Manufacture method of VDMOS device with irradiation resistance

Abstract

The invention discloses a manufacture method of a VDMOS device with irradiation resistance. The manufacture method of the VDMOS device is characterized by forming a gate oxide layer, evaporating aluminum on the gate oxide layer, and then diffusing aluminum at high temperature to form a gate medium of an Si-O-Al structure. Positive charges accumulated in the gate medium can be reduced when the VDMOS device is irradiated; the resistance to total dose irradiation of the device is improved; meanwhile, compared with the conventional silicon dioxide gate medium, the gate medium of the Si-O-Al structure is higher in dielectric constant; the resistance to single event gate rupture of the device can be improved. The manufacture method can be used for effectively overcoming the contradiction of requirements on the thickness of the resistance to total dose irradiation and the single event gate rupture and optimizing the resistance to total dose irradiation and the single event gate rupture at the same time; the process is simple; the resistance to the irradiation of the VDMOS device is improved.

Description

technical field [0001] The invention relates to a method for manufacturing a VDMOS device with anti-radiation performance, belonging to the field of semiconductor device manufacturing. Background technique [0002] VDMOS is widely used in power circuits of space systems due to its advantages of fast switching speed, high input resistance, good frequency characteristics, high driving capability, and high transconductance linearity. There are a large number of charged particles and cosmic rays in the space, which will cause the parameters and performance of the device to degrade, and may fail in severe cases. In order to ensure the normal operation of the spacecraft, the anti-radiation reinforcement of VDMOS is of great significance. [0003] The total annual radiation dose received by earth satellites in near-earth orbit is 10Krad, and the total annual radiation dose received by earth satellites in far-earth orbit is 1000Krad. The performance degradation of VDMOS devices af...

AI Technical Summary

Problems solved by technology

However, reducing the thickness of the gate oxide layer will increase the electric field generated by the same amount of holes in the gate dielectric when the device is incident by heavy particles, which is not conducive to the resistance to single event gate breakdown.

The improvement of the quality of the oxide layer is also subject to the limitations of the raw materials themselves, and there are inevitably defects.

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