Comparison of PIn and NIp AlGaN UV photodiodes for solar-blind performance

In this paper, n-i-Al/sub 0.33/Ga/sub 0.67/N/p-GaN (NIp) photodiode structures are examined as an alternative to p-i-Al/sub 0.33/Ga/sub 0.6/7N/n-GaN (PIn) structures for improved signal rejection for wavelengths longer than 300 nm in UV solar-blind detectors. The effect of incorporating an additional Al/sub 0.33/Ga/sub 0.67/N layer for barrier enhancement at the heterointerface of NIp photodiodes is also evaluated. It is shown that even with the inclusion of a barrier enhancement layer, PIn structures are better suited for solar blind detection given the limitation in the growth of doped thick Al/sub 0.33/Ga/sub 0.67/N layers.