High Quality a-SiO:H Films and Their Application to a-Si Solar Cells

Abstract

Hydrogenated amorphous silicon oxide (a-SiO:H) films were prepared by rf glow discharge decomposition of SiH4, C02 and H2 gas mixture. These films showed better properties than a-SiC:H films. By applying the a-SiO:H to the player, we attained an efficiency of 12.5% for 1cm 2 single junction solar cells and a total-area efficiency of 10.1% for 30cm x 40cm tandem submodules.

Comparison of silicon oxide and silicon carbide absorber materials in silicon thin-film solar cells

“…Unlike our remaining results conductivity measurements seem to indicate better performance of samples prepared with CO 2 than with CH 4 in agreement with Haga et al [5] and Fujikake et al [6]. One explanation could be an unintentional doping effect especially in the 65302-p5 EPJ Photovoltaics silicon oxide films.…”

“…Although CO 2 contains carbon almost no carbon is incorporated into the layer in agreement with previous results [6]. As can be seen in Figure 3 oxygen is incorporated more easily into the network since higher oxygen than carbon concentrations are reached at equivalent flows of CO 2 and CH 4 .…”

“…Yet it is unclear which amorphous silicon alloy is preferable as top cell absorber. Haga et al [5] and Fujikake et al [6] observed the photoconductivity of aSiO:H to be higher by orders of magnitude compared to a-SiC:H at similar optical bandgaps. However photoconductivity does not always relate to cell performance if the absorber material is not truly intrinsic [14].…”

“…Consequently high bandgap amorphous silicon alloys containing carbon, oxygen or both are considered as absorber materials for the top cell. Their single layer properties have been studied for some time [2][3][4][5][6][7][8] and recently their applicability in single and multijunction cells has been confirmed [9][10][11][12][13]]. Yet it is unclear which amorphous silicon alloy is preferable as top cell absorber.…”

The role of buffer layer between TCO and p-layer in improving series resistance and carrier recombination of a-Si:H solar cells

“…A number of papers have been published on the development of p-type hydrogenated amorphous silicon oxide (a-SiO x :H) films and their application in fabrication of single and multi-junction solar cells [1][2][3]. In spite of considerable advances in the quality of amorphous material, the recombination at the TCO/p-layer interface affects the solar cell efficiency [4].…”