Crystallization of Amorphous Silicon Films Annealed by Line Shape Excimer Laser Beam

Abstract

Abstract: The line shape excimer laser beam has been widely used in the industrial production of poly-silicon films. The large size amorphous silicon film prepared by plasma enhanced chemical vapor deposition is annealed by the line shape excimer laser beam output from the self-developed laser annealing equipment. The effects of energy density and irradiation times of the line shape laser beam on the crystallization of amorphous silicon films are researched. The crystallization volume fraction and the uniformity of the acquired large size poly-silicon film are discussed. The experimental results show that the crystallization threshold of the amorphous silicon film is 194 mJ•cm-2. The crystallization volume fraction increases with a linear factor of 0.3 first, and then decreases slowly. When the energy density is 432 mJ•cm-2, the crystallization degree reaches its peak. The crystallization volume fraction keeps stable when the number of irradiation is above 20. The crystallization volume fraction of the acquired large size poly-silicon film is 92.26% with the relative standard deviation of 1.56% in the right region under the overlap ratio of 93.7%, which are slightly better than the left region. This work gives references to the research of amorphous silicon film crystallization annealed by line shape laser beam and the nationalization of the line beam excimer laser annealing equipment.

Key words: thin films, poly-silicon, excimer laser annealing, energy density, overlap ratio, line shape laser beam

Yin Guangyue1,2,3, You Libing1,3*, Chen Xing1,2,3, Shao Jingzhen1,3, Chen Liang1,2,3, Wang Qingsheng1,3, Fang Xiaodong1,2,3. Crystallization of Amorphous Silicon Films Annealed by Line Shape Excimer Laser Beam[J]. Chinese Journal of Quantum Electronics.

References

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