Monolithic multi-I region diode limiters
A number of monolithic diode limiter semiconductor structures are described. The diode limiters can include a hybrid arrangement of diodes with different intrinsic regions, all formed over the same semiconductor substrate. In one example, two PIN diodes in a diode limiter semiconductor structure have different intrinsic region thicknesses. The first PIN diode has a thinner intrinsic region, and the second PIN diode has a thicker intrinsic region. This configuration allows for both the thin intrinsic region PIN diode and the thick intrinsic region PIN diode to be individually optimized. The thin intrinsic region PIN diode can be optimized for low level turn on and flat leakage, and the thick intrinsic region PIN diode can be optimized for low capacitance, good isolation, and high incident power levels. This configuration is not limited to two stage solutions, as additional stages can be used for higher incident power handling.
1. A monolithic diode limiter semiconductor structure, comprising:
a first PIN diode comprising a first P-type region formed to a first depth into an intrinsic layer such the first PIN diode comprises a first effective intrinsic region of a first thickness;
a second PIN diode comprising a second P-type region formed to a second depth into the intrinsic layer such the second PIN diode comprises a second effective intrinsic region of a second thickness; and
at least one blocking capacitor and at least one inductor.
2. The monolithic diode limiter semiconductor structure of claim 1 , wherein the first thickness is greater than the second thickness.
3. The monolithic diode limiter semiconductor structure of claim 1 , wherein the at least one blocking capacitor and the at least one inductor are formed over the intrinsic layer as part of the monolithic diode limiter semiconductor structure.
4. The monolithic diode limiter semiconductor structure of claim 1 , wherein:
a cathode of the first PIN diode is electrically coupled to ground in the monolithic diode limiter semiconductor structure; and
a cathode of the second PIN diode is electrically coupled to the ground in the monolithic diode limiter semiconductor structure.
5. The monolithic diode limiter semiconductor structure of claim 1 , further comprising:
a dielectric layer over the intrinsic layer, the dielectric layer comprising a plurality of openings, wherein:
the first P-type region is formed through a first opening among the plurality of openings; and
the second P-type region is formed through a second opening among the plurality of openings.
6. The monolithic diode limiter semiconductor structure of claim 5 , wherein a first width of the first opening is different than a second width of the second opening.
7. The monolithic diode limiter semiconductor structure of claim 1 , further comprising:
at least one transmission line, wherein the at least one blocking capacitor, the at least one inductor, and the at least one transmission line are formed over the intrinsic layer as part of the monolithic diode limiter semiconductor structure.
8. The monolithic diode limiter semiconductor structure of claim 1 , wherein the first PIN diode and the second PIN diode are heterolithic microwave integrated circuit (HMIC) PIN diodes.
9. The monolithic diode limiter semiconductor structure of claim 1 , further comprising a third PIN diode comprising a third P-type region formed to a third depth into the intrinsic layer such the third PIN diode comprises a third effective intrinsic region of a third thickness.
10. The monolithic diode limiter semiconductor structure of claim 9 , wherein:
the first thickness is greater than the second thickness; and
the second thickness is greater than the third thickness.
11. The monolithic diode limiter semiconductor structure of claim 1 , further comprising an N-type silicon substrate, wherein the intrinsic layer is formed on the N-type silicon substrate.
12. The monolithic diode limiter semiconductor structure of claim 1 , further comprising an N-type silicon substrate, wherein the first PIN diode and the second PIN diode are both formed on the N-type silicon substrate.
13. The monolithic diode limiter semiconductor structure of claim 1 , wherein the diode limiter comprises a multistage hybrid diode limiter of at least two stages.
14. A monolithic semiconductor structure, comprising:
a first diode comprising a first intrinsic region of a first thickness;
a second diode comprising a second intrinsic region of a second thickness, the first thickness being greater than the second thickness; and
at least one blocking capacitor.
15. The monolithic semiconductor structure of claim 14 , wherein:
the first diode comprises a first P-type region formed to a first depth into an intrinsic layer of the monolithic semiconductor structure; and
the second diode comprising a second P-type region formed to a second depth into the intrinsic layer of the monolithic semiconductor structure.
16. The monolithic semiconductor structure of claim 15 , wherein the at least one blocking capacitor is formed over the intrinsic layer as part of the monolithic semiconductor structure.
17. The monolithic semiconductor structure of claim 14 , wherein:
a cathode of the first diode is electrically coupled to ground in the monolithic semiconductor structure; and
a cathode of the second diode is electrically coupled to the ground in the monolithic semiconductor structure.
18. The monolithic semiconductor structure of claim 14 , further comprising:
a dielectric layer over an intrinsic layer of the monolithic semiconductor structure, the dielectric layer comprising a plurality of openings, wherein:
a first P-type region is formed through a first opening among the plurality of openings; and
a second P-type region is formed through a second opening among the plurality of openings.
19. The monolithic semiconductor structure of claim 18 , wherein a first width of the first opening is different than a second width of the second opening.
20. The monolithic semiconductor structure of claim 14 , wherein the first diode and the second diode are heterolithic microwave integrated circuit (HMIC) PIN diodes.