STUDY OF MORPHOLOGICAL DISTRIBUTION OF DEFECTS IN GaAs WAFERS BY INFRARED DIGITAL IMAGE PROCESSING
红外数字图象处理技术用于研究砷化镓材料中的缺陷形态分布

A new method is applied to characterize the defects in GaAs material (e.g. the absorption of EL2 centres). The method consists of transmitting a laser beam (A=l.1-1.5 urn) through the GaAs wafer of 4-8 mm thickness and 50 mm diameter. The image is received by the TOSHIBA 8844 camera and entered into the DATASUD computer image processing system. This image is displayed on a monitor permitting to observe the inhomogeneity (like cross, cells and volutes) of the EL2 and dislocation defects. This paper will introduce a specific image processing software for GaAs material, called ZH1MAG (ZHang IMAGe) and its applications in GaAs wafer. The software can be also applied to any other types of image processing.