High-thermal-conductivity metal bonding structure and manufacturing method

Abstract

The invention relates to a high-thermal-conductivity metal bonding structure and a manufacturing method. The high-thermal-conductivity metal bonding structure is characterized in that a reflective metal layer and a molybdenum metal layer which are used for heat conduction or / and light reflection are arranged below a VCSEL (surface emitting laser) element, the number of epitaxial layer pairs of a non-main light-emitting surface DBR (distributed Bragg reflector layer) is reduced by utilizing the high reflectivity of the reflective metal layer, and the heat generated by the VCSEL element during light emitting is easily conducted to the external environment through the high heat conduction coefficient value between the molybdenum metal layer and a substrate connected with the molybdenum metallayer so as to dissipate the heat of the whole VCSEL element; and the numerical value of the coefficient of thermal expansion between the molybdenum metal layer and the substrate is quite close, and the amount of linear thermal expansion generated by the molybdenum metal layer and the substrate is quite close, so that the VCSEL element has small residual stress so as to prolong the service life ofthe VCSEL element.

Description

Technical field[0001]The present invention relates to a metal bonding structure with high thermal conductivity and a manufacturing method, in particular to a structure that is easy to dissipate heat, components can have a small residual stress, maintain the original structure without macroscopic warping and peeling, and avoid The generation and propagation of microscopic lattice defects, as well as the high thermal conductivity metal bonding structure that can enhance light reflection and the manufacturing method of the structure.Background technique[0002]Press, as the name implies, the Vertical Cavity Surface-Emitting Laser (VCSEL) is emitted vertically from the surface of the crystal grain, mainly using the upper and lower two DBR mirror layers (distributed Braggreflector, DBR for short, also known as distributed The Bragg reflector layer) forms a laser resonant cavity.[0003]Such asfigure 1 As shown, first, on a laser wafer substrate composed of gallium arsenide (GaAs) as the subs...

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Problems solved by technology

However, the above-mentioned conventional VCSEL element has the following defects: 1. The substrate 91 is made of GaAs, and the thermal conductivity of GaAs is 46W / m·K, and the printed film directly in contact with the substrate 91 The circuit board P is made of epoxy resin, the thermal conductivity of the printed circuit board P is 0.2W / m·K, and the thermal conductivity of the printed circuit board P is 1 / 230 of the thermal conductivity of the substrate 91, so the VCSEL element The generated high heat will accumulate on the base 91 and cannot be smoothly guided to the printed circuit board P. The high heat accumulated on the base 91 will not only reduce the operating efficiency of the entire VCSEL element, but may also cause the VCSEL element to burn out; 2. The thermal expansion coefficient (Coefficient of Thermal Expansion, CTE) of this substrate 91 (gallium arsenide substrate) is 6.8x10 -6 / K, the thermal expansion coefficient of the printed circuit board P is 67.1x10 -6 / K, the thermal expansion coefficient of the printed circuit board P is 9.9 times that of gallium arsenide. In other words, the printed circuit board P is more prone to thermal expansion and deformation than the substrate 91. It will warp from the printed circuit board P to the substrate 91, and even cause the printed circuit board P to peel off from the substrate 91, resulting in failure and damage to the VCSEL element

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