Development of In-Situ Temperature Measurement Technology For MOCVD

• Main Authors: Lo,Yi-Ching, 羅憶青
• Other Authors: Yin,Ching-Chung
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/74960275052625015869

碩士 === 國立交通大學 === 機械工程系所 === 102 === This thesis studies the thermal radiation theory and applies its measuring technology for developing the in-situ high-temperature pyrometry with the reflectance correction. Measuring accuracy and precision improvements of the low radiation in 400-600°C are also investigated. In metal organic chemical vapor deposition (MOCVD) process, the mixed gases can react chemically and deposit on the wafer surface by applying sufficient heat. Therefore, temperature distribution of the wafer surface can affect the growth rate, epitaxial uniformity, thin film thickness, and wafer curvature, etc.. Moreover, owing to the generated defects during epitaxial process that cannot be reduced or eliminated by the following process and also influences the quality of end product, real-time feedback of temperature from wafer surface can compensate and improve this situation. This method also is one way to promote MOCVD process technology. Based on the Planck's theory of blackbody radiation, the near infrared (950 nm) thermal radiation signal is measured from the surface of silicon wafer specimen through the experimental method of geometrical optics. Reflectance of wafer surface used for the purpose of temperature correcting is also measured by using semiconductor laser with the same wavelength. In the temperature range of low radiation (400-600°C), because of lower signal-to-noise ratio, more measured temperatures are required for improving the accuracy and precision. In addition, the Sakuma-Hattori equation is used for estimating temperature via nonlinear regression. In the range of 500-600°C, the accuracy of former is up to ±2.66°C, and that of later is up to ±6.47 °C.