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  • Demonstration of Si-doped Al-rich regrown Al(Ga)N films on AlN/sapphire with >10^15/cm3 carrier concentration using CCS-MOCVD reactor

This content will become publicly available on November 25, 2025

Title: Demonstration of Si-doped Al-rich regrown Al(Ga)N films on AlN/sapphire with >10^15/cm3 carrier concentration using CCS-MOCVD reactor
Thin Si-doped Al-rich (xAl > 0.85) regrown Al(Ga)N layers were deposited on AlN on sapphire template using metal-organic chemical vapor deposition (MOCVD) techniques. The optimization of the deposition conditions, such as temperature (1150 °C), V/III ratio (750), deposition rate (0.7 Å/s), and Si concentration (6 × 10^19/cm3), resulted in a high charge carrier concentration (> 10^15 cm−3) in the Si-doped Al-rich Al(Ga)N films. A pulsed deposition condition with pulsed triethylgallium and a continuous flow of trimethylaluminum and ammonia was employed to achieve a controllable Al composition xAl > 0.95 and to prevent unintended Ga incorporation in the AlGaN material deposited using the close-coupled showerhead reactor. Also, the effect of unintentional Si incorporation on free charge carrier concentration at the regrowth interface was studied by varying the thickness of the regrown Al(Ga)N layer from 65 to < 300 nm. A maximum charge carrier concentration of 4.8 × 10^16 and 7.5 × 10^15/cm3 was achieved for Al0.97Ga0.03N and AlN films with thickness <300 nm compared to previously reported n-Al(Ga)N films with thickness ≥400 nm deposited using MOCVD technique.  more » « less
Award ID(s):
2338683
PAR ID:
10603860
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
AIP publishing
Date Published:
Journal Name:
Applied Physics Letters
Volume:
125
Issue:
22
ISSN:
0003-6951
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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