摘要 |
An improved isolation structure for a semiconductor device includes a p-type semiconductor substrate (12) with a p-type well (28) disposed in the substrate (12). A continuous plurality of n-type regions (14, 16, 26) is disposed around the p-type well (28), and the continuous plurality of n-type regions (14, 16, 26) fully isolates the p-type well (28) from the substrate (12) except that the continuous plurality of regions (14, 16, 26) comprises one or more p-type gaps (18) that electrically connect the p-type well (28) to the p-type substrate (12). The use of the gap (18) improves cross-talk suppression in mixed-mode integrated circuits at higher frequencies, for example greater than 50 MHz.
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