Equipment Engineering at Nano3

Nano3 - a microfabrication cleanroom facility located at the University of California, San Diego - provides nanofabrication equipment access to researchers and industry in the Southern California region. It's also an arm of the Qualcomm Institute - a research department at UCSD aimed at cutting edge innovation and emerging technologies.

As an equipment engineer, my responsibilities included the maintenance, repair, calibration and upkeep of a significant portion of this equipment, including thin film deposition, plasma etching, and facility support equipment. While my primary responsibilities revolved around troubleshooting, my responsibilities also regularly included large-scale equipment upgrades, installations, and preventative maintenance, as well as the design and implementation of novel solutions to unique user requests.

Qualcomm Institute

Nano3

Troubleshooting

Troubleshooting of nanofabrication equipment is dependent on a comprehensive understanding of many interrelated systems and components. A single machine may have multiple generators, a complex high vacuum system, wafer transfer systems, coolant delivery systems, and toxic gas delivery systems.

Each individual sub system has its own points of failure, such as the dozens of seals in the high vacuum system, or the valves in the gas delivery system, and small changes in one system can have drastic effects on others, both up and downstream of the problem source.

Above: Implementing repairs on the lower electrode of an Oxford Plasmalab 100 RIE Etcher

The lower end of the Oxford Plasmalab 100 RIE Etcher

To troubleshoot effectively, it is necessary to work backwards from a failure state or observed problem and identify all possible causes of that particular outcome, then develop ways to test and identify the failure and finally develop a solution, whether that be a small setup adjustment or the total replacement of a failing component.

A good framework for troubleshooting can make the difference between long periods of equipment downtime and user experience issues, and a healthy preventative maintenace schedule that anticipates many possible failure cases.

Temescal Airco Electron Beam Evaporator Upgrades

The Electron Beam Evaporators (Ebeams) are older pieces of equipment that were refurbished for Nano3 and are used for the deposition of thin films of precious metals such as Gold and Platium. In 2022, we replaced a significant amount of aging hardware on our two Ebeam units including:

> Replaced the high voltage (10kV) electron beam power supply with a more compact rack-mount Ferrotec unit

> Replaced the analog beam control mechanism with an advanced digital unit from Ferrotec

> Overhauled high vacuum and fluid connections (CDA, Compressed Helium, N2, cooling water).

> Further upgrades are ongoing, including a replacement for the vacuum controller system.

> Replacement of the E-beam gun and hearth is a semi-annual procedure.

> Dozens of calibration depositions were performed for various materials after the upgrades before returning the system to users.

An Ebeam Evaporator with the original bean controller and HVPS (left)

Lower end of Temescal Evaporator, including cryopump and HVPS delivery

Rebuilt emitter

Replacing hearth and turret in the lower end of the evaporator

Parylene Coater Refurbishment

In my final year at Nano3, one of my project assignments was the refurbishment of an SCS Parylene Coater, a tool used for packaging devices and wafers in parylene - a flexible packaging option preferred for its insulating and conformal characteristics. Our original parylene coater was one of our heaviest-used systems, due to long runtimes and high demand from a number of different labs and user groups.

In 2024 we purchased an upgraded coater from SCS, giving us time to bring our original unit down for maintenance. I stripped the machine down to the frame, replaced gauges, furnaces, and vacuum hardware, and then reassembled the system in a newly painted chassis.

Stripped machine frame before powdercoating

Front panel electronics to be removed and replaced on repainted chassis

Testing of rebuilt coater before installation in cleanroom

Wafer Holders

In the process of rebuilding the Denton 502A and 502B Evaporators, I designed and had manufactured some new custom tooling, including upper and lower 4" wafer holders for high throughput depositions.

Far Right: Upper end wafer holder with one populated carriage
Close Right: Lower end wafer holder with threaded insert carriers

Equipment Ownership

The following pieces of equipment are ones that I was primarily responsible for and gained comprehensive fluency in as an equipment engineer during my time at Nano3