Alleviating the crosstalk effect via a fine-moulded light-blocking matrix for colour-converted micro-LED display with a 122% NTSC gamut

One of the major challenges when fabricating high gamut colour-converted micro-light-emitting diodes (LEDs) displays is severe crosstalk effect among adjacent pixels because of the wide view-angle feature of micro-LED chips. In this study, potential factors that contribute to the crosstalk effect were systematically simulated. We observed that precisely filling the space between each micro-LED chip with a light blocking matrix (LBM) can be a promising solution to alleviate this risk. After careful investigations, a press-assisted moulding technique was demonstrated to be an effective approach of fabricating the LBM. Nevertheless, experimental observations further revealed that residual black LBM on the surface of micro-LEDs severely reduces the brightness, thereby compromising the display performance. This problem was successfully addressed by employing a plasma etching technique to efficiently extract the trapped light. Eventually, a top-emitting blue micro-LED-based backlight fine-moulded with a black LBM was developed and combined with red and green quantum dot colour-conversion layers for full-colour display. The colour gamut of our manufactured display prototype can cover as high as 122% that of the National Television Standards Committee.