High rate PECVD of low defect density a-Si:H on large areas

Conference · Tue Jul 01 04:00:00 EDT 1997

OSTI ID:20085535

Roehlecke, S; Steinke, O; Schade, K; Stahr, F; Albert, M; Deltschew, R; Kottwitz, A; Carius, R

Industrial production of amorphous silicon solar cells, photoreceptors and several opto-electronic devices requires large area, high-deposition-rate plasma reactors and deposition processes. Non-uniformity of the film thickness and particle generation at high power densities as well as the deposition rate are found to be important limiting factors in large area PECVD. The deposition was performed in a capacitively-coupled coaxial diode rf glow discharge with large areas (1,000 cm{sup 2} and 2,000 cm{sup 2}) at 13.56 MHz and 27.12 MHz. The authors studied the particle generation in the plasma reactor over a wide range of silane concentration (20% to 100%) in the SiH{sub 4}/He mixture. They will present the opto-electronic properties of a-Si:H films and the influence of the substrate bias. The films are characterized by dark- and photoconductivity and by PDS. It was confirmed through this study that helium dilution is effective in the suppression of powder growth for high-rate deposition up to 18 {micro}m/hr. Special attention was paid to the optimization of reactor design and plasma conditions for the deposition of low density of states a-Si:H ({approximately}10{sup 16} cm{sup {minus}3}) at deposition rates of up to 18 {micro}m/hr. Dark conductivity was 10{sup {minus}9} S/cm and photoconductivity was about 5{center_dot}10{sup {minus}4} S/cm.

• Research Organization: FAP GmbH Dresden (DE)
• OSTI ID: 20085535
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
42 ENGINEERING
CHEMICAL REACTORS
CHEMICAL VAPOR DEPOSITION
CRYSTAL DEFECTS
ELECTRICAL PROPERTIES
OPTICAL PROPERTIES
SEMICONDUCTOR DEVICES
SILICON SOLAR CELLS