Effect of Crystallinity on the Electrical Characteristics of Poly-Si Tunneling FETs via Green Nanosecond Laser Crystallization

This letter reports the fabrication of polycrystalline silicon (poly-Si) tunneling field effect transistors (Tunneling FETs) using green nanosecond laser crystallization (GLC). During the GLC process, the Si is full-melted by laser scanning, hence the recrystallized poly-Si thin films with grain size as large as $1.2~\mu \text{m}$ are attained. This makes it possible to fabricate tunneling FET with high-quali ty poly-Si thin films. Compare with the tunneling FETs fabricated by solid phase crystallization (SPC), the ones via GLC show better subthreshold swing (S.S) of 418 mV/dec. and larger on/off ratio of $6.02 \times 10^{5}$ . Moreover, the activation energy curve is also presented to further demonstrate the con nection between device performance and crystallinity of poly-Si thin films.