Developing ultrawide-bandgap semiconductor devices with emphasis on h-BN neutron detectors and AlN:Zr photoconductive semiconductor switches, covering device fabrication, process development, electrical/optical characterization, packaging, and performance optimization.

• Developed millimeter-thick and multi-stacked h-BN semiconductor detectors for thermal and fast-neutron detection, including direct detection of 14.1 MeV D-T fusion neutrons.

• Fabricated, packaged, and characterized h-BN radiation detectors using semiconductor processing, metal deposition, dry etching, wire bonding, and high-voltage electrical measurements.

• Investigated charge-carrier transport and electrical/optical properties of quasi-bulk h-BN and AlN:Zr ultrawide-bandgap semiconductor devices.

• Designed and executed process-development experiments for h-BN by varying etch conditions, annealing temperature/time, metal/contact conditions, device geometry, photoresist/process conditions, laser power, and material thickness; correlated process parameters with electrical/optical device performance to identify optimized conditions and recommend process changes.

• Troubleshot semiconductor fabrication processes and equipment, evaluated material/device performance across process splits, and documented experimental procedures, process conditions, results, and corrective actions for repeatable device fabrication.

• Developed and tested AlN:Zr photoconductive semiconductor switch structures with >3.3 kV hold-off voltage and ~4.88 A peak current.

• Installed, maintained, and troubleshot semiconductor fabrication and characterization equipment; translated completed research into peer-reviewed publications.

Semiconductor Fabrication

Mask aligner/ wafer processing

• Photolithography

• Dry etching

• Metallization

• Wire bonding

• Device packaging

• High-voltage device fabrication

Process Development

ICP etcher or process flow

• Etch-condition optimization

• Annealing temperature/time

• Contact optimization

• Photoresist/process conditions

• Device geometry

• Material thickness

Device Characterization

Keithley / optical setup

• I–V characterization

• Photocurrent

• High-voltage measurements

• Charge transport

• Optical characterization

• Performance comparison

Radiation Detection

h-BN detector or neutron setup

• Thermal neutron detection

• Fast neutron detection

• 14.1 MeV D-T neutrons

• Pulse-height measurements

• Charge collection

• Detector-efficiency analysis