GaAsP/Si dual-junction solar cells grown by MBE and MOCVD

GaAsP/SiGe tandem solar cells on porous Si substrates

“…The final tail of the EQE (Eg ~1.64 eV) agrees well with the GaAs0.75P0.25 composition determined from the reciprocal space maps, which should correspond to around Eg = 1.66 eV. However, the EQE reaches a maximum of ~50% whereas other works in the literature for similar devices grown by MBE report clearly higher EQEs, as can be observed in the green line corresponding to GaAsP solar cell grown by Grassman and coworkers on Si with GaP nucleation layers and GaAsP graded buffers (Grassman et al 2016). We choose to benchmark our results with (Grassman et al 2016) since the GaAsP top cell has a similar structure -though with a slightly higher bandgap -also grown by MBE and underwent a reactor transfer prior to the growth of the top cell.…”

“…However, the EQE reaches a maximum of ~50% whereas other works in the literature for similar devices grown by MBE report clearly higher EQEs, as can be observed in the green line corresponding to GaAsP solar cell grown by Grassman and coworkers on Si with GaP nucleation layers and GaAsP graded buffers (Grassman et al 2016). We choose to benchmark our results with (Grassman et al 2016) since the GaAsP top cell has a similar structure -though with a slightly higher bandgap -also grown by MBE and underwent a reactor transfer prior to the growth of the top cell. There are better results in the literature (Fan et al 2019, Diaz et al 2015, Grassman et al 2019) that we do not use as a benchmark simply because they were either grown with notably different structures or techniques (MOVPE), or lack sufficient structural information.…”

“…Figure 6 present the results of these simulations for GaAsP subcells grown on: standard Si (Fig. (Grassman et al 2016)). Round symbols correspond to the experimental data.…”

III–V Semiconductor Materials for Solar Hydrogen Production: Status and Prospects

“…Both Si x Ge 1– x , and GaAs y P 1– y , buffers have demonstrated promising results with III–V-on-Si solar cell efficiencies between 15% and 20%. Some groups have also attempted to use the Si substrate as one of the subcells in two- and three-junction configurations. , The record efficiency for III–V-on-Si multijunction cells is currently held by a triple-junction GaInP/GaAs/Si cell fabricated by the Fraunhofer institute that demonstrated a 22.3% photovoltaic efficiency . The epitaxy of GaAs compounds on Si is a dynamic research direction, and ongoing progress will likely encourage cost reductions for III–V-based PEC cells.…”

“…Some groups have also attempted to use the Si substrate as one of the subcells in two-and three-junction configurations. 87,88 The record efficiency for III−V-on-Si multijunction cells is currently held by a triple-junction GaInP/GaAs/Si cell fabricated by the Fraunhofer institute that demonstrated a One of the main arguments against III− V-based water splitting systems is their high cost. The price of the substrate, particularly, accounts for an important part.…”