Semiconductor device and manufacturing method thereof

Abstract

A semiconductor device has an n--semiconductor layer and p+-diffusion regions each having a depth of 14 to 20 mum (design value) selectively formed in the n- semiconductor layer. With the entire surface of the chip irradiated with light ions, such as He ions, a lifetime killer is introduced from a position d 2 shallower than a position d 1 of a p-n junction surface, formed from the n--semiconductor layer and the p+-diffusion regions, to a position d 3 deeper than the position d 1 to form a short-lifetime region over the entire chip. The irradiation is carried out so that the light ion irradiation half width is not more than the depth of the p+-diffusion regions and a position of a peak of the light ions becomes deeper than the light ion irradiation half width and within the range between 80% and 120% of the depth of the p+-diffusion regions. Thus, in a semiconductor device such as a converter diode, a capability for a high decay rate of a reverse recovery current di / dt can be brought sufficiently high to such an extent that the device can withstand a lightening surge with a low forward voltage VF being kept low.

Description

technical field [0001] The present invention relates to a semiconductor device mounted on a module such as a power supply module and a manufacturing method thereof, and more particularly to a semiconductor device and a manufacturing method thereof which are highly resistant to lightning strikes applied to the semiconductor module. Background technique [0002] Image 6 is a circuit diagram showing an example of an automotive power supply module. like Image 6 As shown in , the power module is configured with a converter section 1 , an interrupt section 2 , an inverter section 3 and a thermistor 4 . The converter part 1 has converter diodes 5, which generally each consist of a PIN diode. For example, for a module with a rated voltage of 1200V or 600V, a PIN diode with a breakdown voltage of 1600V or higher or 800V or higher, respectively, would be used as a converter diode 5 . [0003] The reason why a breakdown voltage greater than the rated voltage is required is that som...

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Problems solved by technology

This complicates the production process and leads to an increase in chip cost

[0018] Furthermore, although a region with short-lived carriers is formed locally in the depth direction of the chip surface or near the surface by using helium ions or protons, sufficient di / dt capability cannot be obtained

Further, in the case of heavy metals being diffused as lifetime inhibitors, it is difficult to control the depth of diffusion of the heavy metals

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