Presentation Information
[19p-B201-7]Measurement of carbon concentration in silicon crystal, 2-nd generation
(26) Measurement of 1012/cm3 difference in 1013/cm3 synthetic samples by IR
〇Naohisa Inoue1, Shuichi Okuda1, Shuichi Kawamata1 (1.Radiation research Center, Osaka Metropolitan Univ.)
Keywords:
silicon crystal,carbon concentration,infrared absorption
We have developed 2-nd generation IR to measure below 5x1014/cm3. It includes (1) Preparing known and negligible concentration of about 1013/cm3 by electron irradiation. (2) Instrument test to evaluate instrumental detection limit and spectral DL. (3) Repeated scan and average to improve S/N. (4) Deletion of unwanted outer and inner phonon bands by mathematical processing of differential spectrum of test and reference. Here, by adjusting weighted difference and short baseline, (1) 1013/cm3 difference in 1014/cm3 sample was obtained by 600-608-615 cm-1 3-point baseline. (2) 1012/cm3 difference in 1013/cm3 synthetic samples was obtained by asymmetrically weighted subtraction. Excel template was developed with advanced silicon suppliers and open in a website.