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A simplified packaging process was successfully developed for a wafer-level light emitting diode (WL-LED) chip aiming at very-high power solid-state lighting (SSL) applications. Compared with the traditional chip-on-board (COB) technology, WL-LED chip not only greatly simplifies the packaging process but also enables the lighting source more compact. The fabricated blue WL-LED SSL source with a record-high light output power of 305 W exhibits $\sim 30$ % wall plug efficiency at an input electrical power of 1026 W. [ABSTRACT FROM PUBLISHER]

This study designed and tested an innovative light-emitting diode (LED) chip with a built-in sensor. Two electrically isolated units, the LED (for light emission) and the sensor (for monitoring junction temperature and light intensity), were integrated on a single chip. The sensor unit determines the junction temperature by measuring the forward voltage; the light output power of the LED unit can be precisely extrapolated with a polynomial function based on the photocurrent and junction temperature. This novel structure enables the in-situ real-time monitoring of the LED junction temperature and light output power, which allows a highly detailed and/or in-field LED reliability analysis and provides valuable feedback information for smart LED lighting systems. [ABSTRACT FROM PUBLISHER]