基于LabVIEW的外延片光致发光扫描系统

概述了一套基于LabVIEW而搭建的半导体光致发光扫描系统.充分考虑扫描过程中由于外延片荧光信号过于微弱、不均匀背景光噪音可能产生的光谱采集失真以及随后分析谱图所存在的物理参量读取误差等因素,通过扣除背光源、隔离样品、高斯拟合等方式对测量过程进行优化.同时依托LabVIEW自身强大的仪器控制能力,如调用动态链接库与ActiveX控件实现了对光谱仪和平移台的通信与控制,结合其良好的数据分析及显示能力,实现了对外延片测量、读取、分析处理以及实时显示等过程的自动化整合,准确高效地提取出样品空间分辨的光致发光特性如峰位、光强等.最后初步分析了所用外延片的发光均匀性,得出波长分布与生长温度分布基本一致,肯定了保持生长腔内温度均匀一致的重要性.该系统不仅界面友好、简单易操作、实时性强、智能化高且搭建简单易行,极大地降低了成本,方便研究人员进行快捷准确的测试.

PL-Mapping of the Epitaxial Wafer System Based on LabVIEW

A set of semiconductors photoluminescence scanning(PL-Mapping)system using LabVIEW8 is summarized. In consideration of the spectra collected distortion originate from excessive weak fluorescent signal of epitaxial wafers, inhomogeneous background illumination noises and then the inaccurate physical parameters in spectra analysis and others,methods for optimizing system such as backlight deduction, sample isolation, Gaussian fitting are developed. The communication and control with the spectrometer and motorized is realized with the help of strong ability of instrument control such as calling DLL and ActiveX in LabVIEW. Owing to the same wonderful ability in data analysis and display, the process of measuring, read, analysis and real-time display is easily integrated into an interface, hence the optical property of sample on spatial discrimination is obtained effectively and efficiently. Finally luminance uniformity of epitaxial wafer is preliminary analyzed. Wavelengths agree with temperatures distribution, which affirm the importance of maintaining consistent temperature in growth chamber. It is a system friendly interfaced, easy to use, high real-time and built simply, which offers researcher accurate and rapid measurement.