Structure for a gallium nitride (GaN) high electron mobility transistor

摘要

A high-electron mobility transistor (HEMT) device employing a gate protection layer is provided. A substrate has a channel layer arranged over the substrate and has a barrier layer arranged over the channel layer. The channel and barrier layers define a heterojunction, and a gate structure is arranged over a gate region of the barrier layer. The gate structure includes a gate arranged over a cap, where the cap is disposed on the barrier layer. The gate protection layer is arranged along sidewalls of the cap and arranged below the gate between opposing surfaces of the gate and the cap. Advantageously, the gate protection layer passivates the gate, reduces leakage current along sidewalls of the cap, and improves device reliability and threshold voltage uniformity. A method for manufacturing the HEMT device is also provided.

主权项

1. A high-electron mobility transistor (HEMT) device comprising:
a substrate having a channel layer arranged over the substrate and having a barrier layer arranged over the channel layer, wherein the channel and barrier layers define a heterojunction; a gate structure arranged over a gate region of the barrier layer, the gate structure including a gate arranged over a cap, wherein the cap is disposed on the barrier layer and comprises a planar upper surface, wherein the planar upper surface extends laterally between opposing sidewalls of the cap that underlie the planar upper surface, and wherein the gate protrudes towards the cap to culminate at a lower surface overlying the planar upper surface; and a gate protection layer arranged along the sidewalls of the cap, and arranged below the gate, wherein the gate protection layer continuously covers the planar upper surface to separate the planar upper surface of the cap and the lower surface of the gate.