Patent ID: 8659152
Filing Date: 2014-02-25
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a semiconductor substrate including a first main surface and a second main surface opposing the first main surface; and a hole penetrating in the semiconductor substrate between the first and second main surfaces, and including a tapered portion contacting with the first main surface and a vertical portion contacting with the tapered portion and the second main surface, the tapered portion comprising at least first and second scallop openings in that order from the first main surface toward the vertical portion, each of the first and second scallop openings including a first end close to the first main surface and a second end close to the second main surface, the first and second scallop openings respectively including first and second convex side surface, the convex side surface being defined such that a diameter of the hole at the second end of each of the first and second scallop openings is smaller than a diameter of the hole at an intermediate point between the first and second ends of the respective first and second scallop openings, the second end of the first scallop opening contacting with the first end of the second scallop opening, a first diameter of the hole at the second end of the first scallop opening being larger than a second diameter of the hole at the second end of the second scallop opening, the vertical portion comprising a plurality of scallop openings arranged in series, the plurality of scallop openings each including a convex side surface, and a plurality of third diameters of the hole at respective connecting points of two scallop openings adjacently arranged among the plurality of scallop openings being substantially the same as one another and smaller than the second diameter.