The current status in the silicon crystal growth technology for solar cells

(Received January 17, 2014)(Revised April 8, 2014)(Accepted April 14, 2014)Abstract Three kinds of crystalline silicon have been used for the solar cell grade. First of all, single crystalline silicon isthe main subject to enhance the production yield. Most of the efforts are focused on the control of the melt-crystalinterface shape affected by the crystal-crucible rotation rate. The main subject in the multi-crystalline silicon ingot is thecontamination control. Faster Ar gas flow above the melt surface will lower the carbon contamination in the crystal. Andalso, twin boundary electrically inactive is found to be more effective than grain boundary for the improvement of theMCLT. In the case of mono-like silicon material, propagation of the multi-crystalline silicon growing from the inner sidecrucible is the problem lowering the portion of the single crystalline part at the center of the ingot. Crystal growingapparatus giving higher cooling rate at the bottom and lower cooling rate at the side crucible was suggested as theoptimum solution obtaining higher quality of the mono-like silicon ingot. Proper application of the seeds at the bottom ofthe crucible would be one of the solutions.Key wordsCrystalline silicon solar cell, Single crystalline Si, Multi-crystalline Si, High efficiency, Mono-like Si