Processing Technologies for Al(x)Ga(1-x)N Photodetector Arrays
Abstract
Processing technologies for Al(x)Ga(1-x)N have been developed. Inductively-coupled-plasma reactive ion etching (ICP-RIE) is shown to be capable of etching AlGaN materials at high etch rates and high anisotropy Plasma-induced damage in n-GaN is shown to depend mainly on the ion energy to which samples are exposed during ICP-RIE The damage can be annealed at 700 degrees C with samples recovering to their unetched states. Photoelectrochemical etching of n-GaN is shown to be useful for material characterization and this process may be exploited as a rapid method for quantification of defects in GaN Auger analysis and x-ray photoelectron spectroscopy have been utilized for studying the cleaning of Al(x)Ga(1-x)N surfaces; it is shown that buffered oxide etch is more effective in removing surface adventitious oxides of Al(x)Ga(1-x)N than ammonium hydroxide and hydrochloric acid. Schottky contacts on Al(x)Ga(1-x)N for various metals have been characterized. The barrier heights depend on metal work function which may show that Al(x)Ga(1-x)N surfaces are not completely dominated by surface states. Low contact ohmic resistances were achieved on p-GaN and p- Al(x)Ga(1-x)N /GaN superlattices using Ti/Pt/Au metallization. Ti/Al/Mo/Au metallization was developed as a robust ohmic contact metallization for n- Al(x)Ga(1-x)N with x up to 0.6.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2002
- Accession Number
- ADA413407
Entities
People
- Ilesanmi Adesida
Organizations
- University of Illinois Urbana–Champaign