Vertical power devices having retrograded-doped transition regions therein
AssigneeSilicon Semiconductor Corporation
InventorBantval Jayant Baliga
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Abstract
Power MOSFET devices provide highly linear transfer characteristics (e.g., Id v. Vg) and can be used effectively in linear power amplifiers. These linear transfer characteristics are provided by a device having a channel that operates in a linear mode and a drift region that simultaneously supports large voltages and operates in a current saturation mode. A relatively highly doped transition region is provided between the channel region and the drift region. Upon depletion, this transition region provides a potential barrier that supports simultaneous linear and current saturation modes of operation. Highly doped shielding regions may also be provided that contribute to depletion of the transition region.
Claims11
A vertical power device, comprising:
- a semiconductor substrate;
- a drift region of first conductivity type in said semiconductor substrate;
- first and second spaced-apart base regions of second conductivity type in said semiconductor substrate;
- first and second source regions of first conductivity type in said first and second base regions, respectively;
- a transition region of first conductivity type that extends between said first and second base regions, forms a non-rectifying junction with the drift region and has a vertically retrograded first conductivity type doping profile relative to a surface of said semiconductor substrate;
- and
- an insulated gate electrode that extends on the surface and opposite said first base region and said transition region.
Dependencies are inferred from the claim text.