High-Temperature and High-Electron Mobility Metal-Oxide-Semiconductor Field-Effect Transistors Based on N-Type...

Area of Science:

• Materials Science
• Semiconductor Physics
• Electrical Engineering

Background:

• Diamond exhibits superior material properties for next-generation electronics compared to silicon.
• Achieving diamond complementary metal-oxide-semiconductor (CMOS) devices requires both n-type and p-type conductivity.
• Development of n-channel metal-oxide-semiconductor field-effect transistors (MOSFETs) in diamond has been a significant challenge.

Purpose of the Study:

• To fabricate an electronic-grade phosphorus-doped n-type diamond epilayer.
• To demonstrate n-channel diamond MOSFETs for the advancement of diamond CMOS technology.

Main Methods:

• Fabrication of an atomically flat, phosphorus-doped n-type diamond epilayer using step-flow nucleation.
• Characterization of the fabricated n-type diamond epilayer and demonstration of n-channel MOSFETs.

Main Results:

• Successful fabrication of electronic-grade n-type diamond with an atomically flat surface.
• Demonstration of n-channel diamond MOSFETs.
• Achieved high field-effect mobility of approximately 150 cm² V⁻¹ s⁻¹ at 573 K, the highest for n-channel wide-bandgap semiconductor MOSFETs.

Conclusions:

• This work overcomes a critical hurdle in realizing diamond CMOS technology.
• Enables the development of energy-efficient, high-reliability CMOS integrated circuits for demanding applications.
• Paves the way for high-power electronics, integrated spintronics, and extreme sensors in harsh environments.