| Summary: | 碩士 === 國立中興大學 === 精密工程學系所 === 97 === This thesis discussed the effects of laser lift-off (LLO) and surface roughness applicated on flip-chip (FC) and fabricated a device with photonic crystal structure on n-GaN surface combined with high reflectivity mirror. The samples of thin film flip-chip (TFFC) were fabricated on unpatterned (Flat) and patterned substrate (PSS). Fabrication of photonic crystal (PC) structures, with period of 450nm, 600nm, and 900nm, on n-GaN surface were bonded to silicon substrate with aluminum mirror by transparent adhesive layer. Finally, the measurement of each layer thermal resistance was tested with thermal resistance method.
On the leakage current, drove on -5 V, all samples presented less than 1uA performance. On the optical characteristic, a 350 mA current injection to encapsulated TFFC-double rough(DR)-Flat-LED enhanced 36.2% output power as compared with FC-single rough(SR)-Flat-LED, whereas TFFC-DR-PSS-LED increased 7.4% as compared with FC-SR-PSS-LED. Si-450nm-PC-LED, Si-600nm-PC-LED, and Si-900nm-PC-LED increased 28.2%, 32.7%, and 20.2%, as compared with Sapphire-SR-LED.
The power efficiency of FC-SR-Flat-LED, TFFC-DR-Flat-LED, FC-SR-PSS-LED, TFFC-DR-PSS-LED, Sapphire-SR-LED, Si-450 nm-PC-LED, Si-600 nm-PC-LED, and Si-900 nm-PC-LED are 14.33%, 20.96%, 10.83%, 14.54%, 16.18%, 16.38%, 20.05%, and 15.59%, respectively, whereas light extraction efficiency are 30.69%, 41.82%, 49.81%, 53.51%, 51.08%, 65.47%, 67.79% and 61.39%, repectively.
|
|---|
