Enabling next-generation
microLED displays

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Mesa sidewall defects are the key factor impacting photodetector performance

Devices such as microLEDs, VCSELs, nanowires, and photodetectors consist of multilayer stacks of different compound semiconductor materials processed to form so-called mesa structures. When the sidewalls and surfaces of mesa structures are exposed to oxygen, the formation of native oxides starts, promoting the formation of defects that act as non-radiative recombination centers.

These defects are the pathway for considerable leakage currents and have a significant impact on photodetector performance (sensitivity, stn ratio, dark-current). As the size of optoelectronic devices decreases, the impact of surface recombination starts to play a very significant role. Kontrox eliminates the majority of surface defects on mesa sidewalls for a significant improvement in device performance and power efficiency.

Application case: microLED

The display industry is coming to a major turning-point due to high demand and unprecedented requirements of power efficiency and brightness driven by next-generation information displays, automotive, VR/AR, and IoT applications. MicroLED technology is currently the only way for that transformation.

There are numerous obstacles in realizing a good quality, high yield, mass-production-ready micro-LED display. Poor efficiency at low current densities and variation of emission level between chips is one of the key issues that is directly related to the quality of the sidewalls of the chips and the high surface recombination effects. These effects become more prominent as the chip size gets smaller.

Kontrox forms a high-quality passivation layer with substantially reduced defect densities improving the microLED's power efficiency & brightness levels significantly