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In this paper, we report the design and fabrication of fine-pitch and pixelated-addressed micro-light emitting diode (LED) arrays with emission wavelengths of red (R), green (G), blue (B), and infrared (IR). The arrays have a resolution of 8×8 with monochromatic LED chips directly bonded to custom-designed printed circuit boards to form pixelated matrix. R, G, B, and IR micro-LED arrays with a pixel pitch of 1 mm were demonstrated. Sequential row scanning and multiple columns programming is performed by two CMOS-based application specific integrated circuit chips providing constant-sinking current and forward voltage for each pixel of the micro-LED arrays. The uniformity of operating current and forward voltage of the micro-LED pixels was measured with 1.94% coefficient of variation. The micro-LED pixel has much shorter rising time and higher response frequency than those of regular packaged blue and white LEDs. The implemented R-G-B micro-LED arrays are the excellent candidate for high-definition fine-pitch LED displays and demonstrated its versatile functionalities such as visible light communications. The IR micro-LED arrays show great potential in health medical treatment, IR detection imaging and local positioning system.

This paper reported the design and fabrication of a fine pitch, flexible, transparent and pixelated addressable micro‐light‐emitting diode (Micro‐LED) array with a blue emission wavelength. The resolution of the array was 32 × 32. The monochromatic LED chip was directly bonded onto a custom‐designed printed circuit board made of flexible and transparent PET material. A blue flexible transparent Micro‐LED array with a pixel pitch of 0.6 mm was demonstrated. The LED controller was implemented by the custom made FPGA board. The controller controlled the driver board performing sequential row scan and multi‐column scan with constant sink current for each pixel of the Micro‐LED array. Compared with the conventional package of blue and white LED, Micro‐LED pixels have shorter rise time and higher response frequency. In recent years, with the rapid development of medical, micro display and communication network and other fields, integrated Micro‐LED arrays has become the urgent demand of the market. In addition to the characteristics of the planar LED micro arrays, the flexible and transparent Micro‐LED arrays can be applied on the object with curved surface, which has enlarged the application range of the Micro‐LED, and showed great potential for wearable devices, flexible sensors and biomedical applications. [ABSTRACT FROM AUTHOR]