Optimization of saturation current density of PECVD SiN coated phosphorus diffused emitters using neural network modeling

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Journal of Electronic Materials

DOI:https://doi.org/10.1007/s11664-996-0036-x· OSTI ID:420694

Cai, L; Han, S; May, G; Kamra, S; Krygowski, T; Rohatgi, A ^[1]

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1. Georgia Inst. of Technology, Atlanta, GA (United States)

Emitter surface passivation by low temperature plasma enhanced chemical vapor deposition (PECVD) silicon nitride is investigated and optimized in this paper. We have found that the saturation current density of a 90{+-}10 {Omega}/sq phosphorus diffused emitter with N{sub s} 3x10{sup 19} and X{sub j} = 0.3{mu}m can be lowered by a factor of eight by appropriate PECVD silicon nitride deposition and photo-assisted anneal. PECVD silicon nitride deposition alone reduces the emitter saturation density (J{sub oe}) by about a factor of two to three, and a subsequent photoanneal at temperatures >=350{degree}C reduces J{sub oe} by another factor of three. In spite of the larger flat band shift for direct PECVD silicon nitride coating, the silicon nitride induced surface passivation is found to be about a factor of two inferior to the thermal oxide plus PECVD silicon nitride passivation due to higher interface state density at the SiN/SiO{sub 2} interface compared to SiO{sub 2}/Si interface. A combination of statistical experimental design and neural network modeling is used to show quantitatively that lower radio frequency power, higher substrate temperature, and higher reactor pressure during the PECVD deposition can reduce the J{sub oe} of the silicon nitride coated emitter. 29 refs., 6 figs., 1 tab.

• Sponsoring Organization: USDOE
• OSTI ID: 420694
• Journal Information: Journal of Electronic Materials, Journal Name: Journal of Electronic Materials Journal Issue: 11 Vol. 25; ISSN JECMA5; ISSN 0361-5235
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
42 ENGINEERING
99 GENERAL AND MISCELLANEOUS
ANNEALING
CHEMICAL VAPOR DEPOSITION
COATINGS
CURRENT DENSITY
DEPOSITION
MATHEMATICAL MODELS
NEURAL NETWORKS
OPTIMIZATION
PASSIVATION
PHOSPHORUS
PHOTOCHEMICAL REACTIONS
PLASMA
SEMICONDUCTOR DEVICES
SILICON NITRIDES
SURFACES