摘要
Single-junction,lattice-mismatched In0.69Ga0.31As thermophotovoltaic（TPV） devices each with a bandgap of 0.6 eV are grown on InP substrate by metal-organic chemical vapour deposition（MOCVD）.Compositionally undulating stepgraded InAsyP1-y buffer layers with a lattice mismatch of ～1.2% are used to mitigate the effect of lattice mismatch between the device layers and the InP substrate.With an optimized buffer thickness,the In0.69Ga0.31As active layers grown on the buffer display a high crystal quality with no measurable tetragonal distortion.High-performance single-junction devices are demonstrated,with an open-circuit voltage of 0.215 V and a photovoltaic conversion efficiency of 6.9% at a short-circuit current density of 47.6 mA/cm2,which are measured under the standard solar simulator of air mass 1.5-global（AM 1.5 G）.
Single-junction,lattice-mismatched In0.69Ga0.31As thermophotovoltaic（TPV） devices each with a bandgap of 0.6 eV are grown on InP substrate by metal-organic chemical vapour deposition（MOCVD）.Compositionally undulating stepgraded InAsyP1-y buffer layers with a lattice mismatch of ～1.2% are used to mitigate the effect of lattice mismatch between the device layers and the InP substrate.With an optimized buffer thickness,the In0.69Ga0.31As active layers grown on the buffer display a high crystal quality with no measurable tetragonal distortion.High-performance single-junction devices are demonstrated,with an open-circuit voltage of 0.215 V and a photovoltaic conversion efficiency of 6.9% at a short-circuit current density of 47.6 mA/cm2,which are measured under the standard solar simulator of air mass 1.5-global（AM 1.5 G）.
基金
Project supported by the National Basic Research Program of China (Grant No. 61176128)
the Knowledge Innovation Project of the Chinese Academy of Sciences
Suzhou Municipal Solar Cell Research Project,China (Grant No. SYG201145)
