Figures

Figure 1

A schematic, cross-sectional diagram showing a GaN/Al2O3 layer with a small hole used for thickness measurements.

Figure 2

Profiles of mobility µ, carrier concentration n, O concentration [O], and Si concentration [Si] in a GaN/Al2O3 layer grown by HVPE. The interface is at depth = 0.

Figure 3

Temperature dependences of the (apparent) mobility µas-grown of an as-grown GaN/Al2O3 layer, about 6-µm thick, and the (apparent) mobility µetched of the same layer etched to a thickness of 0.75 µm. Also shown are µD-H, which is the average mobility of the top 5 µm, as determined by differential-Hall measurements, and µB-I, which is the average mobility of the "bulk" region (also approximately the top 5 µm), calculated by correcting µas-grown for the degenerate interface layer.

Figure 4

Temperature dependences of the (apparent) carrier concentration nas-grown of an as-grown GaN/Al2O3 layer, about 6-µm thick, and the (apparent) carrier concentration netched of the same layer etched to a thickness of 0.75 µm. Also shown are nD-H, which is the average carrier concentration of the top 5 µm, as determined by differential-Hall measurements, and nB-I, which is the average carrier concentration of the "bulk" region (also approximately the top 5 µm), calculated by correcting µas-grown for the degenerate interface layer.

© 2001 The Materials Research Society