Temperature Dependence of Si-Based Thin-Film Solar Cells Fabricated on Amorphous to Microcrystalline Silicon Transition Phase

Abstract

The temperature dependence of silicon (Si)-based thin-film single-junction solar cells, whose intrinsic absorbers were fabricated on the transition phase between hydrogenated amorphous silicon (a-Si:H) to hydrogenated microcrystalline silicon (mc-Si:H), was investigated. By varying the hydrogen dilution ratio, wide-band-gap protocrystalline silicon (pc-Si:H) and mc-Si:H absorber layers were obtained. Photo-current density-voltage (Photo-J-V) characteristics were measured under AM1.5 illumination at ambient temperatures in the range of 25 -75 C. We found that the solar cells with pc-Si:H, which exists just below the a-Si:H to mc-Si:H transition boundary, showed the lowest temperature coefficient (TC) for conversion efficiency () and open-circuit voltage (V oc ), while the solar cells fabricated at the onset of the a-Si:H to mc-Si:H phase transition exhibited a relatively high TC for and V oc . Experimental results indicated that pc-Si:H is a promising material for the absorber layer of the single junction or the top cell of tandem solar cells that operate in high temperature regions.

Performance of Si-based PV rooftop systems operated under distinct four seasons

“…10(b) shows the results for the 3-kW p c-Si PV generators mounted with the fixed tilt angle of 10 and 35 . In general, the outdoor electricity-generation of the PV generators is affected by the module temperature, planeof-array irradiance [26], spectral distribution [26,27], temperature coefficient [28], transmittance of aged PV glasses [29] and aged EVA films [30], dust effect [31e33], and partial shading effect on PV modules [34,35]. The superstrate-type a-Si:H single-junction PV modules may be free from the effect of the aged EVA films, however it is also significantly impacted by the Staebler-Wronski effect [27,36].…”

Development of amorphous silicon-based thin-film solar cells with low-temperature coefficient

“…6. Regarding our previous study, the TC value for η of µc-Si:H single-junction solar cells was found in the range of -0.45 to -0.66%/ o C [9], whereas TC for η of pc-Si:H single-junction solar cells was about -0.20 to -0.30%/ o C [10][11]. We found that the temperature dependence of double-junction solar cells showed a similar behavior to single-junction solar cells.…”

“…In case of pc-SiO:H solar cells, the carbon dioxide concentration (CC=CO 2 /[CO 2 +SiH 4 ]) ratio was kept constant at 0.07 while SC was varied. More details for the fabrication of pc-Si:H and pc-SiO:H single-junction solar cells were explained in elsewhere [10,16]. Some deposition conditions in each layer are shown in Table 1.…”

“…Recently, it has been reported by our group that the hydrogenated protocrystalline silicon (pc-Si:H) single-junction solar cell showed a good temperature dependence among Si-based thin-film solar cells [9][10][11]. Moreover, other wide bandgap materials such as hydrogenated protocrystalline silicon oxide (pc-SiO:H) single-junction solar cell was also fabricated by our group.…”

“…Since, the temperature dependence of pc-Si:H single-junction solar cells have been investigated by our group [9][10][11]. It was found that, V oc of the solar cells almost linearly decreased while J sc progressively increased with the increase in T. In the case of FF, it also decreased with the increase in T. The drop in V oc and FF led to the reduction of η with increasing temperature.…”