Summary

Chapter 4 Conclusions and Future Work

4.1 Conclusions

Predicting the improve the efficiency in this paper, we succeeded in improving two of the key factors to texture structure and electroless plating.

The objectives of this thesis are to study roughness of the surface and the anti-reflection layer technique for single crystal silicon solar cell. The design of solar cell surface roughness texture is a necessary step. For incident light get multiple reflections, various applications, enlarging light access area and increase the possibility for light absorbing.

The p-type silicon wafer as a substrate, phosphorus diffusion 30 minutes at high temperature furnace diffusion process to make single-crystal silicon solar cell p-n junction. This sample the ISC =133.928 mA, VOC =0.500 V ,and evaluated fill factor (FF)

=41.499%, efficiency (η) =7.282%. Phosphorus diffusion 40 minutes at high temperature furnace diffusion, this sample the ISC =143.449 mA, VOC =0.550 V ,and evaluated fill factor (FF) =39.411 %, efficiency (η) =8.148%.

Contrary pyramid sink structure is the best light sealed for safekeeping design and extensively using at high efficiency single crystal solar cell fabrication.

P-type(100)silicon is to be the base and to go on anisotropy wet etching in KOH solution that will get contrary Pyramid sink structure. To study KOH etching rates in the heating temperature 75 ~ 80 ℃ and surface textured 20 minutes. The ISC =43.873 mA, VOC =0.45 V ,and evaluated fill factor (FF) =41.287%, efficiency (η) =8.151%. Surface textured 30 minutes, the ISC =39.519 mA, VOC =0.520 V ,and evaluated fill factor (FF) =47.915%, efficiency (η) =9.847 %.

We have developed a simple method using complexing agent to synthesize Ni/Cu nanoparticles in ambient condition. the ISC =45.459 mA, VOC =0.540V ,and evaluated fill factor (FF) =56.248%, efficiency (η) =13.808 %.

Finally, we discussed the result what we got to find out the rule: the relationship between the chemical plating, , we can get a lower efficiency . Because the shunt resistance Rsh should be as high as possible to avoid leakage of carriers back across the junction. So we have to do to improve, we could get a better efficiency (η).

4.2 Future Work

Although in the industry use of AR coating or etching of various ways to change the reflectivity of incident light to enhance the conversion of solar, but the paper chemical plating process, simplicity and low cost, also easy to control coating thickness.

In the follow-up of the future, all the lack of response to future energy development and the next generation of energy, conversion efficiency of solar cells there is still much room for progress, I believe the future of the people for the development of alternative energy, solar cells must be the best choice.

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