Thermal and Optical Properties of InGaN/GaN Green Vertical Light-Emitting Diodes on Molybdenum Substrate for Different Submounts

摘要

We reported the thermal and optical properties of InGaN/GaN multiple quantum wells green (λ ～ 525 nm) vertical light-emitting diodes (VLEDs) with a large chip size of 1 × 1 mm~2 on molybdenum substrate. In the temperature range of 298-358 K, the temperature-dependent measurement of the packaged VLEDs on metal printed circuit board (MPCB) submount was performed, indicating a characteristic temperature of ～456K at 350 mA. At 298 K and 350 mA, the optical output power, operating voltage, and peak emission wavelength were measured to be 110.7mW, 3.52 V, and 524.1 nm, respectively, and the view angle of Lambertian radiation pattern was about 120° at full width at half maximum. The forward voltage method was used to measure the junction temperature (T_j) of VLED devices. From the measured T_j values, the thermal resistance (R_(th)) value was experimentally obtained to be ～14.62 K/W for VLEDs on the MPCB. In comparison, the R_(th) value of the devices on copper submount was decreased to ～9.16K/W.