Semiconductor device having diode devices with different barrier heights and manufacturing method thereof
A Schottky diode device includes a substrate having a first conductivity type, a first well region having a second conductivity type disposed in the substrate, and a first doped region having the second conductivity type in the first well region, wherein the first doped region includes a first portion and a second portion, and the first portion and the second portion have different doping concentrations. The first portion includes a region having at least four sides, from a top-view perspective, abutting the second portion.
1. A Schottky diode device, comprising:
a substrate having a first conductivity type;
a first well region having a second conductivity type disposed in the substrate; and
a first doped region having the second conductivity type in the first well region, the first doped region comprising a first portion and a second portion, and the first portion and the second portion having different doping concentrations,
wherein the first portion comprises a region having at least four sides, from a top-view perspective, abutting the second portion.
2. The Schottky diode device according to claim 1 , further comprising a metal containing layer on the first doped region.
3. The Schottky diode device according to claim 1 , further comprising an isolation structure disposed in the substrate and at least surrounding the first well region from a top view perspective.
4. The Schottky diode device according to claim 1 , wherein the first conductive type is different from the second conductive type.
5. The Schottky diode device according to claim 1 , wherein the first well region defines an anode zone and a cathode zone, and each of the anode zone and the cathode zone overlaps the first doped region.
6. The Schottky diode device according to claim 5 , further comprising a second doped region disposed in the cathode zone and exposed from an upper surface of the substrate.
7. The Schottky diode device according to claim 5 , further comprising a third doped region on an upper surface of the substrate at a periphery of the anode zone and having the first conductive type.
8. The Schottky diode device according to claim 5 , wherein the first portion and the second portion extends through the anode zone and the cathode zone.
9. The Schottky diode device according to claim 1 , further comprising:
a gate layer on the substrate;
source/drain regions in the substrate on two sides of the gate layer; and
a lightly doped region (LDD) in the substrate between the gate layer and the respective source/drain regions.
10. The Schottky diode device according to claim 1 , wherein the first portion comprises concentric rings alternatingly arranged with concentric rings of the second portion.
11. A semiconductor device, comprising:
a substrate;
a first well region in the substrate; and
a first doped region in the first well region, wherein the first doped region comprises a first portion and a second portion alternating with each other, and the first portion and the second portion have different doping concentrations,
wherein the first portion comprises a plurality of first concentric rings and the second portion comprises a plurality of second concentric rings.
12. The semiconductor device according to claim 11 , wherein the first concentric rings are alternatively arranged with the second concentric rings.
13. The semiconductor device according to claim 11 , wherein each of the first concentric rings has a first width, and each of the second concentric rings has a second width different from the first width.
14. The semiconductor device according to claim 11 , wherein the first doped region is doped with an N-type dopant.
15. The semiconductor device according to claim 11 , further comprising:
a second well region in the substrate; and
a second doped region within the second well region, wherein the second doped region comprises a third portion and a fourth portion alternating with the third portion, wherein a first area ratio between the first portion and the second portion is different from a second area ratio between the third portion and the fourth portion.
16. The semiconductor device according to claim 11 , further comprising an isolation structure extending in the substrate and defining the first well region, wherein the first doped region has a depth less than the isolation structure.
17. The semiconductor device according to claim 16 , wherein the first well region extends below the isolation structure.
18. The semiconductor device according to claim 11 , further comprising a metal-containing layer on the first doped region.
19. A Schottky diode device, comprising:
a substrate having a first conductivity type;
a first well region having a second conductivity type disposed in the substrate;
a first doped region having the second conductivity type in the first well region, the first doped region comprising a first portion and a second portion, and the first portion and the second portion having different doping concentrations; and
a second doped region having the second conductivity type over the first doped region in the first well region,
wherein the first doped region defines a first zone and a second zone separated from the first zone, and the second doped region is disposed in the second zone.
20. The Schottky diode device according to claim 19 , wherein both of the first portion and the second portion extends across the first zone and the second zone.