Impact of Heat Spreaders on Thermal Performance of III-N-Based Laser Diode

Abstract

This paper explores the effect on optical output power of modifications to the package assembly of a blue-violet III-N-based p-down edge-emitting ridge-waveguide laser diode grown on bulk GaN crystal. The calculations were carried out using a 3-D self-consistent finite-element model. We focus on thermal analyses of the size and thermal conductivity of the heat spreader (mainly made of natural diamond and chemical vapor deposition diamond) and on the thickness of the solder. The results open the possibility for multiple increases in output power, due to a considerable increase in the power conversion efficiency of the laser diode.Index Terms-Computer aided analysis, semiconductor device packaging, semiconductor lasers.

Ultraviolet micro-Raman stress map of polycrystalline diamond grown selectively on silicon substrates using chemical vapor deposition

“…The high thermal conductivity of diamond has motivated efforts for integration with various electronic materials for passive reduction of local heating in devices. 1,2 Polycrystalline diamond, which can be grown on diverse substrates using chemical vapor deposition (CVD), is a prospective heat spreading layer due to improvements reported in thermal performance of power transistors. 3,4 However, the 700-800 C growth temperature used for hotfilament (HF) CVD diamond and the large difference in the coefficient of thermal expansion (CTE) between diamond and the substrate produce thermal stresses in both materials.…”

Thermal Characteristics of a Heat Sink with Bypass Structure for GaN-based Laser Diode

“…레이저 다이오드 패키지 의 열흐름과 방열 특성은 각 구조적 성분들에 의해 결정되 며, 점열원에 의한 열 병목현상이 생기므로 고출력 GaN 기 반의 레이저 다이오드에서 패키지의 방열 최적화 설계가 매 우 중요해졌다 [3,4] . 방열 성능을 개선하기 위해, 다이오드와 히트싱크 사이에 Heat Spreader를 사용하여 열 전달 면적을 넓히는 방법과, [5] 다이오드와 히트싱크 접합부의 Solder의 방 열 성능을 개선시키는 방법 등이 사용되고 있으나, [6] 수직 구 조로 설계된 레이저 다이오드 좁은 발열부에서는 구조 전체 를 효율적으로 이용하지 못하고, 다이오드와 히트싱크 등 접 합부의 물리적 크기 차이에 의한 병목현상으로 방열특성 개 선에 한계가 있다. 접합부의 병목현상을 개선하기 위해 수평 방향의 우수한 열전도도를 갖는 그래핀층을 접합부에 추가 하는 방법 [7] 이 있지만 상용제품의 반도체 패키지 과정에서 Table 1.…”

Interface Contact Thermal Resistance of Die Attach in High-Power Laser Diode Packages

“…Kuc and Otiaba. KC et al focused on thermal analysis of the size of the diamond heat sink and on the thickness of the solder [8,9]. Ma.…”

“…Although the aforementioned studies provide vital information on the package thermal resistance of laser diodes, they were more concentrated on the impact of chip size, solder void, heat sink, and submount materials on thermal resistance [6][7][8][9][10][11]. There are few papers researching the influence of interface between the chip and solder or solder and heat sink on package thermal resistance in high-power laser diodes.…”