Recent advances in hot-wire CVD R&D at NREL: From 18% silicon heterojunction cells to silicon epitaxy at glass-compatible temperatures

Kirchhoff's generalised law applied to amorphous silicon/crystalline silicon heterostructures

“…The simulation software SC-Simul [5,6] The programme determines all the physical properties of interest, e.g., the quasi-Fermi levels or the free electron and hole densities, the electrostatic potential and other properties like recombination rates. The input parameters are the semiconductor properties of the different layers with which a structure is built, like the band gap E g , effective densities of states in the band, free carrier mobilities, electron affinity, capture coefficients for defect states and parameters for defect densities and distributions.…”

“…Here, both the wafer pre-treatment prior to the amorphous silicon deposition and the a-Si:H deposition itself, typically by plasma enhanced chemical vapour deposition (PECVD), are important, e.g. [3][4][5][6][7].…”

Epitaxial growth of silicon and germanium on (100)-oriented crystalline substrates by RF PECVD at 175 °C

“…Coupled PECVD [8] as well as by Hot Wire CVD [9]. In most of these cases, except in reference [6], the substrate was kept at a relatively high temperature to favor the epitaxial growth (T 700 • C).…”

Simulation and fabrication of heterojunction silicon solar cells from numerical computer and hot‐wire CVD

“…2,3 The hot-wire chemical vapor deposition (HWCVD) technique has attracted much less attention to fabricate Si HJ solar cells. [4][5][6] However, some technological advantages could be argued in terms of deposition rate, gas decomposition, and no ion bombardment. To our knowledge, the best HJ solar cell with an efficiency of 18Á2% by HWCVD has been fabricated by the group at the National Renewable Energy Laboratory.…”

“…To our knowledge, the best HJ solar cell with an efficiency of 18Á2% by HWCVD has been fabricated by the group at the National Renewable Energy Laboratory. 4 The emitter layer in the HJ solar cell is usually highly doped to reduce the series resistance and very thin to minimize the recombination of photogenerated carriers in the layer. In addition, it has been reported that the interface condition, such as band offset and interface defects, significantly affects the carrier transport and photovoltaic properties of these solar cells.…”