This internship was focused on precision mechanical and controls engineering at KLA, a semiconductor equipment manufacturer.

Details

The main mechanical design project involved redesigning a 2-DOF flexure for the assembly and adjustment of a quarter wave plate. The new design achieved 3.6x greater flexibility than the previous solution, with a resolution of 2.5 micro-radians. Preformance was simulated with FEA to verify range of motion, and that stresses were bellow the vimises yeild criterion. On the controls side, the work involved precision tuning of an air bearing motor system, successfully doubling the motor speed to 40Hz while achieving a 3-sigma following error of ~55 micro-radians — a 20 micro-radian improvement over the previous implementation. The first bending mode of the system was also characterized from experimental stiffness data, and a custom FFT analyzer was implemented in MATLAB with rectangular windowing to assess the system’s frequency response. This FFT exersize allowed me to discover that an internal motor clibration tool was implemented incorrectly, and the software team could correct the error. The internship also included corporate training from MIT professor Alexander Slocum, where kinematic coupling and athermal design principles were applied to develop a precision mirror mounting solution.