Silicon carbide power semiconductor device having uniform channel length and manufacturing method thereof

A method of manufacturing a power semiconductor device, comprising:

• (a) forming a plurality of body regions of a second conductivity type to be spaced apart from each other with a preset separation width WS in a horizontal direction in an upper region of a drift region epitaxially grown on a silicon carbide substrate of a first conductivity type;
• (b) forming, by an ion implant of the first conductivity type with a first mask, a low-resistance region of the first conductivity type in an upper region of a separation space between adjacent body regions of the plurality of body regions to contact side surfaces of the adjacent body regions, and forming a source region of the first conductivity type in a surface region in a body region of the plurality of body regions in contact with the low-resistance region to be spaced apart from the low-resistance region by a preset channel length;
• and
• (c) forming, by an ion implant of the first conductivity type with the first mask, a JFET region of the first conductivity type with a width equal to the separation width WS in a lower region of the separation space,
• wherein in (b), the low-resistance region forms an overlap region in a lateral direction by an overlap length OL1 with a first adjacent body region of the plurality of body regions in a first direction, and forms an overlap region in the lateral direction by an overlap length OL2 with a second adjacent body region of the plurality of body regions in a second direction opposite to the first direction so as to be formed with a width of WS+OL1+OL2,
• wherein an ion implant concentration in (c) is set relatively lower than an ion implant concentration of the plurality of body regions so that the each body region of the plurality of body regions is maintained at a lower region of the source region and a lower portion of the low-resistance region that does not overlap with the plurality of body regions,
• wherein the source region and the low-resistance region are formed using the first mask, such that when the overlap length OL1 and the overlap length OL2 do not match each other due to misalignment between the source region and the plurality of body regions, the preset channel length between the low-resistance region and the source regions on both sides remains constant.