Pulsed Supermagnetron Plasma CVD of a-CN_x:H Electron-Transport Films for Au/a-CN_x:H/p-Si Photovoltaic Cells

Haruhisa Kinoshita, Hiroyuki Suzuki

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DOI: 10.4236/jmp.2011.25049                

Abstract

Hydrogenated amorphous carbon nitride (a-CN_x:H) films were formed on p-Si wafers set on a lower elec-trode by pulsed supermagnetron plasma CVD using i-C₄H₁₀ and N₂ gases. Lower electrode RF power (LORF) of 13.56 MHz (50 - 800 W) was modulated by a 2.5-kHz pulse at a duty ratio of 12.5%, and upper electrode RF power (UPRF) of 50 - 400 W was supplied continuously. The optical band gap decreased with an increase in LORF at each UPRF. The open circuit voltage of Au/a-CN_x:H/p-Si photovoltaic cells (a-CN_x:H film thickness: 25 nm) was about 200 mV for each cell, and the short circuit current density and energy conversion efficiency increased with LORF for each UPRF. The highest energy conversion efficiency of 0.81% was obtained at UPRF/LORF of 200/800 W.

Keywords

a-CN_x:H film, Supermagnetron Plasma, Pulsed Plasma, CVD, Photovoltaic Cell

Conflicts of Interest

The authors declare no conflicts of interest.

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