Low-damage surface smoothing of laser crystallized polycrystalline silicon using gas cluster ion beam

✍ Scribed by H. Tokioka; H. Yamarin; T. Fujino; M. Inoue; T. Seki; J. Matsuo

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 424 KB
• Volume: 257
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2007.01.269

✦ Synopsis

Surface smoothing of laser crystallized polycrystalline silicon (poly-Si) films using gas cluster ion beam (GCIB) technology has been studied. It is found that both SF6-GCIB and O2-GCIB decrease the height of hillocks and reduce the surface roughness of the irradiated films. The mean surface roughness value of poly-Si films was reduced from 10.8 nm to 2.8 nm by SF6-GCIB irradiation at 80°. Ultraviolet reflectance measurement reveals that GCIB irradiation causes damage near-surface of the poly-Si films. Formation of the damage, however, can be suppressed by using GCIB irradiation at high incident angle. Effect of GCIB irradiation in a metal-insulator-semiconductor (MIS) capacitor has also been investigated. The capacitance-voltage curves of MIS capacitor with SF6-GCIB irradiation are distorted. On the contrary, the distortion is reduced by O2-GCIB irradiation at 80, which suggests that electrical-activated damage of the films can be decreased by using O2-GCIB irradiation.