| 摘要 |
<p>A semiconductor device is provided to lower the resistance of a semiconductor device by having a drain layer made of a through electrode structure instead of an impurity layer. A through hole(10) is formed in a semiconductor substrate(1) of first conductivity type, extending from the front surface of the semiconductor substrate to the back surface of the substrate. The through hole is coated with a first metal layer(18) formed on the back surface of the semiconductor substrate. A drain layer(11) is formed in the through hole, electrically connected to the first metal layer. The drain layer further includes a second metal layer(13) in contact with the surface of the semiconductor substrate such that the second metal layer is formed on the surface of the semiconductor substrate. A first insulation layer can be formed on the sidewall part of the through hole. The drain layer can includes a third metal layer(14) covering the first insulation layer and the second metal layer.</p> |
