The recrystallization characteristics of polycrystalline silicon (poly-Si) films amorphized by germanium ion (Ge+) implantation on a SiO2 layer are studied by TEM analysis, and the possibility of enlarging the final grain size is investigated. Also, the characteristics of Ge+ implanted films with phosphorus doping are reported and discussed. The nucleation and growth rates of undoped Ge+ implanted films are lower and higher, respectively, than those of silicon ion (Si+) implanted films, so that the former films achieve grain sizes about 2-3 times larger than the latter films, depending on annealing temperature. Phosphorus doping in Ge+ implanted films effectively enhances the grain size, because of the retardation of random nucleation and the enhancement of grain growth. An average grain size of 12 μm is obtained in doped Ge+ implanted films with a phosphorus concentration of 1 × 1020 ions/cm3 after annealing at 650°C for 5 h, which is about four times larger than that in undoped Ge+ implanted films.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry