[17p-B2-1~9] 15.7 Crystal characterization, impurities and crystal defects

3:15 PM - 3:30 PM JST(6:15 AM - 6:30 AM UTC)

[17p-B2-9] Measurement of carbon concentration in silicon crystal/ 2-nd generation
(28) Solution of middle and inner phonon band problems in infrared absorption (1)

〇Naohisa Inoue¹, Shuichi Okuda¹, Shuichi Kawamata¹ (1.Osaka Metropolitan Univ. Radiation Research center)

Keywords:

silicon crystal,carbon concentration,infrared absorption

Around 2005 power device took attention. We developed 2nd gen IR. There are four key techniques (1) prepare carbon-free reference, (2) estimate instrumental DL and (3) solve phonon problem. Basic part was transferred to world’s leading Si suppliers. There are three phonon bands (i) outer at 575 and 625, (ii) middle at 612 and (iii) inner at 600 and 608 cm-1. Outer bands are distinct above 1015/cm3, separate from carbon band. Middle baseline 590 - 618 cm-1 solves problem. Middle band becomes comparable to carbon band around 5x1014/cm3. Both bands overlap, but is nearly 0 at carbon peak. Middle baseline is solution also. Measurement of 2-3x1014/cm3 was established. Inner bands are comparable and close to carbon band around 1014/cm3. Short baseline 600 - 610 cm-1 works well at RT. (3a) Low temp. IR is widely used since ‘70s. We found it separates inner bands from carbon at liq. N temp. Measurement of 1013/cm3 was demonstrated. (4) Measurement of poly-Si of 1014/cm3 was established.