Ice-assisted electron-beam lithography for halide perovskite optoelectronic nanodevices

Abstract

Metal halide perovskites (MHPs) have received substantial attention due to their impressive optoelectronic properties. In particular, nanoscale perovskite structures, such as nanowires (NWs) and nanoplates (NPs) are ideal building blocks for optoelectronic devices. However, metal electrodes can be hardly patterned on these materials with conventional lithographic methods due to the solvent sensitivity of perovskite crystals and alignment issues. Here, we report a solvent-free method to fabricate metal electrodes on perovskite NPs, which starts with the vapor deposition of water ice as an electron resist and ends in the sublimation of the ice followed by a “blow-off” process. The good compatibility between MHPs and ice as well as the in-situ imaging and patterning process guarantees the fabrication with high precision and resolution. Using this technique, we create metal electrodes on single-crystal MAPbBr3 NPs featuring a nanoscale gap of 296 nm and superior photodetection ability with responsivity of 653 A/W and detectivity of 3.08 × 1013 Jones. Our study helps the widely-used electron-beam lithography break down barriers in processing perovskite materials, and provides an excellent platform to fully exploit their potentials in optoelectronic devices.