FIBER-OPTICS BASED MICRO-PHOTOLUMINESCENCE SYSTEM

摘要

Spatially resolved photoluminescence apparatus (100) is used for the non-destructive characterization of a semiconductor sample (101). Photoluminescence excitation from a diode laser (110) is transmitted through a dichroic coupler (120) and in turn over a fiber to a fiber collimator (130) wherein the laser light is collimated into a pump beam prior to entering an air path. The air path is composed primarily of an objective lens (140). The objective lens (140) focuses the pump beam on the sample surface (101). The photoluminescence signal emitted by the sample travels the same path but in the opposite direction as the pump beam and is collected by the same fiber as a reflected signal. The dichroic fiber coupler (120) is used to separate the return signal from the pump beam with a low insertion loss for each beam. The return photoluminescence signal is fed to an optical spectrum analyser (160) using a single mode fiber connected to the coupler. The sample is placed on a rotational stage (150) capable of x, y, and z movement under computer control.