화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.154, No.5, H336-H339, 2007
Comparison of e-beam and sputter-deposited ITO films for 1.55 mu m metal-semiconductor-metal photodetector applications
The optical and electrical properties and surface morphology of sputtered, E-beam deposited, and composite E-beam/sputtered indium-tin-oxide (ITO) films for metal-semiconductor-metal (MSM) photodetector applications were compared. The resistivity of sputtered ITO was almost 2 orders of magnitude less than that of E-beam-deposited ITO, while the resistivity of the composite films was only 15% higher than that of sputtered films. The transmittance at 1.55 mu m of sputtered and composite ITO films was 83 and 77%, respectively, which was much higher than the value of 13% for the E-beam-deposited ITO. The composition of ITO films for both deposition techniques was very similar, as determined from Auger electron spectroscopy surface scans and depth profiles. The sputtered films showed much smoother surfaces and smaller grain size. InGaAs-based MSM devices with ITO fingers have been fabricated and showed higher photo response than that of MSM devices with conventional Ti/Au fingers. (c) 2007 The Electrochemical Society.