Periodic Organic–Inorganic Halide Perovskite Microplatelet Arrays on Silicon Substrates for Room‐Temperature Lasing

Abstract

Organic–inorganic metal halide perovskites have recently demonstrated outstanding efficiencies in photovoltaics as well as highly promising performances for a wide range of optoelectronic applications such as lasing, light emission, optical detectors, and even for radiation detection. Key to the realization of functional perovskite micro/nanosystems on the ubiquitous silicon optoelectronics platform is through sophisticated lithography. Despite the rapid progress made in halide perovskite lasing, direct lithographic patterning of perovskite films to form optical cavities on conventional substrates remains extremely challenging. This study realizes room‐temperature high‐quality factor whispering‐gallery‐mode lasing (Q ≈ 1210) from patterned lead halide perovskite microplatelets fabricated in periodic arrays on silicon substrate with micropatterned BN film as the buffer layer. By varying the size of the platelets, modal selectivity for single mode lasing can be achieved with different cavity sizes or by simply breaking the structural symmetry of the cavity through designing the pattern. Importantly, this work demonstrates a straightforward, versatile bottom‐up scalable strategy to realize high‐quality periodic perovskite arrays with variable cavity sizes for large‐area light‐emitting and optical gain applications.

Two‐Dimensional Metal Halide Perovskites: Theory, Synthesis, and Optoelectronics

“…They also used the two‐step method: lead iodide microplatelets were deposited on a patterned substrate, and then methylammonium lead iodide perovskites were prepared under CH 3 NH 3 I vapor. Liu et al did similar work; the different point is that they used single‐layer hexagonal boron nitride (h‐BN) as a buffer layer between the Si substrate and the perovskite arrays: the h‐BN can provide growth nuclei, which makes it easy to obtain nanoplatelets. Meanwhile, the single layer can also be a superior insulating dielectric layer and cladding layer for better optical confinement.…”

“…Copyright 2014, Wiley‐VCH. c,d) Output (c) and transfer (d) characteristics of an FET based on a perovskite microplate crystal at 77 K. Reproduced with permission . Copyright 2015, AAAS.…”

“…Wang and co‐workers prepared a field‐effect transistor (FET) to measure the electrical properties of 2D organic–inorganic perovskite crystals . As Figure c,d show, the conductance increased with an increase in the positive gate voltage, which indicates that the perovskite crystal shows an n‐type behavior.…”

“…2D perovskites are used as a whispering‐gallery‐mode cavity while 1D perovskite nanowires can also be used for Fabry–Pérot mode cavities. Liu et al used 400 nm femtosecond pulses to pump the 2D perovskite CH 3 NH 3 PbI 3 . As the pulse fluence increased from 8.4 µJ cm −2 to 11 µJ cm −2 , a series of sharp peaks appeared and the intensity increased in the emission spectrum because optical feedback in the whispering‐gallery‐mode cavity amplified the excitation light.…”

Chip‐Scale Fabrication of Uniform Lead Halide Perovskites Microlaser Array and Photodetector Array

“…[33] Soon after, perovskite microplate-based photodetector arrays and field-effect transistor arrays were experimentally realized. [34] Meanwhile, Feng et al have synthesized single crystal perovskite microplate laser arrays by splitting the solutions into periodic arrays with a silicon micropillar structure. [35] In 2017, by using more generic polydimethylsiloxane (PDMS) microstructures, all-inorganic lead halide perovskite microlasers were also synthesized.…”