In this work, hydrogenated microcrystalline silicon (μc-Si:H) films deposited through very high frequency plasma enhanced chemical vapor deposition (VHF- PECVD) were investigated. First of all deposition parameters such as total pressure, substrate temperature, silane concentration, distance between electrodes, total gas flow rate, and plasma power were varied to investigate their effects on the properties of the intrinsic μc-Si:H absorber layers. we found that at a high growth rate of 7.3 A/s, a μc-Si:H thin film with optimized properties of 64 % crystalline ratio and 1.72 x10-6S/cm dark conductivity was obtained under a power density of 177 mW/cm2, substrate temperature of 200 oC, silane concentration of 4 % and total pressure of 1.5Torr. Furthermore, effects of doping ratio and thickness on the properties of both p-type and n-type μc-Si:H doped layers were explored. The results showed that a20nm thick p-type μc-Si:H layer which possessed high dark conductivity of 1.7x 10-1 S/cm was achieved using a trimethylboron/silane doping ration of 0.2 %, and a substrate temperature of 180 oC. On the other hand, a 25 nm thick n-type μc-Si:H layer with3.7 S/cm dark conductivity was established under a tert-butylphosphine/silane ratio of 0.5 %. Finally, by combining the optimized conditions for each layer, we tried to make a μc-Si H thin film solar cell using the standard Asahi U glass. The result showed a short circuit current density of 10.45mA/cm2, open-circuit voltage of 0.4 V, fill factor of 44.6 %, and efficiency of 1.83 %.

In this work, hydrogenated microcrystalline silicon (μc-Si:H) films deposited through very high frequency plasma enhanced chemical vapor deposition (VHF- PECVD) were investigated. First of all deposition parameters such as total pressure, substrate temperature, silane concentration, distance between electrodes, total gas flow rate, and plasma power were varied to investigate their effects on the properties of the intrinsic μc-Si:H absorber layers. we found that at a high growth rate of 7.3 A/s, a μc-Si:H thin film with optimized properties of 64 % crystalline ratio and 1.72 x10-6S/cm dark conductivity was obtained under a power density of 177 mW/cm2, substrate temperature of 200 oC, silane concentration of 4 % and total pressure of 1.5Torr. Furthermore, effects of doping ratio and thickness on the properties of both p-type and n-type μc-Si:H doped layers were explored. The results showed that a20nm thick p-type μc-Si:H layer which possessed high dark conductivity of 1.7x 10-1 S/cm was achieved using a trimethylboron/silane doping ration of 0.2 %, and a substrate temperature of 180 oC. On the other hand, a 25 nm thick n-type μc-Si:H layer with3.7 S/cm dark conductivity was established under a tert-butylphosphine/silane ratio of 0.5 %. Finally, by combining the optimized conditions for each layer, we tried to make a μc-Si H thin film solar cell using the standard Asahi U glass. The result showed a short circuit current density of 10.45mA/cm2, open-circuit voltage of 0.4 V, fill factor of 44.6 %, and efficiency of 1.83 %.

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