Gallium arsenide solar cells grown at rates exceeding 300 µm h−1 by hydride vapor phase epitaxy

Abstract

We report gallium arsenide (GaAs) growth rates exceeding 300 µm h −1 using dynamic hydride vapor phase epitaxy. We achieved these rates by maximizing the gallium to gallium monochloride conversion efficiency, and by utilizing a mass-transport-limited growth regime with fast kinetics. We also demonstrate gallium indium phosphide growth at rates exceeding 200 µm h −1 using similar growth conditions. We grew GaAs solar cell devices by incorporating the high growth rate of GaAs and evaluated its material quality at these high rates. Solar cell growth rates ranged from 35 to 309 µm h −1 with open circuit voltages ranging from 1.04 to 1.07 V. The best devices exceeded 25% efficiency under the AM1.5 G solar spectrum. The high open-circuit voltages indicate that high material quality can be maintained at these extremely high growth rates. These results have strong implications toward lowering the deposition cost of III-V materials potentially enabling the deposition of high efficiency devices in mere seconds.

GaInP/GaAs three-terminal heterojunction bipolar transistor solar cell

“…For example, while traditional 2T devices require highly-doped, transparent tunnel junctions and traditional 3T devices require highly-doped, transparent contact layers in the middle of the structure, the HBTSC requires neither (see Figure 1c). This, combined with the fact that quaternary or metamorphic layers are also not necessary (because of the exibility in E G choice inherent to 3T devices), makes the HBTSC an excellent candidate for the use of emerging materials or for the application of low-cost epitaxial techniques, such as high-throughput epitaxy 26,27 and the sequential growth of many device structures on a single substrate. 28 Different designs of HBTSCs including emerging low-cost materials, such as metal-halide perovskites or nanowires, have already been proposed.…”

Two‐Terminal Direct Wafer‐Bonded GaInP/AlGaAs//Si Triple‐Junction Solar Cell with AM1.5g Efficiency of 34.1%

“…These include efficient use of precursor materials, epitaxial growth rates in metalorganic vapor phase epitaxy (MOVPE) beyond 100 μm h À1 , or hydride vapor phase epitaxy. [6][7][8] There are two approaches to combine III-V and Si solar cells into a triple-junction device: Either by direct growth or layer transfer. Direct growth is attractive from the cost point of view because the cost associated with III-V substrates is avoided but very challenging due to the 4% lattice mismatch and difference in thermal expansion coefficients between Si and GaAs.…”

Stability of Perovskite Light Sources: Status and Challenges

“…Third, the trap densities measured in the perovskites are <10 11 cm −3 , also superior to that of GaAs (>0 14 cm −3 ). [ 57,58 ] A lower trap density is favorable for increasing the radiative recombination. Fourth, MAPbX 3 also shows a large hole mobility of 164 ± 25 cm 2 V −1 s −1 and electron mobility of 24.0 ± 4.1 cm 2 V −1 s −1 , [ 59 ] which are valuable for developing high brightness light‐emitting diodes (LEDs) with lower bias voltages.…”

“…Furthermore, passivation of surface defects was also achieved with submicrometer perovskite structures. Finally, they achieved perovskite LEDs with a maximum EQE of 20.7%, which corresponds to an energy-conversion efficiency of 12%, close to that of the MA based perovskite >2 × 10 4 [53] 375 [55] <10 11 [57] 164 ± 25 [59] 24.0 ± 4.1 [59] GaAs 10 4 [54] <8 [56] >10 14 [58] 491.5 [60] 9400 [60] www.advopticalmat.de state of the art organic LEDs. [61] Recently, high efficiency red and near infrared perovskite LEDs with EQE up to 21.3% and 21.6% have also been reported.…”