| 摘要 |
A Schottky recitfier includes a semiconductor body and a rectifying interface between the semiconductor body and a metal layer. A plurality of trenches are formed in the surface of the semiconductor body, the trenches being separated by mesas, and regions of a conductivity type opposite to the conductivity type of the body is formed along the sidewalls and bottoms of the trenches, the regions forming PN junctions with the rest of the mesas. When the rectifier is reverse-biased, the depletion regions along the PN junctions merge to occupy the entire width of the mesas, thereby protecting the rectifying interface from barrier lowering and resulting current leakage. The use of trenches allows a high aspect ratio, i.e., the ratio of the length to the width of the current "channels" in the mesas (the length being equal to the depth of the trenches), thereby maximizing the area available for current flow and reducing the resistance of the rectifying device in the forward direction. In many embodiments the aspect ratio is greater than one. The device is fabricated by implanting dopant directly through the sidewalls and bottoms of the trenches, by filling the trenches with a material containing dopant and causing the dopant to diffuse through the sidewalls and bottoms of the trenches, or by implanting and diffusing the dopant into a gate filling material wherein the diffusivity of the dopant in the gate filler is greater than the diffusivity of the dopant in the semiconductor material.
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