Micropore Filling Provided A New Idea For The Patterning Of Perovskite Quantum Dots

Micro-LED display technology is considered to be the next generation display technology. However, its large-scale commercialization still faces the challenge of immature technology and high cost. One of the challenges is how to realize the full color of Micro-LED.

The technical route of using blue Micro-LED combined with quantum dot color converter (QDCC) is a feasible full-color solution. The quantum dot color conversion technology only need to manufacture a blue Micro-LED display with high pixel density as a whole, and convert some of its blue pixels into red and green through a QDCC to achieve full-color display. In addition, QDCC can also be used as color conversion layers for OLED and color filters for LCD to improve efficiency and color gamut.

Perovskite quantum dots (PQDs) are suitable for the fabrication of QDCC due to their excellent optical properties. At present, researchers have developed several QDCC fabrication techniques, including inkjet printing, lithography, and microcontact printing. The competitive fabrication method for QDCC is photolithography, as it provides good pattern quality with high resolutions, great reproducibility, and wafer-scale manufacturing. However, due to the lack of suitable photoresists for PQDs, only a few works can realize the dual-color QDCC with a pixel size less than 10 μm.

In order to solve the preparation problem of high resolution QDCC, the team of LIANG Jingqiu from Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) and the team of ZHONG Haizheng from Beijing Institute of Technology (BIT) developed a micropore filling technology to fabricate high resolution QDCC.

This technology mainly includes two key steps of perovskite quantum dot filling and surface polishing. The researchers successfully fabricated a QDCC with a minimum pixel size of 2 μm, and realized the preparation of the dual-color QDCC through the overlay technology. The QDCC with a pixel size of 60 μm exhibits high fluorescence uniformity of 3.22% ± 0.61%.

The micropore filling fabrication provides a flexible and versatile method to fabricate QDCC with potential advantages of low production cost, and fast processing speed which provides a new idea for the patterning of perovskite quantum dots, and provides a feasible method for realizing full-color Micro-LED display.

The related research was published in Nanoscale and was included in the 2022 Nanoscale HOT Article Collection.