Chip and carrier self-contrapositioning soft soldering method under gas protection

Abstract

The invention relates to the self-contraposition soldering of the chip and the carrier under gas protection. It uses the gas protection, the minimum surface energy principle, the precise control of carrier size to realize the self-contraposition. It is characterized in that the method put the carrier, the chip the soldering sheets and the operational tools in the glove-operation box with protective gas, the heating table and the worktable to implement the process. The invention has high soldering efficiency and low damaging rate of the chip.

Description

technical field

[0001] The invention relates to a method for counter-position welding of a chip and a carrier. Background technique

[0002] With the improvement of power density, the increase of the frequency of use of power modules, and the requirements of light, small, vacuum, low temperature, and high reliability of the spaceborne platform, the following principles are proposed for the assembly of power multi-chips: ohmic contact, low thermal resistance Passage, sufficient welding strength and assembly reliability under temperature stress of high and low temperature impact. In addition to the matching of the expansion coefficient of the chip carrier and the chip, and the influence of soldering materials on reliability is very important, the quality of the soldering process between the chip and the carrier is a crucial factor to meet the above three principles

[0003] The soldering effect between the chip and the carrier is not good, resulting in voids, not only the the...

Examples

Embodiment 1

[0033] The concrete operation process of this method is realized through the following steps:

[0034] (1) According to the size of the chip, make the carrier, that is, the substrate or the socket, and the size of the substrate or the welding area of ​​the socket is not greater than 0.05 mm on each side of the chip;

[0035] (2) Gold-plate or silver-plate the carrier, that is, the welding surface of the substrate or the socket so that it can be soldered;

[0036] (3) A flat-plate temperature-controlled heating table with a temperature control accuracy of ±5°C and a flat-plate workbench with an upper limit temperature of up to 450°C are installed in a glove box or airtight operation cabinet filled with protective gas. One of the flat-plate The temperature-controlled heating table can be set to the corresponding temperature as the workbench according to the needs; the carrier, chip, solder piece and operation tools are placed in the glove box or the airtight operation cabinet re...

Embodiment 2

[0040] When the soldering sheet used is a gold-germanium soldering sheet, the thickness of the soldering sheet is about 0.05 mm, the welding temperature is 365-400° C., and the heating time is 3-15 seconds.

[0041]Other technological process is with embodiment 1.

Embodiment 3

[0043] The soldering sheet used is a gold-tin soldering sheet, the thickness of the soldering sheet is about 0.12mm, the soldering temperature is 240-320°C, and the heating time is 3-10 seconds.

[0044] Other technological process is with embodiment 1.

technical field

[0001] The invention relates to a method for counter-position welding of a chip and a carrier. Background technique

[0002] With the improvement of power density, the increase of the frequency of use of power modules, and the requirements of light, small, vacuum, low temperature, and high reliability of the spaceborne platform, the following principles are proposed for the assembly of power multi-chips: ohmic contact, low thermal resistance Passage, sufficient welding strength and assembly reliability under temperature stress of high and low temperature impact. In addition to the matching of the expansion coefficient of the chip carrier and the chip, and the influence of soldering materials on reliability is very important, the quality of the soldering process between the chip and the carrier is a crucial factor to meet the above three principles

[0003] The soldering effect between the chip and the carrier is not good, resulting in voids, not only the the...

Examples

Embodiment 1

[0033] The concrete operation process of this method is realized through the following steps:

[0034] (1) According to the size of the chip, make the carrier, that is, the substrate or the socket, and the size of the substrate or the welding area of ​​the socket is not greater than 0.05 mm on each side of the chip;

[0035] (2) Gold-plate or silver-plate the carrier, that is, the welding surface of the substrate or the socket so that it can be soldered;

[0036] (3) A flat-plate temperature-controlled heating table with a temperature control accuracy of ±5°C and a flat-plate workbench with an upper limit temperature of up to 450°C are installed in a glove box or airtight operation cabinet filled with protective gas. One of the flat-plate The temperature-controlled heating table can be set to the corresponding temperature as the workbench according to the needs; the carrier, chip, solder piece and operation tools are placed in the glove box or the airtight operation cabinet re...

Embodiment 2

[0040] When the soldering sheet used is a gold-germanium soldering sheet, the thickness of the soldering sheet is about 0.05 mm, the welding temperature is 365-400° C., and the heating time is 3-15 seconds.

[0041]Other technological process is with embodiment 1.

Embodiment 3

[0043] The soldering sheet used is a gold-tin soldering sheet, the thickness of the soldering sheet is about 0.12mm, the soldering temperature is 240-320°C, and the heating time is 3-10 seconds.

[0044] Other technological process is with embodiment 1.