Venkatesh Moka

Topic: Temperature dependent minority carrier lifetime measurement on wide bandgap semiconductors Performing and interpreting of temperature and spatial dependent minority carrier lifetime measurements on different sample series of GaN and AlGaN. Investigation of the microwave response to different sheet resistivities of the beforementioned sample series with varying doping densities.

Measurement of carrier lifetime, photoconductivity, the resistivity of bricks and wafers by Microwave Detected Photoconductivity. Measurement of Resistivity and Reflectivity of wide bandgap semiconductor samples. Calibrating the sensors used for Resistivity and Reflectivity measurements.

Research assistant in the Metrology team Perform different measurements related to topographies of 300- and 200-mm wafers in cleanroom (class 10 - 1000) Microscopic and topographic inspection of incoming and outgoing wafers Data analysis and data evaluation of roughness, topographies, defects, etc. of wafers Analysis of the measurements (using Origin and other software) and drawing conclusions based on results Preparing presentations with the summaries of results and conclusions

Deep Reactive Ion Etching (DRIE) of Silicon using Bosch Process and Positive Profile Etching Process. Involved in Process Development and Optimisation of the etching process for the etching of High Energy X-Ray lenses. Etching of MEMS Structures, Microfluidic chips, and Through Silicon Vias (TSVs) with high aspect ratios. Well versed with various tools and techniques involved in the Fabrication of Semiconductors. First-hand experience in the cleanroom.

Topic: Creation of high-energy-X-ray-lenses by deep reactive ion etch in silicon. Optimized and developed a novel sequence of deep reactive ion etching process, which can be used for the fabrication of high-energy-X-ray –lenses with high precision and quality. The newly optimized process can be used to produce highly anisotropic structures with a tilt angle of 90 degrees and an etch depth of 700-900 µm.