精确确定半导体材料临界点的能量值

分析表明波长调制反射谱的实质，是介电函数对能量的一级微商。导出了弱电场调制反射谱与介电函数对能量的三级微商成正比，将ＭＯＣＶＤ方法生长的ＧａＩｎＰ以及掺Ｓｉ和掺Ｚｎ三个样品，用椭偏光谱法测量得到可见光区的介电函数谱，并求其一级和三级微商谱。将用于分析电反射谱的三点法推广用于分析介电函数的一级和三级微商谱，得到波长调制和弱电场调制反射谱的实验结果，并与介电函数谱的结果加以比较，使灵敏度和分辨率有很大提高

Accurate determination on energy at critical point of semiconductor materials

It is shown that the wavelength modulated reflective spectrum is essentially the first derivative of dielectric function with respect to the energy. It was derived that the modulated reflective spectrum of weak electric field is proportional to the third derivative of the dielectric function with respect to the energy. The dielectric function spectra for GaInP and doped Si or Zn GaInP samples grown by MOCVD are obtained in the visible region by using the ellipsometric spectroscopy, and the first and third derivative spectra are evaluated. Extending the three-point-scaling used in analyzing the electric reflective spectrum, the first and third derivative spectra of the dielectric functions can be analyzed. The experimental results of reflective spectra of wavelength modulation and weak electric field modulation are obtained and are compared with that of dielectric function spectra,which shows that the sensitivity and resolution are remarkably improved.