Mechanical Engineering Students Aim to Make Silicon Wafer Inspections More Efficient | Paul M. Rady Mechanical Engineering

Silicon Wafer Center Discovery Enhancement Team Members

  • Jack Carver – Project Manager
  • Dario Garcia – Logistics Manager
  • Prem Griddalur – System Engineer
  • Hank Kussin-Bordo – CAD Engineer
  • Marty LaRocque – Electromechanical Engineer
  • Ethan Plott – Chief Financial Officer
  • Noah Sgambellone – Test Engineer
  • Gavin Zimmerman – Software Engineer

Shortages of semiconductors – the computer chips that power products like smartphones, laptops, cars and even washing machines – continue to impact industries around the world.

Current supply chain issues are driving engineers to make inspections of the silicon wafers from which semiconductors are made more efficient. It’s a goal the industry would focus on even without the global shortage. To achieve this, mechanical engineering students at the University of Colorado have developed a device that improves the inspection process.

Seniors in the mechanical engineering department built a silicon wafer center search enhancement device for KLA, a semiconductor manufacturing company. The senior design team’s prototype uses two cameras to capture the edge of the circular wafer, along with computer software to calculate the radius and find the center of the wafer.

“The reason this is important is that KLA needs to inspect these wafers for defects, and when they find one, they need to know where it is on the wafer with a high level of accuracy” , said Marty LaRocque, the team’s electrical technician. mechanical engineer. “They have to establish a coordinate system on the wafer and the hardest part is finding the center.”

Marty LaRocque examines the team’s silicon wafer center research enhancement device.

Silicon wafer inspection
The device uses two cameras to capture the edge of the wafer.

Currently, KLA detects the center of the wafer with ten different images around the edge. The student team designed their device to find the center just as efficiently with just two images.

“On one of KLA’s inspection tools, it currently takes them eight seconds to align a wafer, and we’re trying to reduce that time to two seconds,” said project manager Jack Carver. “A 75% reduction is going to get a lot more throughput. With the global shortage of silicon wafer supply, any improvement in this area would be of great benefit to them.

The real impact the student device could have on the industry is part of why this project appealed to them.

“It’s interesting because KLA explained to us the true meaning of our prototype,” said Prem Griddalur, the team’s system engineer. “About every two years, the size of semiconductors decreases, and at the same time, the scale at which they manufacture them increases due to the increase in demand. KLA has done a great job of explaining why their equipment is important and how our project plays a part in the larger scheme of the industry. »

The team captured its first position from the center of the pad in early March. They are now performing statistical tests and taking measurements to verify the accuracy of the device. They need the coordinates to be within 10 microns of the true center, which is the width of a human red blood cell.

Since the team’s device is a prototype, KLA’s system may not look exactly like the students’ design. However, their prototype and testing will still provide the company with critical information to guide decisions about future designs.

The students said that this aspect is related to real-world scenarios. Typically, engineers are tasked with improving current systems, rather than creating new designs from scratch.