公开(公告)号：US20250109524A1

公开(公告)日：2025-04-03

申请号：US18477737

申请日：2023-09-29

Applicant: Wisconsin Alumni Research Foundation

Inventor： Shubhra S. Pasayat ,  Chirag Gupta ,  Swarnav Mukhopadhyay ,  Cheng Liu

IPC: C30B25/16 ,  C30B25/18 ,  C30B29/40

Abstract: Methods for growing semi-insulating, carbon-doped (C-doped) group III-nitride on a substrate via metal-organic chemical vapor deposition (MOCVD) are provided. In the methods, the controlled timing of the introduction of carbon dopant precursors in the MOCVD growth process results in semi-insulating group III-nitride having a high crystal quality and surface morphologies. Some embodiments of the methods use a carbon dopant precursor pre-flow step in which a carbon dopant precursor is introduced into the MOCVD reactor chamber prior to the introduction of any group III precursors and the onset of film formation (“Pre-Flow”). In other embodiments of the methods, the introduction of carbon dopant precursors is delayed until after the onset of group III-nitride film coalescence (“Delayed-Doping”).

公开(公告)号：US20240363745A1

公开(公告)日：2024-10-31

申请号：US18308386

申请日：2023-04-27

Applicant: Wisconsin Alumni Research Foundation

Inventor： Chirag Gupta ,  Swarnav Mukhopadhyay ,  Shubhra Shweta Pasayat ,  Jiahao Chen

IPC: H01L29/778 ,  H01L29/06 ,  H01L29/20

CPC classification number: H01L29/7786 ,  H01L29/0607 ,  H01L29/2003

Abstract: Group III-nitride based high electron mobility transistors (HEMTs) are provided. The HEMTs combine a high-aluminum-content barrier layer with a recessed gate that provides the HEMTs with a very low channel sheet resistance and enables high-power, high-frequency operation. A thick barrier layer increases the distance between the two-dimensional electron gas (2DEG) channel and traps at the exposed surface of the group III-nitride barrier layer, thereby reducing or eliminating current collapse. The recessed gate provides a reduced barrier layer thickness below the gate, reducing the distance between the gate and allowing for good modulation of the 2DEG by the gate.