A Convenient and Effective Method to Deposit Low-Defect-Density nc-Si:H Thin Film by PECVD

Abstract

Hydrogenated nanocrystalline silicon (nc-Si:H) thin film has received a great deal of attention as a promising material for flat panel display transistors, solar cells, etc. However, the multiphase structure of nc-Si:H leads to many defects. One of the major challenges is how to reduce the defects conveniently. In this work, we developed a simple and effective method to deposit low-defect-density nc-Si:H thin film. This method is simply by tuning the deposition pressure in a high-pressure range in plasma-enhanced chemical vapor deposition (PECVD) process. Microstructures of the nc-Si:H were characterized by Raman, AFM, and SEM. Furthermore, we focused on the defect density which was the key characteristic for photovoltaic materials and achieved the defect density of 3.766 × 1016 cm−3. This defect density is lower than that of previous studies on the fabrication of low-defect-density nc-Si:H by other complex methods in PECVD process. The minority carrier lifetime of nc-Si:H is thus greatly improved. Moreover, we demonstrated the mechanism about the effect of deposition pressure on the ion bombardment and proved that the defect density is the key characteristic for nc-Si:H photovoltaic material.Electronic supplementary materialThe online version of this article (10.1186/s11671-018-2641-z) contains supplementary material, which is available to authorized users.

Electrically conductive silicon oxycarbide thin films prepared from preceramic polymers

“…Until now, there is no direct correlation found on how the defect density responds to the decreasing thickness of a material. [69][70][71] In comparison with the previous work of Rosenburg on the SiOC monolithic sample, 8 the calculated L a and L D of the SiOC film were of similar magnitude; the dispersed particles giving the largest L a and L D values. The L D calculation followed the assumption that point defects are present on the phases and that the radius around the defect (r A ) where D band scattering takes place is equal to 3.1 nm.…”

“…Conversely, the defect density behaved inversely proportional to the heat-treatment temperature with the C17-1400 thin film sample showing a high degree of steepness on its slope. Until now, there is no direct correlation found on how the defect density responds to the decreasing thickness of a material [69][70][71] . In comparison with the previous work of Rosenburg on the SiOC monolithic sample 8 , the calculated L a and L D of the SiOC film were of similar magnitude; the dispersed particles giving the largest L a and L D values.…”

A lead-free halide hybrid perovskite (TMHD)BiCl5 for ultraviolet photodetection

“…n trap was determined to be 8.2 × 10 10 cm −3 . This value is even lower than that of polycrystalline Si (10 13 to 10 14 cm −3 ) 32 and CdTe (10 11 –10 13 cm −3 ). 33 At a higher bias, the current showed a quadratic dependence ( I ∝ V 2 ).…”

Quasi‐Single Crystalline Cuprous Oxide Wafers via Stress‐Assisted Thermal Oxidation for Optoelectronic Devices

“…Figure 4c shows that the <110>‐textured Cu 2 O prepared by the BSATO method exhibits a much lower n trap of 2.8 × 10 11 cm −3 , compared with the control sample with a n trap of 5.60 × 10 11 cm −3 (Figure S13, Supporting Information). It should be noted that the n trap of these BSATO Cu 2 O quasi‐single crystals is approximately two orders of magnitude lower than that of the lead halide perovskite microcrystalline thin film (10 13 cm −3 ), [ 40 ] and approximately two or three orders of magnitude lower than that of the commercial semiconductors, including Si ( n trap = 10 13 –10 14 cm −3 ), [ 41 ] CdTe ( n trap = 10 11 –10 13 cm −3 ), [ 3 ] and CIGS ( n trap ≈10 13 cm −3 ). [ 42 ]…”