High-power MOS tube and making method

Abstract

The disclosed MOS tube in large power includes electrodes, and contact hole. The contact hole includes through hole, which passes through different layers in semiconductor device, and conducting material in the through hole. Being connected to electrode at bottom of the contact hole, the conducting material is cobalt-silicon alloy. The invention also discloses method for manufacturing the MOS tube in large power. After contact hole is formed by current technique, the invention adds three procedures in sequence: cobalt sputtering, rapid thermal anneal, and removing non-reactive cobalt. The MOS tube in large power prepared by using the disclosed method possesses features: contact hole of MOS tube provides smaller resistance under condition of small size, and raises reliability of MOS tube in large power.

Description

technical field [0001] The invention relates to a structure of a MOS tube, in particular to a high-power MOS tube. The invention also relates to a manufacturing method of a high-power MOS tube. Background technique [0002] Due to its wider application range than previous bipolar devices, power MOS devices have become the mainstream of today's power device development. Due to the high current and low switching loss requirements for power devices, deep trench high-power MOS transistors have become the mainstream of power MOS transistors. [0003] As power MOS devices are more applied to communication equipment and personal portable electronic devices, the requirements for the reliability of power MOS devices are gradually increasing. In terms of process technology, it is necessary to continuously reduce the size of the original cell and increase the integration of the original cell. Today's high-power MOS transistors with deep trench structures usually use TiSi (titanium-s...

AI Technical Summary

Problems solved by technology

[0015] Devices using Ti / TiN as a contact barrier are prone to reliability problems when they are packaged later

Usually this is because when Ti and highly doped silicon form an alloy, it will penetrate into a very deep place in the silicon, so that the current can easily penetrate into a very deep place during the post-packaging work, which will cause the device to fail.

[0016] In addition, with the further shrinkage of the lateral and vertical dimensions of the device, the contact hole area gradually becomes smaller, the resistivity formed by TiSi is large and unstable, and the large resistivity of the contact area also leads to the UIS (unclamped induction spike effect) of the device. ) characteristics of the reduction

Images