Dresden 2006 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

HL: Halbleiterphysik

HL 50: Poster II

HL 50.68: Poster

Thursday, March 30, 2006, 16:30–19:00, P3

Optical beam indal npn-structure junction devicesuced current measurements at planar two-dimension — •C. Werner, D. Reuter, and A.D. Wieck — Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, 44780 Bochum

By overcompensating a p-doped GaAs/In_0.19Ga_0.81As/Al_0.33Ga_0.67As pseudomorphic heterostructure we have fabricated two-dimensional npn-junction devices. The molecular beam epitaxy grown base material has a hole density of 7×10¹¹ cm⁻² and the mobility of the holes is 200 cm²/Vs at room temperature.

By implanting silicon ions we locally overcompensate the heterostructure, as described in [1, 2], and obtain n-doped areas. The implantation consists of two rectangles with a non-implanted area in between. We expect the resulting photocurrent to be linearly dependent on the position of a light spot for this type of sample. Therefore we made OBIC-measurements (optical beam induced current) by scanning a modulated focused laser beam (635 nm) across the sample perpendicular to the junctions and measuring the voltage drop over a resistance connected to the device by a lock-in amplifier.

This project is gratefully acknowledged by the Evangelische Studienwerk "Haus Villigst" within the "Promotionsschwerpunkt Wechselwirkungen".

[1] D. Reuter, C. Werner, C. Riedesel, A. D. Wieck, D. Schuster, and W. Hansen, Physica E 22 (2004) 725.

[2] D. Reuter, C. Werner, A. D. Wieck and S. Petrosyan, Appl. Phys. Let. 86 (2005) 162110.