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

The microstructure effects on the performance of the PtSi Schottky barrier detector (SBD) have been investigated in detail. The growth temperatures we re 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) ov er 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 ba r1) orientation when the PtSi films are formed above 450 degreesC. It was f ound that the electrical barrier height of the Schottky barrier detector fo rmed at 350 degreesC is about 0.02 eV higher than that formed above 450 deg reesC. The microstructure of the PtSi film does not change even though the formation temperature is further increased to 550 degreesC. Nevertheless, t he higher the formation temperature, the larger is the grain size. It was a lso observed that the grain size does not change the electrical barrier hei ght. However, the quantum efficiency of the detector is much higher if the grain size is larger. The results indicate that the quantum efficiency of t he detector can be improved if the PtSi film has (1 2 1) orientation and la rger grain size. (C) 2001 Elsevier Science B.V. All rights reserved.