The miniaturization of light-emitting diodes (LEDs) is pivotal in ultrahigh-resolution displays. Metal-halide perovskites promise efficient light emission, long-range carrier transport and scalable manufacturing for bright microscale LED (micro-LED) displays. However, thin-film perovskites with inhomogeneous spatial distribution of light emission and unstable surface under lithography are incompatible with the micro-LED devices. Continuous single-crystalline perovskite films with eliminated grain boundaries, stable surfaces and optical homogeneity are highly demanded for micro-LEDs, but their growth and device integration remain challenging. Here we realize the remote-epitaxy growth of crystalline perovskite films, enabling their seamless integration into micro-LEDs with a pixel size down to 4 μm. By incorporating a subnanometre graphene interlayer, we enable remote epitaxy and transfer of perovskites with relaxed strain. These micro-LEDs exhibit a high electroluminescence efficiency of 16.7% and a high brightness of 4.0 × 10⁵ cd m⁻². Such high performance stems from suppressed defects and efficient carrier transport in epitaxial perovskites with high crystallinity, relaxed strain and hundreds-of-nanometres thickness. The free-standing perovskites can be integrated with commercial electronic planes for independent and dynamic control of each pixel, thus facilitating both static image and video display. With these findings, we envision on-chip perovskite photonic sources such as ultracompact lasers and ultrafast LEDs.

发光二极管 （LED） 的小型化在超高分辨率显示器中至关重要。金属卤化物钙钛矿有望为明亮的微型 LED （micro-LED） 显示器提供高效的光发射、长距离载流子传输和可扩展的制造。然而，光刻下发光空间分布不均匀且表面不稳定的薄膜钙钛矿与 micro-LED 器件不兼容。micro-LED 对消除晶界、稳定表面和光学均匀性的连续单晶钙钛矿薄膜提出了很高的要求，但它们的生长和器件集成仍然具有挑战性。在这里，我们实现了晶体钙钛矿薄膜的远程外延生长，使其能够无缝集成到像素尺寸低至 4 μm 的 micro-LED 中。通过结合亚纳米石墨烯夹层，我们实现了具有松弛应变的钙钛矿的远程外延和转移。这些 micro-LED 具有 16.7% 的高电致发光效率和 4.0 × 10⁵ cd m⁻² 的高亮度。如此高性能源于外延钙钛矿中抑制的缺陷和高效的载流子传输，具有高结晶度、松弛应变和数百纳米厚度。独立式钙钛矿可与商用电子平面集成，对每个像素进行独立和动态控制，从而促进静态图像和视频显示。凭借这些发现，我们设想了片上钙钛矿光子源，例如超紧凑型激光器和超快 LED。