Packaging structure and packaging method of silicon photonic optical module

Abstract

The invention discloses the packaging structure and its packaging method of a silicon optical module.The encapsulation structure of a silicon optical module of the present invention, including: PCBA circuit board, CUW base, CUW lid, silicon optical chip launch unit, silicon optical chip receiving unit, driving chip, cross -resistant large chip and semiconductor cold device (TEC TEC); The open window area is provided on the PCBA circuit board; the surface edges of the under -opening area are the fourth coordination surface;; The upper edge of the CUW base is the first coordination surface; the CUW base also has a second cooperation surface and the third coordination surface;fit.The beneficial effect of the present invention: The height difference between the CUW structure and the suction mouth with a high control function to eliminate the height difference between the silicon optical chip and the IC chip, thereby reducing the length of the golden key between the pads between different chips.

Description

technical field [0001] The invention relates to the field of semiconductor packaging, in particular to a packaging structure of a silicon photonic optical module and a packaging method thereof. Background technique [0002] Silicon photonics technology has been generally recognized by the optical communication industry as the core technology of next-generation optical communication devices and module systems, and it is one of the most promising solutions to solve the problems of data center interconnection rate limitation, cost, and power consumption. Silicon photonics technology is compatible with CMOS technology, and integrates a series of optical components such as light source, modulator, detector, multiplexer / demultiplexer, and waveguide on a single silicon substrate, which greatly reduces the raw material production cost of photonic chips and optical modules. packaging and testing costs. Silicon photonics technology can greatly improve the integration of devices and r...

AI Technical Summary

Problems solved by technology

[0006] The first is to use COB packaging, and its technical defects mainly have two points

The first point: the high-speed signal line connects the silicon photonics chip transmitting unit and receiving unit to the Driver chip and the TIA chip respectively through gold wire bonding, and connects the Driver chip and the TIA chip to the PCBA circuit board in the same way; in the high-speed optical module In the circuit, especially at a rate above 25Gbps, the shorter the gold wire bonding length, the better the integrity of high-frequency signal transmission; however, the length of the gold wire bonding depends on the silicon photonic chip, IC chip, and PCBA pad. The distance between them includes the horizontal and vertical directions; the COB package cannot control the height difference of different chip pads in the vertical direction, which is unfavorable for the length control of gold wire bonding, which in turn causes the bonding length to be too large and affects high-frequency signals integrity

The second point: directly attaching the silicon photonic chip emission unit to the PCBA circuit board does not control the heat dissipation of the laser well, which leads to the temperature characteristic drift of the laser and modulator, and affects the quality of the optical signal generation of the silicon photonic module.

[0007] The second is to adopt the TROSA package form, and its technical defects mainly have two points

The first point: the same as the COB package, that is, the height difference of different chip pads in the vertical direction cannot be controlled, which is unfavorable for the control of the gold wire bonding length and affects signal integrity.

The second point: this type of packaging needs to connect the FPC pads to the PCBA pads by thermocompression welding, the process reliability is not good, resulting in low production yield; on the other hand, this type of packaging process is complex, increasing production and Package cost

Images