physics |
|
|
Professor Paola Barbara |
Physics and
Pharmacology |
|
|
Professor Shaorong Liu |
Physics and
Biochemistry |
|
N/A |
Center for Superconductivity Mechanical Engineering/Institute for Systems
Research Nanoelectronics Research Group |
|
|
Professor Li Shi & students |
Mechanical Engineering |
The
GCA Pattern Generator as scheduled monthly maintenance tasks that are performed
on a routine basis. They are: the mercury lamp change every 700 hours (followed
by focus/exposure tests for chrome and iron oxide after the lamp has burned in
for 24 hrs.) Emulsion focus/exposure tests are done on a as needed basis. Other tests for the
pattern generator are the angles and alignment test, which is performed monthly
on both chrome and emulsion plates, and the stage motion tolerance test which
compares two different tolerances. By strictly adhering to a six-month major
maintenance call to RZ Associates for stage maintenance, machine uptime for this tool continues to be
superb.
GCA Wafer Stepper (gcaws2)
The GCA Wafer Stepper has a scheduled mercury arc
lamp change every 900 hours; this is performed by Evan Stateler, the engineer-in-charge
for this equipment. After a 24-hr. lamp burn-in, new focus and exposure tests
are performed to determine the best focus and exposure times for both I-line
and G-line resists. A clear energy test follows, then a baseline correction.
The baseline correction test is also performed once and week and on request.
GCA Wafer Stepper 6-inch tool (gcaws6)
For this 6”
tool, I am sharing the preventive maintenance with Kim Chan. A weekly baseline
test is performed, as well as the micro-dfas baseline test.
ASML Stepper (asml)
IQC tests and illumination
uniformity are performed three times a week, essentially after the laser
refill.
The lamp
intensity is measured at five points on a weekly basis using the Karl Suss UV
Intensity Meter. Measurements are taken for both I-line and G-line and recorded
in a logbook kept by the tool and then posted online.
Keeping
the Microlab picked up and presentable is still a challenge- even though it is
stressed during the etiquette portion of lab orientation that a cleaned-up work area makes lab life more
pleasant for all.
Therefore,
the annual Microlab CleanFest held in late October is essential. This year approximately
100+ active lab members signed up and once again their efforts- appreciated by
all- made a tremendous difference in the lab’s overall appearance and boosted
morale. Just like last year, many of this year’s participants were new
labmembers who had just started to use the Microlab, but they came in to clean
with a great generosity of spirit that made my task of organizing this event
much more gratifying.
The daily grab-bag giveaway continues to be popular; prizes
were gathered from the Semicon West Show at the
Prize-filled tote
bags were also given to the first lab member to sign up for this event, as well
as the most cheerful, willing participant.
Photolithography:
For the Mathies Lab: Characterized thin (.070 mils) borofloat 5”
photomasks which were specially ordered by this group for their research
projects.
And
for one of our major BMLA contributors:
worked on a one-to-one basis with their engineer
On
the GCAWS-6. This involved training the
person on all the photolithography equipment from preparing their wafers for
exposure (HMDS oven), coating the wafers
on the 6” coating track, exposing the wafers on the gcaws6, then developing the
wafers on the 6” developer track and lastly
inspecting them on the uvscope. Before the end of the year this person was able
to work
Independently
on these tools, but I remained on call for assistance.
The
Microlab goes green: a vendor was
located to buy our silicon scrap wafers, both whole and
In
pieces, to be reclaimed. The first
shipment of 31 pounds netted the Microlab $$$; and now there are special
silicon wafer collection containers is most of the rooms in the Microlab to
gather up the wafers for future shipments. Lab members are being extremely
cooperative in this issue.
The
Good News photo display case located midway down the main hallway
outside the Microlab is also maintained by me; it’s a revolving display of life
inside the Microlab.
This year I again chaired the barbecue committee in general and was aided by
several co-chairs: Madeleine Leullier for the publicity poster; Joe Donnelly
for all-around assistance, and other staff members stepped up to volunteer for
the
Picnic site setup, the grilling, the organized
sports, and the final cleanup.
And once again, our Microlab Operations Manager,
Katalin Voros, generously sponsored this picnic at her local neighborhood Orinda
Oaks Park. Fifty staff and lab members attended and a good time was had by
all once more- although a little subdued due to the overlying haze from the big
forest fires in neighboring counties.
Ongoing:
I am working closely with our new baseline engineer, Laszlo Szabo, to handle GDS
mask files from other universities which needed to be converted into tap and
tix files.
The
student staff position that was created
to keep the coffee room, Microlab lobby and the Microlab in general looking presentable continues to work out
well; this student employee, under my general supervision, works with a high
level of independence and manages this job quite well; tasks are added as the
need arises. I also supervise the
student staff that stocks chemicals and lab supplies for the Microlab and
packages up chemical waste for pickup by EH&S.
The major photolithography equipment (the GCA Wafer
Stepper and the GCA Pattern Generator) continue to be among the most heavily
used pieces of equipment in the Microlab. For both pieces of this equipment lab
members tend to train each other, but I continue to grade the written tests and
conduct the oral exams.
Following the Microlab Orientation course and lab tour, each new lab
member is required to take the Microlab Orientation Safety Test. The questions
from this test are from the orientation, safety video, lab tour and study
handouts. This year the test was
significantly revised/updated.
Lab Member Committee Meetings
There was
only one meeting this year, held on January 24, 2008, that was well attended: 20+ Microlab labmembers
and a fair sampling of Microlab staff.
The Microlab suggestion box (located in the main Microlab
hallway) is checked periodically for new safety suggestions submitted by lab
members. The items brought up are discussed with the Microlab manager. To date,
the submissions continue to be excellent and I work with our safety manager to
implement them as soon as possible; the suggestions and improvements are posted
online for reference.
Online
equipment manuals need to be revised and/or updated periodically to reflect
changes in processing and/or procedures as well as to integrate suggestions and
ideas from labmembers. The following chapters have been updated or revised this
year:
April 2008 - Chapter 4.32
- General Resist Parameters
Minor
editing corrections for consistency. Updated the post exposure bake column
August 2008 - Chapter 2.5
- Sink5
Added references to the pre-furnace clean metal bath in
sections 3.0, 6.0, 8.0, and 9.1
Deleted
any remaining references to the obsolete HMDS setup at this sink
Revamped section 9.5
to describe the gravity drain spigot system for the PRS-3000 photoresist
stripper
Deleted figure 4 (the HMDS timer)
October 2008 - Chapter
2.6 - Sink6
Expanded
the section on sink6 protocols, Section 8.3 to integrate my own suggestions and
well as the excellent ones from the device group
Removed
the reference to the old-style sink6 from Section 9.0 (sink operation)
Miscellaneous: Redesigned
the data sheets for the gcaws2 baseline correction, the gcaws6 microdfas
baseline, and the pattern generator focus/exposure tests
Also provided input to
our temporary hire, Endré Szentkiralyi, who totally revamped the Microlab
Orientation Safety Test to make it more user-friendly, but still covering all
major points of safety within the Microlab. This streamlined test revision
enables me to grade the tests much more quickly and get the new lab members off
to a quick start.