[10p-N203-1~9] 15.7 Crystal characterization, impurities and crystal defects

[10p-N203-9] Measurement of carbon concentration in silicon crystal
(23) Instrumental detection limit and spectral detection limit of infrared absorption

〇Naohisa Inoue¹, Shuichi Okuda¹, Shuichi Kawamata¹ (1.Osaka Pref. Univ.)

Keywords:silicon crystal, carbon concentration, infrared absorption

Second generation IR measurement technique of carbon concentration in Si down to 1x10¹³/cm³ has been established under the collaboration with IR researchers and Si companies in the world. We (NTT and NBS) started the collaboration with ASTM in 1979. To include this already and widely used technique in SEMI standard, interrupted revision was restarted in 2019. The definition, practice and evidence of the detection limit in the standard are not enough. In the last meeting, we proposed the instrumental detection limit (IDL) and spectral detection limit (SDL), based on the discussion with IR professionals and SEMI Standard experts. Here they are discussed and tentative examples of IDL below 1x10¹⁴/cm³ and SDL about 3x10¹³/cm³ are shown. Two other procedures were proposed then also: 4cm^-1 resolution, easier and more sensitive and applicable to 1 mm thickness. Background fitting function, basic procedure of spectroscopic analysis and included already in JEIDA N Standard, instead of baseline.