Facilities

The Lurie Nanofabrication Facility (LNF) consists of a Class 1000/100/10 research laboratory with approximately 6,000 square feet of work area. The research laboratory consists of five process bays (silicon lithography/diffusion, silicon LPCVD, compound semiconductor devices, thin-film deposition, and dry etching) plus five separate, connected rooms for e-beam lithography and metrology (Class 10) and for compound semiconductor materials growth. A separate Class 10,000 instructional laboratory of approximately 1,000 square feet supports formal courses.

Any process facility considered a clean room requires strict operational and environmental specifications: cleanliness, temperature, humidity, make-up air, scrubber exhaust and waste disposal must all be controlled. Please see below for more information about:

• Clean room classifications
• Humidity and temperature control
• Make-up air and scrubbers
• DI water plant
• Acid waste neutralization system
• Flammable bunker
• Toxic gas bunker
• Fire extinguishers
• Halon fire suppressant system
• Safety shower and eye wash
• Emergency spill center
• Tactical response center
• Life safety system

Humidity and Temperature Control

Since many chemical reactions are sensitive to temperature or humidity changes, temperature and humidity control are a critical part of any clean room. One example of a chemical process that is highly impacted by temperature and humidity changes is lithography. If the temperature or humidity are constantly changing then exposure and development times would also change accordingly. This type of variation is not tolerable in a state-of-the-art clean room. The SSEL humidity specification is 42.5% ± 2.5% and the temperature is 70º ± 2º. If the humidity or temperature goes out of control a set procedure is followed to bring the lab back into conformance. Make-up Air and Scrubbers

The function of a scrubber is to neutralize and in some cases remove volatile process effluents (gasses and vapors) from the air stream. The SSEL has three scrubber units that have a total capacity of 42,000 CFM. To compensate for air exhausted from the clean room through the scrubbers, the SSEL incorporates make up air units. The make-up air in the primary research lab is 38,000CFM. In the case of an emergency (gas release) within the clean room envelope, the clean room will change from positive pressure (0.05" HOH) to negative pressure by shutting the power on the make up air unit. This is to ensure the hazardous volatile process effluents (gasses and vapors) do not propagate to any other part of the building, in particular the escape routes from the laboratory.

Make-up Air and Scrubbers

The function of a scrubber is to neutralize and in some cases remove volatile process effluents (gasses and vapors) from the air stream. The SSEL has three scrubber units that have a total capacity of 42,000 CFM. To compensate for air exhausted from the clean room through the scrubbers, the SSEL incorporates make up air units. The make-up air in the primary research lab is 38,000CFM. In the case of an emergency (gas release) within the clean room envelope, the clean room will change from positive pressure (0.05" HOH) to negative pressure by shutting the power on the make up air unit. This is to ensure the hazardous volatile process effluents (gasses and vapors) do not propagate to any other part of the building, in particular the escape routes from the laboratory.

DI Water Plant

De-Ionized (DI) water is a critical component of the semiconductor process due to the ultra-clean requirements of the device fabrication. The SSEL supplies ultra-high purity de-ionized water throughout the facility. The DI system is capable of making eight gallons/minute with a resistivity of 18-Mohm-cm. There are two 1,500 gallon storage tanks, which provide for short-term demands that exceed the 8-gallon/minute make-up capacity.

Acid Waste Neutralization (AWN)

Reactive chemical effluents, such as, acid and bases are regulated according to federal, state and local regulations. The SSEL incorporates a fully automated system designed to collect and neutralize all acidic and basic waste, to within a Ph range of 8.5 to 9.5 (discharge).

Flammable Bunker

A flammable bunker is a separate and, typically, external structure designed to mitigate the danger which exists when storing flammable and pyrophoric gases. The SSEL flammable bunker has a Class 1 Division 2 classification. This classification indicates in the event of a release the atmosphere in the bunker has the potential to become flammable or explosive. Therefore all electrical enclosures have to be positively purged with an inert gas or sealed to keep hazardous environments away from possible ignition sources. The SSEL flammable bunker sprinkler system is a dry system to eliminate any possibility of freezing. The sprinkler system is pressurized with air. When the air is released, the water will flow. The SSEL flammable bunker roof is also explosion rated, which means in the event of an explosion, the blast will be directed upwards to minimize damage to the building and surrounding area.

Toxic Gas Bunker

The SSEL toxic gas bunker is classified the same as the flammable gas bunker. The only difference between the designs of the two bunkers is the sprinkler system and the roof. The SSEL sprinkler system only releases water into the bunker and not into the actual cabinets. This is to minimize the possibility of generating toxic or corrosive waste by-products from the gas/water reaction in the event of a release. The SSEL toxic gas cabinets are vented to the scrubber system before being exhausted to the outside.

Fire Extinguishers

Throughout SSEL there are strategically placed fire extinguishers. All SSEL staff are trained annually in the proper use of fire extinguishers. CO2 extinguishers are used because they leave no residue after use.

Halon is a very effective fire-fighting agent used for the protection of delicate and highly sensitive electronics. The SSEL has a single global Halon system for the submicron/lithography area (EECS 1450).

Safety Shower and Eye Wash

A safety shower and eye wash are located at end of Special Projects Bay. If there is the possibility of chemical contact there is a safety shower/eye wash station located within 100 feet from any wet processing. Water flow for the shower is sufficient to drench a user rapidly. The shower has a minimum flow rate of 30 gallons/minute. The eyewash provides copious amounts of flow at 0.4 gallons/minute.

Emergency Spill Center (ESC)

Trained SSEL staff members are responsible for all chemical spills larger than a clean room wipe outside of the wet benches. The user's primary responsibility is to alert staff of the name and quantity of the chemical spilled. The SSEL has on site a chemical spill center equipped to handle any chemical used in its laboratories. All major spills would be handled by OSEH with the SSEL staff assisting. The Emergency Spill Center (ESC) is located down the hall from the clean room next to the MSDS cabinet.

The TRC is equipped to handle any release of a hazardous substance that have the potential of impacting the safety or health of occupants of the EECS building. All SSEL staff have been trained as Hazardous Materials Technicians (Level 3 First Responder). The emergency response team has at least one member on-call 24/7/365. The team also conducts weekly and monthly inspections to ensure the equipment is in good working condition. The TRC is equipped with portable gas detectors, SCBA packs, radios to keep in touch with OSEH and DPS and up to Level B PPE. The TRC is located at the west atrium corridor. If a gas leak occurs after hours the on-call person is notified and can check the intranet from any remote area to determine the level of response and notify appropriate personnel (SSEL Staff, DPS, AAFD, and OSEH).

Life Safety System (LSS)

The SSEL has a life safety system that monitors for gas, as well as other hazards, throughout the laboratory. This system provides state-of-the-art monitoring thereby providing the highest level of protection for the laboratory, surrounding environment, and personnel occupying these areas. There are two distinctive types of gas detection systems used at the SSEL. This hybrid approach provides for improved emergency response, local observation of gas levels, remote sensing and optimized sensitivity.

Satellite:
This is the first type of detection used. It utilizes an electrochemical cell for detection. It monitors resistivity changes in electrolyte due to the presence of a specific gas. The satellites also include a local error detection algorithm that minimizes false alarms. The satellites are located in the labs, around the outside of the lab and at the TRC. The various posted locations are to ensure the safety of all people in the building.

Zellweger Analytics/MDA:
This detection system is commonly referred to as a System 16 and draws a sample of air across a chemically sensitive tape. The air sample is pumped from the detection point to the detection head through plastic tubing that can be up to 150 feet in length. If there is detection the tape will stain and an alarm will be generated.