Semiconductor substrate and manufacturing method of semiconductor substrate

A semiconductor substrate comprising:

• a substrate body that has a front surface and a rear surface which faces the front surface;
• a front surface electrode formed on the surface;
• and
• a collector electrode formed on the rear surface,
• the substrate body including an element portion and a terminal portion disposed outside the element portion,
• the element portion including an ion implantation layer formed on the rear surface, and
• the ion implantation layer being formed at an angle of 45° or more and 84° or less with respect to the rear surface.

A manufacturing method of a semiconductor substrate, the method comprising:

• a mounting step of mounting a substrate body that has a front surface on which a front surface electrode is formed and a rear surface which faces the front surface on a mounting stage with the rear surface facing upward;
• an ion implantation step of performing ion implantation on the rear surface of the substrate body mounted on the mounting stage to form an ion implantation layer spaced apart from the rear surface;
• a removal step of removing a part of the substrate body from the rear surface to the ion implantation layer by at least one of an etching process and a grinding process;
• and
• an activation step of activating ions implanted into the ion implantation layer by performing a laser annealing treatment on the ion implantation layer after the removal step,
• an implantation energy for performing ion implantation in the ion implantation step being 5 times or more and 10 times or less an implantation energy for performing ion implantation from the rear surface to a depth that is equal to a thickness of the ion implantation layer.

A manufacturing method of a semiconductor substrate, the method comprising:

• a mounting step of mounting a substrate body that has a front surface on which a front surface electrode is formed and a rear surface which faces the front surface on a mounting stage with the rear surface facing upward;
• a treatment step of treating the rear surface of the substrate body mounted on the mounting stage by at least one of an etching process and a grinding process;
• an elimination step of eliminating a foreign substance and a defect on the rear surface of the substrate body by performing a laser annealing treatment on the rear surface after the treatment step;
• an ion implantation step of performing ion implantation on the rear surface of the substrate body to form an ion implantation layer after the removal step;
• and
• an activation step of activating ions implanted into the ion implantation layer by performing a laser annealing treatment on the ion implantation layer.