METHOD FOR MEASURING INFRARED ABSORPTION OF SILICON CRYSTAL

摘要

PURPOSE:To enable correct estimation by using a specific mid-infrared ray segment to calculate and analyze a differential spectrum of deposited oxygen absorption and a differential spectrum of oxygen impurity absorption by means of respective absorption spectra of oxygen impurity and deposited oxygen and oxygen impurity as well as spectra of oxygen and oxygen impurity as well as spectra of oxygen impurity and deposited oxygen and oxygen impurity. CONSTITUTION:An oxygen impurity absorption spectrum of a silicon crystal before heat treatment and an oxygen impurity and deposited oxygen absorption spectrum of the silicon crystal after the heat treatment are measured. Then a differential spectrum in deposited oxygen absorption is calculated by means of a mid-infrared ray segment of 515 cm<-1>, while a differential spectrum in oxygen impurity absorption is calculated by means of the oxygen impurity and despoisted oxygen absorption spectrum and a deposited oxygen absorption spectrum. The separated spectra are used to know a deposition amount of deposit and to estimate and analyze it. The analysis results based on correct differential spectra allow correct estimation.