COB packaging method for expanding working temperature window of optical module

Abstract

The invention discloses a COB packaging method for expanding a working temperature window of an optical module, which comprises the following steps of: S1, determining the required thickness of a substrate by calculating the power consumption of a chip and the area of the substrate according to the requirement of the calculated temperature difference between the upper part and the lower part of the substrate, and sticking the substrate on a metal layer, coating the surface of a substrate with the metal layer, pasting a laser and a detector chip in the optical module on the substrate, and laying a circle of copper sheet on the peripheral frame of a PCB so that a gap of 1-2mm can be reserved between the PCB and the copper sheet below the chip; and S2, then placing aTEC in two modes, whereinone mode is horizontal placement, and the other mode is vertical placement. When the TEC is placed horizontally, one side of the cold surface of the TEC is connected with the metal layer on the uppersurface of the substrate, one side of the hot surface of the TEC is connected with the grounding copper sheet layer laid on the outer ring of the PCB and a module upper shell, and when the TEC is placed vertically, one side of the TEC hot surface is connected with the metal layer on the upper surface of the substrate and one side of the TEC cold surface is connected with the module upper shell.

Description

technical field [0001] The invention relates to the technical field of 4G LTE and 5G fronthaul system application and industrial automation control, and specifically relates to a COB packaging method for expanding the working temperature window of an optical module. Background technique [0002] The optical transceiver module (CXP, QSFP, CFP, etc.) is an important component of the optical fiber access network. Chip on Board (COB) technology, that is, the chip is mounted on the surface of the printed board, and the electrical connection between the chip and the substrate is realized by wire bonding. The traditional COB package optical module, the chip is mounted on the copper surface of the PCB board , The module and the shell are in direct contact with the heat-conducting glue and the heat-dissipating boss, and the heat accumulated when the chip is working is dissipated through the shell. The high and low temperature test of optical modules can effectively screen unqualifie...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a COB packaging method that expands the working temperature window of the optical module to solve the problem that the traditional COB packaged optical module has a narrow chip working temperature window and the heat generated by the optical chip during high temperature testing. The temperature of the PCB body increases rapidly, which seriously reduces the working life of the chip. At the same time, the excessive heat will also have a great impact on the performance of the module itself. Low temperature will also cause poor performance of the product itself

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