| 摘要 |
An integrated circuit with an inductor structure includes a semiconductor device substrate. Over the semiconductor device substrate is a dielectric layer, and over the dielectric layer is a metal spiral inductor. The metal spiral is formed by a continuous metal strip. The continuous metal strip has at one end a center and then increases in a radial direction to its other end. The metal spiral carries current between its two ends and generates radial and circumferential parasitic currents in the substrate. In the substrate are a plurality of separated radial doped strips about a central axis. Each of these radial doped strips define a region of relative low resistivity to reduce the resistance to the radial current flow in the device substrate. These strips are separated by regions having relatively high resistivity to substantially maintain the resistance to the circumferential current flow in the substrate. The integrated circuit may also have a metal line extending over the dielectric layer in an incomplete ring around the outer circumference of the metal spiral. This metal line is coupled to at least one site of each of the doped strips and connected either to ground or to the outer end of the metal spiral. Instead of the metal line, the inner end of the metal spiral may be connected to the doped strips. This inductor structure provides a lower resistive or real part of the impedance of the metal spiral, reducing power loss and increasing the Q of the metal spiral.
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