Title :
InGaN/GaN Vertical Light-Emitting Diodes With Diamondlike Carbon/Titanium Heat-Spreading Layers
Author :
Pai Yang Tsai ; Hou Kuei Huang ; Chien-Min Sung ; Ming Chi Kan ; Yeong Her Wang
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng-Kung Univ., Tainan, Taiwan
Abstract :
Vertical light-emitting diodes (VLEDs) with diamondlike carbon/titanium (DLC/Ti) heat-spreading layers on silicon (Si) substrates are investigated. Good thermal conductivity coupled with a thermal expansion coefficient similar to that of gallium nitride enables DLC/Ti to enhance heat dissipation via the Si substrate for Si-bonded VLEDs. The relative light intensity of VLEDs with DLC/Ti operating at 1 A is 10% greater than that of VLEDs without DLC/Ti. The output power droop can be further improved. A slight red shift of 0.5 nm occurs when the injection current is increased from 0.7 to 1 A. VLEDs with DLC/Ti also have lower and more uniform surface temperatures than VLEDs without DLC/Ti. The measured thermal resistance of VLEDs with and without DLC/Ti is 0.63 and 1.51 K/W at an injection current of 350 mA, respectively. This observation shows that the proposed DLC/Ti heat-spreading layer facilitates efficient thermal management in VLEDs.
Keywords :
III-V semiconductors; diamond-like carbon; gallium compounds; indium compounds; light emitting diodes; silicon; thermal conductivity; thermal expansion; thermal management (packaging); titanium; wide band gap semiconductors; C-Ti; DLC-Ti heat-spreading layers; InGaN-GaN; Si; VLED; current 0.7 A to 1 A; current 350 mA; diamondlike carbon-titanium; silicon substrates; thermal resistance; uniform surface temperatures; vertical light-emitting diodes; Diamondlike carbon (DLC); gallium nitride (GaN); light-emitting diode (LED);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2013.2266670
