The Evolution of Manufacturing Technology for GaN Electronic Devices

Area of Science:

• Semiconductor Device Physics
• Materials Science
• Electronics Engineering

Background:

• Gallium Nitride (GaN) is crucial for high-power and high-frequency devices due to its superior electrical properties.
• GaN High Electron Mobility Transistors (HEMTs) are established for RF power amplification, utilizing traditional gold-based manufacturing.
• Growing demand for GaN devices in power electronics and 5G communications necessitates scalable, CMOS-compatible fabrication.

Purpose of the Study:

• To review the historical development and principles of conventional GaN HEMT processes with gold metallization.
• To discuss the evolution and current status of CMOS-compatible, gold-less GaN device technologies.
• To highlight novel techniques and future directions, including vertical GaN devices.

Main Methods:

• Review of established unit processes for GaN HEMT fabrication (epitaxy, ohmic contacts, Schottky gates).
• Analysis of advancements in CMOS-compatible, gold-less metallization schemes.
• Examination of innovative techniques like regrown ohmic layers, MIS gates, and p-GaN gates.
• Discussion of emerging vertical GaN device architectures.

Main Results:

• Conventional GaN HEMT technology relies on gold-based processes.
• CMOS-compatible, gold-less techniques are advancing, enabling high-volume production.
• Novel methods such as regrown ohmic layers and p-GaN gates offer enhanced device performance.
• Vertical GaN devices represent a promising new frontier for high-power applications.

Conclusions:

• The transition from conventional gold-based to CMOS-compatible, gold-less processes is vital for scaling GaN device manufacturing.
• Innovations in device structures and materials are driving performance improvements and expanding application scope.
• Future research and development in GaN technology, including vertical devices, will continue to push the boundaries of power and frequency capabilities.