Citation: |
Yehua Tang, Yuchao Wang, Chunlan Zhou, Ke-Fan Wang. Structure and electrical properties of polysilicon films doped with ammonium tetraborate tetrahydrate[J]. Journal of Semiconductors, 2024, 45(10): 102302. doi: 10.1088/1674-4926/24030032
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Y H Tang, Y C Wang, C L Zhou, and K F Wang, Structure and electrical properties of polysilicon films doped with ammonium tetraborate tetrahydrate[J]. J. Semicond., 2024, 45(10), 102302 doi: 10.1088/1674-4926/24030032
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Structure and electrical properties of polysilicon films doped with ammonium tetraborate tetrahydrate
DOI: 10.1088/1674-4926/24030032
CSTR: 32376.14.1674-4926.24030032
More Information-
Abstract
Here, p-type polysilicon films are fabricated by ex-situ doping method with ammonium tetraborate tetrahydrate (ATT) as the boron source, named ATT-pPoly. The effects of ATT on the properties of polysilicon films are comprehensively analyzed. The Raman spectra reveal that the ATT-pPoly film is composed of grain boundary and crystalline regions. The preferred orientation is the (111) direction. The grain size increases from 16−23 nm to 21−47 nm, by ~70% on average. Comparing with other reported films, Hall measurements reveal that the ATT-pPoly film has a higher carrier concentration (>1020 cm−3) and higher carrier mobility (>30 cm2/(V·s)). The superior properties of the ATT-pPoly film are attributed to the heavy doping and improved grain size. Heavy doping property is proved by the mean sheet resistance (Rsheet,m) and distribution profile. The Rsheet,m decreases by more than 30%, and it can be further decreased by 90% if the annealing temperature or duration is increased. The boron concentration of ATT-pPoly film annealed at 950 °C for 45 min is ~3 × 1020 cm−3, and the distribution is nearly the same, except near the surface. Besides, the standard deviation coefficient (σ) of Rsheet,m is less than 5.0%, which verifies the excellent uniformity of ATT-pPoly film. -
References
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