State Key Lab for Mesoscopic Physics and School of Physics, Peking University, Beijing, 100871, China.
Department of Mechanical Engineering, University of California, Berkeley, CA, 94720, USA.
Adv Mater. 2018 Feb;30(8). doi: 10.1002/adma.201704333. Epub 2018 Jan 8.
The best performing modern optoelectronic devices rely on single-crystalline thin-film (SC-TF) semiconductors grown epitaxially. The emerging halide perovskites, which can be synthesized via low-cost solution-based methods, have achieved substantial success in various optoelectronic devices including solar cells, lasers, light-emitting diodes, and photodetectors. However, to date, the performance of these perovskite devices based on polycrystalline thin-film active layers lags behind the epitaxially grown semiconductor devices. Here, a photodetector based on SC-TF perovskite active layer is reported with a record performance of a 50 million gain, 70 GHz gain-bandwidth product, and a 100-photon level detection limit at 180 Hz modulation bandwidth, which as far as we know are the highest values among all the reported perovskite photodetectors. The superior performance of the device originates from replacing polycrystalline thin film by a thickness-optimized SC-TF with much higher mobility and longer recombination time. The results indicate that high-performance perovskite devices based on SC-TF may become competitive in modern optoelectronics.
表现最佳的现代光电设备依赖于外延生长的单晶薄膜（SC-TF）半导体。通过低成本的溶液法合成的新兴卤化物钙钛矿在各种光电设备中取得了巨大的成功，包括太阳能电池、激光、发光二极管和光电探测器。然而，迄今为止，基于多晶薄膜有源层的这些钙钛矿设备的性能落后于外延生长的半导体设备。在此，报道了一种基于 SC-TF 钙钛矿活性层的光电探测器，其具有创纪录的 5000 万增益、70 GHz 增益带宽产品和 100 光子级检测极限，在 180 Hz 调制带宽下，据我们所知，这是所有报道的钙钛矿光电探测器中的最高值。该器件的优越性能源于用厚度优化的 SC-TF 替代多晶薄膜，从而获得更高的迁移率和更长的复合时间。结果表明，基于 SC-TF 的高性能钙钛矿器件可能在现代光电领域具有竞争力。
