Fabrication of Si/ZnO Vertical n-n + and p-p + Isotype Junction Devices by 1 Pulsed Laser Deposition 2 Saeed Esmaili Sardari * , Andrew Berkovich, and Agis A. Iliadis 3 Department of Electrical & Computer Engineering, University of Maryland, College Park, MD 4 20833 5 *Corresponding Author: saeedesmaili@yahoo.com 6 Keywords— ZnO, Widegap Semiconductors, Vertical Transport, Junction Devices, ZnO on 7 Silicon 8 9 Abstract—Device development and electrical characterization of high quality zinc oxide (ZnO) 10 thin films grown on silicon (100) substrates are presented in this paper. Thin films of ZnO are 11 grown at an optimized growth temperature of 300 o C and two oxygen overpressure regimes on n 12 and p-type Si substrates by pulsed laser deposition technique. Current-voltage characteristics of 13 four devices are investigated by deposition of silver contacts on ZnO films and back gating the 14 substrates. Rectifying properties are observed for two devices: one, for the n-Si substrate device 15 with the film grown at low (6.66×10 -4 Pa) oxygen overpressure and two, for the p-Si device with 16 ZnO grown at high (3.33×10 -2 Pa) oxygen. For the other two devices, namely the devices with 17 the films grown on n-Si at high oxygen and p-Si at low oxygen pressure less pronounced 18 rectifications are observed. Forward bias currents follow a quadratic current-voltage (IV) 19 relationship, and this is in agreement with space-charge-limited current transport theory. Our 20 results confirm the effects of the growth conditions including oxygen overpressure and growth 21 substrate on intrinsic carrier concentrations and, hence, electrical properties of ZnO thin films. 22 We conclude that output characteristics of Si/ZnO junction devices can be adjusted by 23 modifications of growth conditions to create p-n equivalent junctions. The results have 24 significant contributions to the development of future ZnO-based devices. 25 © 2015. This manuscript version is made available under the Elsevier user license http://www.elsevier.com/open-access/userlicense/1.0/