M. Yoshimoto et al., ELECTRICAL-PROPERTIES OF SILICON-NITRIDE FILMS PREPARED BY PHOTO-ASSISTED CHEMICAL-VAPOR-DEPOSITION UNDER CONTROLLED DECOMPOSITION OF AMMONIA, JPN J A P 1, 32(12B), 1993, pp. 6132-6136
Silicon nitride (SiN(x)) films have been deposited at lower substrate
temperatures (less-than-or-equal-to 500-degrees-C) by direct (without
Hg-sensitization) photo-chemical vapor deposition (photo-CVD) with a l
ow-pressure Hg lamp using SiH4 and NH3. The resistivity was as high as
5 X 10(16) OMEGAcm. The minimum value of interface-trap density in Al
/SiN(x)/Si metal-nitride-semiconductor (MNS) diodes was estimated to b
e 9 x 10(10) cm-2 eV-1 by a quasi-static capacitance-voltage measureme
nt. In contrast to conventional plasma CVD of SiN(x), the formation of
intermediate species is controlled by the decomposition of NH3 which
is decomposed to a lesser extent in a plasma process, based on analyse
s of film structures and transient mass spectroscopy, This effect caus
es the properties of SiN(x) to not change in a wide range of NH3/SiH4
gas composition.