Reducing Reflectance on Silicon Solar Cells Surfaces by Controlling X-Y Translation Table Speeds of Pulsed Nd:YAG Laser System

Surface texturing is very important in silicon solar cells fabrication in order to enhance light trapping by reducing surface reflectance. Basically, silicon solar cells surfaces will be etched by chemical solution either anisotropic etched or isotropic etched which are known as conventional methods. The chemicals that have been used for this conventional method includes alcohol, acids, potassium hydroxide and addictive chemical like surfactant. Even though the texture surfaces created by chemical etched can reduce the reflectance, this technique is not environmental friendly. This technique could only be applied on monocrystalline silicon, but not for the multicrystalline silicon because of the presence of high selectivity of etching along specific directions and multiple crystallographic grain orientation. Moreover, the chemicals waste could harmed and give pollution to the environment. In this paper, new technique has been used to texture the silicon solar cells surfaces. The new texturing technique proposed in this paper is pulsed Nd:YAG laser. By using pulsed Nd:YAG laser, it can texture silicon solar cells surfaces and reduce the reflectance. Pulsed Nd:YAG laser also can working independently on any types of silicon surfaces. However, the groove lines of laser texturing depending on X-Y translation table that connected to pulsed Nd:YAG laser system. This paper explained the effect of various X-Y translation table settings of pulsed Nd:YAG laser to texturing silicon solar cells surfaces in order to reduce the reflectance percentage. As a result, pulsed Nd:YAG laser texturing on silicon solar cells surfaces in this paper shown the reflectance below than 5% which is very significant in order to increase absorption of incident solar radiation.