The performance limits of any semiconductor device are decided by the semiconductor materials used in the device, processes used to fabricate the device, and physics of device operation.
In the group, we explore new semiconductor materials aiming to:
- Increase efficiency and operation limits of existing semiconductor devices
- Enable new device functionalities and applications.
With above objectives in mind, the group is currently focusing on wide-bandgap and phase-transition (metal-insulator, ferroelectric etc.) materials and devices.
Of special interest are following oxide semiconductors:
1. Vanadium Dioxide (VO2) : VO2 is a phase change material which undergoes a reversible insulator-metal phase transition at ~68 ºC. This phase change is associated
with large change in resistivity and optical reflectance leading to many novel electronic and optical applications. We have developed a low thermal budget method to synthesize VO2 thin films
and are actively working on demonstrating various electronic, RF, optical (both visible and IR) devices based on VO2.
2. Gallium Oxide (β-Ga2O3) : β-Ga2O3 is an ultra wide-bandgap semiconductor (Eg :4.5-4.8 eV) with applications in power electronics, deep ultra violet photodetectors, and harsh environment sensors.
Unlike other wide bandgap semiconductors such as GaN and SiC, β-Ga2O3 single crystals can be grown using low cost melt-growth methods which gives it an economical advantage in addition to the material advantage due to its large bandgap
and high breakdown electric field (~ 7-8 MV/cm). We are involved in epitaxial growth of this material using Low Pressure Chemical Vapour Deposition (LPCVD) and are actively working on developing high power devices and solar-blind photodetectors.
Research Facilities
- Thin Film Deposition: DC/RF/Pulsed-DC Magnetron Sputtering, Low Pressure Chemical Vapour Deposition (LPCVD) System, Multi-turret Thermal Evaporator
- Processing: Fume Hoods, Spin-coater, Hot-plates & Ovens, Photo-lithography, Direct Laser Writer, MJB3 Karl Suss Mask Aligner, Glove Box, 3D Printer, Laser Engraver, Analytical Balance, Annealing furnace etc.
- Characterization : Temperature Dependent Four-point probe, Hall-Effect, Ocean Optics Spectrometer, Deuterium-Halogen Light Source, Optical Microscope, Oscilloscopes, Signal Generator, Source-Measure Unit, Probe-station with heating/cooling chuck etc.
Advanced Center for Materials Science (https://www.iitk.ac.in/acms/facility.html)
Center for Nanoscience (https://www.iitk.ac.in/nanoscience/Equipment.html)
MSE Raman Facility (https://www.iitk.ac.in/mse/MSE-Facilities/Raman/)
MSE HRXRD Facility (https://www.iitk.ac.in/mse/XRD/panalytical/panalytical.html)
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