By Topic

Sapphire-removed induced the deformation of high power InGaN light emitting diodes

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
C. N. Han ; Advanced Microsystem Packaging and Nano-Mechanics Research Lab., Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, 300, Taiwan R.O.C. ; T . L. Chou ; C. F. Huang ; K. N. Chiang

Thick copper films on vertically structures InGaN LEDs play a critical role after sapphire removed. The most commonly used GaN thin film growth technique is metal-organic chemical vapor deposition (MOCVD), which provides a high growth temperature, as a result, high intrinsic stress takes place between sapphire and InGaN surface. If the aforementioned metal supporter experiences a large warpage induced from intrinsic stress after sapphire removed, the subsequent processes would be very difficult to carried out. To solve the above issue, a finite element (FE) numerical simulation was employed for stress-strain behavior analysis of the LED device, the results reveal that, increasing the thickness of metal layer or implementing a pre-metal deposition buffer layer can apparently reduce the device warpage after sapphire removal. Based on the above design concepts, the experimental result depicts that, the warpage of LED wafer can be effectively reduced by 25% when metal layer increased from 62.5 um to 82.5 um, which shows good agreements with FE result, hence validates the established research methodology. And more importantly, based on the process modelling and sapphire-removal simulation-technique developed in this study, an optimal novel LED structure is designed for the reduction of process induced warpage. To conclude, a LED chip structural design-process modeling-fabrication methodology was successfully developed, and can be further contributed to the LED industry.

Published in:

Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Micro-Systems, 2008. EuroSimE 2008. International Conference on

Date of Conference:

20-23 April 2008