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We report the demonstration of monolithically integrated light-emitting diodes (LEDs) and power metal-oxide-semiconductor channel high-electron-mobility transistors (HEMTs) in GaN. The structure comprised a direct epitaxial integration of layers typical for a GaN-based LED grown directly on top of the layers of a GaN-based HEMT. The layers were then fabricated into a serially connected pair of GaN LED and metal-oxide-semiconductor-gated 0.3 lm-channel HEMT by exposing the LED/HEMT epitaxial layers in selective area etching. The resulting monolithically integrated circuit shows a full gate voltage modulation of the light output power. This demonstrates compatibility of group-III nitride LED and HEMT processes. V C 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4807125]GaN-based high-power light-emitting diodes (LEDs) used in lighting applications typically require dedicated electronic driver circuits for AC-DC power conversion, current sourcing, and dimming using pulse-width modulation (PWM) or analog current control methods. 1 GaN power switching field-effect transistors (FETs), such as metaloxide-semiconductor (MOS) FETs, high-electron-mobility transistors (HEMTs), and MOS-Channel HEMTs (MOSCHEMTs) have shown outstanding performance in terms of high breakdown voltage (BV), low specific on-resistance, and high operating frequency, 2-4 and can be very useful as output devices for emerging applications of high power-high voltage LED systems. Ultimately, monolithic integration of GaN-based LEDs and GaN power HEMTs can reduce the cost and the size of solid state lighting systems, improve system reliability, and serve as a technology platform for the development of light-emitting power integrated circuits (LEPICs). LEPICs can also play an important role in adding functionalities required for emerging solid state lighting applications such as visible light communication (VLC) and other LED control technologies required for future smart lighting applications. 5

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To elucidate the fundamentals of chemical mechanical polishing (CMP) of silicon nitride, low pressure chemical vapor deposited silicon nitride is analyzed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy both before and after CMP, demonstrating the salient increase of oxygen content, amine species, and silanol groups forming on the nitride surface. In addition, chemical testing of the collected slurry identifies ammonia as one of the nitride reaction products during CMP. Nitride hydrolysis is proposed as the dominant chemical reaction, through which the nitride surface is chemically modified and softened, enabling continuous material removal with a process that achieves atomic-scale surface smoothness. Moreover, the nitride polish rate can be promoted or suppressed through the modulation of the nitride hydrolysis.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.6.218.72 Downloaded on 2015-04-05 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.6.218.72 Downloaded on 2015-04-05 to IP