Correlation of the growth rate for selective epitaxial growth of silicon and oxide thickness and oxide coverage in a reduced pressure chemical vapor deposition pancake reactor
Journal
Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
Journal Volume
26
Journal Issue
5
Pages
1712-1717
Date Issued
2008
Author(s)
Lee, K.-Y.
Abstract
The selective epitaxial growth (SEG) rate of silicon for wafers with various oxide coverages (OCs) (the ratio of oxide area to silicon area on a silicon wafer) and oxide thicknesses, ranging from 0% to 90% and 0to500nm, respectively, in a rf heated cold-wall reduced-pressure chemical vapor deposition (RPCVD) pancake reactor, using the SiH2Cl2–HCl–H2 gas system, was investigated at a chamber pressure of 40Torr and a temperature of 970°C. The highest growth rate is about 175nm∕min, occurred at the oxide coverage of 90% and oxide thickness of 200nm; the lowest growth rate is about 112nm∕min, occurred at the oxide coverage of 30% and oxide thickness of 500nm. The growth rate of a control sample (a bare silicon wafer) is 110nm∕min. According to these data, a semiempirical expression for the SEG rate of undoped wafers in an RPCVD pancake reactor system is developed. The growth rate is exponentially dependent on the oxide coverage and a function of oxide thickness. This expression is suitable for the in situ p-type doped wafer with 60% OC and the boron concentration of 1.0×1017cm−3 as well.
Type
journal article