סמינר: Graduate Seminar
Development of Oxide Transistors for Cryogenic Electronics
Lecturer:
Shay Zimmerman
Research Areas:
| Conventional silicon CMOS technologies suffer from carrier freeze-out at cryogenic temperatures, limiting their suitability for emerging low-temperature electronic systems such as quantum computing control and readout hardware. Complex oxides, and in particular SrTiO₃ (STO), offer an alternative platform due to their large dielectric constant and strongly enhanced carrier mobility at low temperatures. In this work, we design, develop and fabricate depletion-mode field-effect transistors using oxide electronics. Our channel is based on a vacancy-induced quasi-two-dimensional electron gas (quasi-2DEG) in SrTiO3, and the design is implemented using scalable, fab-compatible fabrication flow.
The conducting channel is generated via NH₃ plasma reduction prior to atomic layer deposition (ALD), enabling tunable carrier densities while maintaining high mobility from room temperature down to cryogenic temperatures without carrier freeze-out. Integrating a vacancy-engineered channel into a transistor architecture, however, introduces significant challenges related to electrostatic control, leakage currents, vacancy stability, and device isolation. Through combined optimization of vacancy engineering, gate dielectric design, and device geometry, we achieve robust depletion-mode operation with I on/I off ratios reaching up to five orders of magnitude at cryogenic temperatures. M.Sc. student under the supervision of Prof.Lior Kornblum.
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