The C-2 radical density was measured in a low-pressure, radio frequency (rf
), inductively coupled plasma (ICP) employing a CH3OH/H-2/H2O mixture. Meas
urement was carried out under the conditions where predominantly diamond ca
n be formed. At the typical growth conditions for the low-pressure, rf ICP
reactor used for diamond formation, the C-2 radical density in the ICP regi
on was of the order of 10(13) cm(-3). The correlation between the C-2 radic
al density and the quality of diamond films was investigated. (C) 2001 Else
vier Science B.V. All rights reserved.