Material properties of microcrystalline silicon for solar cell application

Structural analysis of CIGS film prepared by chemical spray deposition

“…Compared with CH-fractions of 0.9e0.92 for SS CIGS films, those for SP CIGS films are much low. For improvement of film quality of SP CIGS films, higher substrate temperature may be desirable as it is reported for the growth of CuInS 2 [17] and CuInSe 2 [23]. However, we had some difficulties related with growth rate in growing SP CIGS films at higher temperatures.…”

“…It is also noted that the frequency of A1 mode for SP CIGS film (x ¼ 0) is measured to be 168.5 cm À1 , which is smaller than 172 cm À1 [12], 173 cm À1 [13], 174 cm À1 [14,15], 175 cm À1 [16] reported by others. When the substrate temperature is low during spray of CuInS 2 [17] or Cu 2 ZnSnS 4 [18], the as-deposited film shows A1 peak at lower frequency. But frequency of A1 mode for single crystal is restored after thermal annealing [17,18].…”

“…When the substrate temperature is low during spray of CuInS 2 [17] or Cu 2 ZnSnS 4 [18], the as-deposited film shows A1 peak at lower frequency. But frequency of A1 mode for single crystal is restored after thermal annealing [17,18]. Comparing shapes of A1 peaks, SP CIGS shows somewhat asymmetric shape, and there seems to be a tail at higher frequency side.…”

H2 plasma treatment at the p/i interface of a hydrogenated amorphous Si absorption layer for high‐performance Si thin film solar cells

“…The general deposition conditions for the a-Si:H films were as follows: H 2 /SiH 4 ratio: 15, deposition temperature: 180 C, process pressure: 5 Torr, and electrode gap: 10 mm. These values are very close to those of the optimized a-Si:H and mc-Si:H films as reported in the previous study [7,17]. We optimized the RF power for the deposition of a-Si:H films by evaluating the material properties of the films with Raman spectroscopy, Fourier-transform infrared spectroscopy, and optical transmittance measurements.…”

“…The following fabrication method of mc-Si:H films by using PECVD, to make their material properties suitable for use in high-efficiency tandem cells, was recently reported by our group: mc-Si:H films are prepared at high pressure with a narrow electrode gap and high atomic hydrogen density for low ion damage during the PECVD process [7]. In our experiments, these mc-Si:H single-junction solar cells showed high stability without significant loss in solar cell performance on air exposure for 6 months and subsequent illumination for over 300 h. In addition, when these optimized mc-Si:H films were combined in a-Si:H/mc-Si:H tandem modules (200 Â 200 mm 2 ), high efficiencies (h) of~12% (initial) and~10% (stabilized) were obtained.…”