The Wisconsin Center for Applied Microelectronics (WCAM) at the University of Wisconsin-Madison provides a research facility for microfabrication technologies, products and innovations. In order to give students a state-of-the-art education and to maintain leading-edge research programs, we continue to improve this advanced laboratory.
- How much does it cost to use WCAM?
WCAM is a cost recovery facility, which means our operating expenses are partly supported by charges to users. Each year, the WCAM Advisory Committee reviews the user fee schedule and sets recharge rates. WCAM rates are generally at or below the median for similar University research labs in the U.S.
Access to some tools in the lab is included in each user's monthly lab access charge, with no additional fee. Many tools carry a cost, billed to the user's account at an hourly rate; different tools have different rates, depending on their cost of operation. In a few cases there may be additional fees for the use of very expensive materials, such precious metals in deposition tools. See the user fee schedule for current rates.
- How can I obtain access to WCAM?
Full details of the application process, including links to all the resources you need, can be found in the
Getting Started
section of this Web site. In summary, to become a user of the WCAM cleanroom, you must:
- Read, understand, and agree to abide by WCAM's safety rules
- Sucessfully complete WCAM's online Lab Safety and Orientation Course
- File a User Information form, including documentation of a valid funding source
- Come to the WCAM labs for an on-site orientation session
- Have a specific project or work to perform at WCAM, and a plan for beginning your work.
(Why?) WCAM staff are happy to discuss your project with you.
- As part of maintaining your access to WCAM, you will be required to attend annual renewal sessions.
- Why do I need to know what I want to do in the lab, before I can get access?
WCAM frequently receives requests from new users who don't have a specific project to work on or task to accomplish, but who ask to "learn the cleanroom", or who submit a long list of equipment and ask to be trained on all of it at once. Generally, we find that it is unproductive to train a user on a tool unless he has a current need for that tool. There are several reasons for this:
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Users who train on a tool that has no connection to some project that is important to them, don't learn to use the tool very well. But when completion of your thesis depends upon successful use of a tool, the quality of of your learning experience sharpens considerably.
- If a user learns a dozen tools all at once, some of them are likely to turn out to be tools he never needs to use. Training in this case is an unproductive use of both the user's time, and the time of the WCAM staff member who does the training. Worse, it ties up a tool so that it can't be used by someone who actually needs it for real work.
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Unpracticed skills deteriorate quickly. So, even if a user who is trained on a tool he doesn't need right away does eventually need it later, he usually needs to be re-trained (which wastes everyone's time) or he is an underskilled user of the tool (which is bad for everyone in the lab).
Everything that applies to individual tools applies to the lab as a whole: it is unproductive to bring a new user into the lab, until he has some reason to be in the lab. Therefore, you must demonstrate that you have actual work to do at WCAM, before you are granted lab access; and you must show that you have actual work to do on a tool, before you may receive training on it.
- Which supplies and materials does WCAM provide?
The following are provided as part of your access fee, for use in the WCAM labs only:
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Protective garments: Full cleanroom suits; cleanroom gloves; safety glasses; face shields and chemical aprons; chemical gloves
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Supplies: Cleanroom wipes; swabs; photoresist pipettes; photoresist bottles
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Chemicals: Permitted solvents; process chemicals for wet chemistry and thermal processing equipment
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Deposition materials: Sputtering and evaporation sources for metal and dieltric deposition systems. See the current list of available materials for details. Use of precious metals may influence the cost of using deposition tools.
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Photolithography materials: WCAM supplies reasonable amounts of several popular photoresists and their developers, as part of your access fee. See the current list of available materials.
- What should I bring with me to the lab?
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UW ID card: Required for access to the cleanroom
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CRESS project name and password: You must know these in order to enter the lab equipment area, and to use equipment
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Samples: Bring your cleanroom-comopatible samples that are ready for work on your project
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Process information: You should know what you need to do, and how to do it, before you sign in to the lab. Consult with other members of your group, or with WCAM staff, for advice and information about how to accomplish the work you need to do for your project.
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Materials specific to your project: Examples include photomasks, glassware, and approved chemicals not supplied by WCAM
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A way to record your work: Notebooks must be cleanroom-compatible (NOT paper). Wireless network access is available in the lab, so netbooks or laptops may be used.
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A way to manipulate your samples: Whole or partial semiconductor wafers are best handled with wafer tweezers, not with normal pointy tweezers
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A digital timer: Needed for timing many processes
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Sample storage: Pucks or boats for wafers are handy. Many users buy a plastic fishing-tackle box or something similar, so they have clean storage for all the stuff they must carry back and forth between WCAM and their own labs.
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Clean, closed-toe, flat-heeled shoes: There are shoe cleaners outside the lab entrance, but they are meant for removing only small amounts of loose dust and dirt. Do not use them on shoes or boots that are wet, muddy, or snowy. Many users keep a pair of clean shoes in their office, to wear at WCAM. For safety, your shoes must enclose your foot; sandals, flip-flops, etc. are not OK. High heels don't work in the cleanroom boots, so don't even try.
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Comfortable clothes: Before entering the lab, you will put on a complete cleanroom suit, including a hood, coverall, and boots. You may it impracticle to wear bulky clothing under the suit. The suits do not breathe, so some users find it too hot to wear heavy shirts. The suits have two legs, so you may find it more convenient to wear pants or slacks, rather than a skirt or dress. Outerwear, such as coats or jackets, is not allowed in the lab. You may leave your coats, backpacks, sweatshirts, etc., at your own risk, in the lockers provided by WCAM outside the lab.
