Effects of ZnO seed layer annealing temperature on the properties of n-ZnO NWs/Al(2)O(3)/p-Si heterojunction.

Effects of ZnO seed layer annealing temperature on the characteristics of the n-ZnO nanowires/Al(2)O(3)/p-Si heterojunction are investigated. Well-aligned ZnO nanowires (NWs) are grown through a simple hydrothermal method. Both the insertion of Al(2)O(3) buffer layer and the annealing treatment of ZnO seed layer are advantageous for the growth of ZnO NWs. This leads to a relatively high rectification ratio of up to 7.8 × 10(3) at ± 4.0 V in ZnO NWs/Al(2)O(3)/p-Si heterojunction photodetectors. The photoelectrical property of n-ZnO/p-Si photodetectors with an enhanced UV/dark current ratio as high as 30 under a reverse bias of 4.0 V is obtained.