Analysis of InAl(Ga)N/GaN wet-etching by structural, morphological and electrical methods

作者：Brazzini T^*; Martin Horcajo S; Romero M F; Gacevic Z; Calle F

来源：Semiconductor Science and Technology, 2014, 29(7): 075003.

DOI：10.1088/0268-1242/29/7/075003

• InAlGaN/GaN
• AlInGaN/GaN
• wet etching
• nitride HEMT
• recessed-gate
• InAlN/GaN
• normally off

Wet etching of InAl(Ga)N/GaN structures has been studied in detail by means of Rutherford backscattering spectroscopy, x-ray diffraction, atomic force microscopy and capacitance-voltage profiling (C-V). The samples used for the study were grown on three different substrates (sapphire, silicon carbide and silicon(111)). Nearly lattice-matched compositions were measured for all the samples. We obtained different etching rate depending on the homogeneity and root-mean-square roughness of the surface as well as the underlying substrate, attributing the difference possibly to the presence of threading dislocation in the sample. The study interest is correlated to the possibility to control at a very precise level the thickness etching of the material, making it possible to fabricate normally-off recessed gate high-electron-mobility-transistors.

• 出版日期2014-7