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Information × Registration Number 0214U008165, 0109U004885 , R & D reports Title Experimental technique design for measuring micro-pattern of light and temperature in high-power light emitting structures operated in extreme conditions popup.stage_title Head Malyutenko Volodimir, Registration Date 26-09-2014 Organization Institute of Semiconductor Physics of NAS of Ukraine popup.description2 New approach to estimate the quality and key figures of merit of light emitting diodes (LEDs) and emitting structure has been developed. We experimentally have shown that classic one-dimensional integral approach cannot be used in еру extreme power mode as it is unable to supply with the details of spatial distribution of current and temperature in the active device region. Experimental test system able to visualize two-dimensional light and heat patterns (spatial and temporal resolution of <20 ?m and <20 ?s, correspondingly, spectral range-visible, near- and middle infrared bands) was developed and tested. By examining LEDs from brand companies (Cree, Osram, Seoul semiconductor, Lumiled) and UA suppliers we have mentioned some negative aspects of technology, which are responsible for low efficiency of the devices. We have shown experimentally that non-uniform current distribution (current crowding) followed light crowding and large temperature gradients inside a structure, is responsible for low LED performance and their dynamic and static degradation. It was proved that performance and stability of LEDs could be remarkably improved provided more attention is paid to electrical efficiency of devices. The details and recommendations on how to improve LED technology was proposed. Product Description popup.authors Болгов С. С. Кірюша О. І. Лисенко С.О. Малютенко О. Ю. Тихонов А. М. popup.nrat_date 2020-04-02 Close