- What must I not bring with me to the lab?
Because the WCAM labs are a controlled environment in which we seek to minimize particles and contaminants, there are many things you must NOT bring into the lab. These will be discussed more fully at your on-site orientation session. Prohibited items include, but are not limited to:
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Food and drink: Well, duh!
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Coats, jackets, backpacks, purses, etc.: Anything that is not made of an approved material and has been exposed to the outside air is prohibited. You may leave these items, at your own risk, in the lockers provided by WCAM outside the lab.
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Particle sources: Paper, cardboard, wood, etc. are prohibited. No fabric other than your cleanroom suit may be exposed in the lab. No skin may be exposed, except the area exposed by the cleanroom hoods, and your hands during required glove changes.
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Items that have been exposed to a non-cleanroom environment: Everything entering the lab must be wiped down and passed through the air shower in the WCAM gowning room
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Chemicals not approved for use in at least one tool: Unless a material has been approved for use in some specific tool in the lab, it may not be brought into the lab at all
- Where can I buy the stuff I need?
If you need wafer tweezers, cleanroom notebooks, epi wafers, an optical mask, etc., you can check this
list of suppliers for suggested sources. Of course, WCAM does not guarantee or endorse any of these companies; they are just places that we know people sometimes buy things from.
UW departments and groups can buy many cleanroom supplies and other useful things online, through the UW's
Materials Distribution Services (MDS) system. If your group has an account, MDS gives you access to Fisher Scientific, VWR, Sigma-ALdrich, and Grainger. Items purchased through MDS may be eligible for academic discounts.
- Can I come into the lab as a non-paying observer?
No. Everyone in the cleanrooms is a lab user: this helps ensure that everyone in the cleanroom shares an interest in helping maintain a productive, contamination-free environment. Everyone using the cleanrooms must sign in through CRESS, and CRESS accounts must be connected to verified funding sources.
- How long will it take for me to obtain access and get to work?
- If you already have a University of Wisconsin NetID, WCAM staff can usually enroll you in the online course within one business day of receiveing your request. Most applicants finish the course in three hours or less.
- After receiving your completed User Information Form (including your PI's signature and funding information), WCAM staff can usually create your account within one or two business days.
- After establishing detailed information about what you want to do at WCAM, and which equipment or processes you need to use first, WCAM staff can usually schedule your on-site orientation within one or two days. The orientation takes 20 - 30 minutes, and may be followed by your initial equipment training session.
See also
Why do I need to know what I want to do in the lab, before I can get access?. Users can avoid delay at this step, by having a clear idea of what they want to accomplish in the cleanroom. WCAM staff are happy to discuss your work with you, and to help you decide which tools you need.
- The time required for training sessions varies with the tool being taught; discuss this with the WCAM staff member responsible for the tool you want. (See the
Equipment section of this Web site for a list of tools and the staff associated with them.)
Many tools at WCAM require at least a three-step training schedule: First, staff and user meet, and the staff member trains the user. Then, the user comes in to use the tool alone, during regular working hours, for one or more practice sessions. Finally, the user schedules a demonstration session with the staff member, during which he must display proficiency with the tool. Sometimes users fail, and require more training and practice. After a successful demo session, the user may be granted access to the tool.
- What is CRESS, and what does it do?
CRESS stands for Clean Room Equipment Security System. It is an access control system for WCAM tools and lab space. The CRESS
shows who is in the lab and which equipment is currently in use.
From the point of view of lab users, CRESS serves three central functions:
- CRESS records usage of the laboratory and of each piece of equipment by each user, and handles billing
- CRESS provides equipment training management, so that only qualified users may log on to tools. (For a description of why this is good for everybody, see
Why can't my friend train me on the tools?). To be granted CRESS access to a piece of equipment, a user must be trained by a staff member, demonstrate mastery of good operating practice, and continue to operate the equipment without violating any lab safety or contamination rules.
- CRESS controls tool interlocks, so that some function of a tool is disabled unless someone has checked it out in CRESS. This keeps unauthorized people from using the tool.
Understanding the details of the CRESS interlock on a given tool may be an important part of your training. For example, some of the plasma etch tools generate an alarm when CRESS disables their process gas manifold valves. You need to know that this one particular alarm may be safely silenced and ignored on these particular tools, while other alarms carry important information to which you are required to respond.
- Will I receive equipment training from WCAM staff
Yes. WCAM staff conduct training on all tools and processes in the lab, by prior appointment. You can find out which staff member is responsible for which tool by checking the
Equipment section of our Web site. The training may also include tips on accompanying processes. After training and practice, each person demonstrates knowledge of operating procedures in order to receive access the equipment. Some pieces of equipment require more than one training session. No one may use equipment unless he has been trained by WCAM staff, and given access in CRESS.
- Why do I need to have actual work to do on a tool before I can receive training on it?
See the answer under
Why do I need to know what I want to do in the lab, before I can get access?
- Why can't my friends train me on the equipment?
Hundreds of users from dozens of research groups rely upon our equipment to be in good working order whenever they need to use it. It is important to everyone's research that each time they use a tool, the results are as nearly as possible the same as the last time they used that tool with the same parameters. To maintain reliability, every user must be thoroughly and uniformly trained on each piece of equipment they need to use.
When users train each other, important information may be lost or distorted in successive generations. For this reason, all training at WCAM is done by staff members.
- Why don't you have superusers who can do training?
Because we don't need them. In most cases, WCAM staff can schedule a user's training on a tool within several days of receiving the request. Users can avoid delay by planning ahead.
