Semiconductor device
AssigneeRenesas Electronics Corporation
InventorsYasuhiro Okamoto, Nobuo Machida, Kenichi Hisada
Life of this patent
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Abstract
In a Schottky barrier diode region, a Schottky barrier diode is formed between an n-type drift layer and a metal layer, and in a body diode region, a p-type semiconductor region, a p-type semiconductor region, and a p-type semiconductor region are formed in order from a main surface side in the drift layer, and a body diode is formed between the p-type semiconductor region and the drift layer. An impurity concentration of the p-type semiconductor region is decreased lower than the impurity concentration of the p-type semiconductor regions, thereby increasing the reflux current flowing through the Schottky barrier diode and preventing the reflux current from flowing through the body diode.
Claims15
A semiconductor device, comprising:
- a first main surface having a first region as a formation region of a body diode and a second region as a formation region of a Schottky barrier diode,
- a second main surface as an opposite side to the first main surface,
- a first semiconductor layer having a first conductivity type,
- a second semiconductor layer arranged on the second main surface, having the first conductivity type and having an impurity concentration higher than that of the first semiconductor layer,
- a first semiconductor region having a second conductivity type opposite to the first conductivity type and formed in the first semiconductor layer so as to expose to the first main surface side in the first region,
- a second semiconductor region having the second conductivity type and formed on the second main surface side with respect to the first semiconductor region in the first semiconductor region,
- a third semiconductor region having the second conductivity type and formed between the first semiconductor region and the second semiconductor region, and
- a metal layer formed on the first main surface in the first and the second regions, wherein
- an impurity concentration of the third semiconductor region is lower than that of the first and the second semiconductor regions,
- a body diode is configured between the second semiconductor region and the first semiconductor layer in the first region, and
- a Schottky barrier diode is configured between the metal layer and the first semiconductor layer in the second region.
A semiconductor device, comprising:
- a first main surface having a first region as a formation region of a body diode and a second region as a formation region of a Schottky barrier diode,
- a second main surface as an opposite side to the first main surface,
- a first semiconductor layer having a first conductivity type,
- a second semiconductor layer arranged on the second main surface, having the first conductivity type and having a high impurity concentration than the first semiconductor layer,
- a first semiconductor region having a second conductivity type opposite to the first conductivity type and formed in the first semiconductor layer so as to expose to the first main surface side in the first region,
- a second semiconductor region having the second conductivity type and formed on the second main surface side with respect to the first semiconductor region in the first region,
- a metal layer formed on the first main surface in the first and the second regions, wherein
- the second semiconductor region is arranged separately from the first semiconductor region,
- a portion of the first semiconductor layer is interposed between the second semiconductor region and the first semiconductor region,
- an impurity concentration of the second semiconductor region is lower than that of the first semiconductor region,
- a body diode is configured between the second semiconductor region and the first semiconductor layer in the first region, and
- a Schottky barrier diode is configured between the metal layer and the first semiconductor layer in the second region.
Dependencies are inferred from the claim text.