Non-toxic sol-gel processes of P- and N-type ZnO transparent conductive thin films

• Main Authors: Wen-Jie Wang, 王文杰
• Other Authors: Chih-I Wu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/07293932850873923910

碩士 === 國立臺灣大學 === 光電工程學研究所 === 99 === We investigate nontoxic fabrication processes to derive P and N-type ZnO transparent conductive thin films by sol-gel method and discuss how anneal condition effect the characteristics of P and N-type ZnO thin films. In the first part of the thesis, in order to fabricate P-type ZnO transparent conductive thin films, zinc acetate dehydrate was firstly dissolved in 2-propanol with ethanolamine as the stabilizer and ammonium acetate and indium(Ш) nitrate pentahydrate were used as co-doping materials. In three kinds of different anneal ambients(O2、N2 and vacuum), ZnO thin films exhibit p-type electrical properties only when they were annealed in oxygen ambient, with hole concentration of +1.58×10^17cm^-3、resistivity of 55.11Ω‧cm and carrier mobility of 0.72cm^2V^-1s^-1. The second part of the thesis describes the fabrication processes for N-type ZnO transparent conductive thin films. The preparation of precursor solution is similar to P-type ZnO, except that the doping material is only indium(Ш) nitrate pentahydrate. We discuss how different doping concentration(0.75%、1.00%、2.00%、3.00%、5.00%) and anneal ambients(O2、N2 and vacuum) effect the characteristics of N-type ZnO to get the better result. The result show that the N-type ZnO thin films with electron concentration of -1.35×10^18cm^-3、resistivity of 2.62Ω‧cm and carrier mobility of 1.77cm^2V^-1s^-1 at doping concentration of 2.00% in nitrogen ambient were achieved. On the other hand, the electrical properties of N-type ZnO thin films at doping concentration of 2.00% can be enhanced again with electron concentration of -2.34×10^19 cm^-3、resistivity of 2.16×10^-2Ω‧cm and carrier mobility of 12.33 cm^2V^-1s^-1 after first anneal in nitrogen ambient and second anneal in vacuum ambient.