Microstructure effects on quantum efficiency in PtSi/p-Si(100) Schottky barrier detector

Abstract

The microstructure effects on the performance of the PtSi Schottky barrier detector (SBD) have been investigated in detail. The growth temperatures were ranged from 350 to 550 degreesC. The thickness of the PtSi film measured by high resolution transmission electron microscopy (HRTEM) is around 4 nm. The electron diffraction pattern shows an intermingling of both (1 (1) over bar 0) and (I (2) over bar 1) orientations when the PtSi film is formed at 350 degreesC. However, the diffraction patterns show only (1 (2) over bar1) orientation when the PtSi films are formed above 450 degreesC. It was found that the electrical barrier height of the Schottky barrier detector formed at 350 degreesC is about 0.02 eV higher than that formed above 450 degreesC. The microstructure of the PtSi film does not change even though the formation temperature is further increased to 550 degreesC. Nevertheless, the higher the formation temperature, the larger is the grain size. It was also observed that the grain size does not change the electrical barrier height. However, the quantum efficiency of the detector is much higher if the grain size is larger. The results indicate that the quantum efficiency of the detector can be improved if the PtSi film has (1 2 1) orientation and larger grain size. (C) 2001 Elsevier Science B.V. All rights reserved.