Single-photon avalanche diodes

1 . A structure comprising:

a first deep trench structure in a semiconductor substrate comprising a conductive material and a material of a first polarity which is provided on a sidewall of the conductive material of the first deep trench structure;

a second deep trench structure in the semiconductor substrate surrounding the first deep trench structure, the second deep trench structure comprising a conductive material and a material of a second polarity which is provided on sidewalls of the conductive material of the second deep trench structure; and

contacts to both the first deep trench structure and the second deep trench structure.

2 . The structure of claim 1 , wherein the first deep trench structure comprises an anode and the second deep trench structure comprises a cathode, the material of the first polarity surrounds the conductive material of the first deep trench structure and the material of the second polarity surrounds the conductive material of the second deep trench structure.

3 . The structure of claim 1 , wherein electric field lines are provided radially in a horizontal plane in an active area along a depth and between the first deep trench structure and the second deep trench structure.

4 . The structure of claim 1 , wherein the second deep trench structure completely surrounds the first deep trench structure, the first deep trench structure and the second deep trench structure are separated by the semiconductor substrate with the material of the first polarity facing the material of the second polarity.

5 . The structure of claim 1 , wherein the first deep trench structure and the second deep trench structure form a circular structure.

6 . The structure of claim 1 , wherein the first deep trench structure and the second deep trench structure form a polygonal shaped structure.

7 . The structure of claim 1 , wherein the first deep trench structure and the second deep trench structure extend to a backside of the semiconductor substrate.

8 . The structure of claim 1 , wherein the second deep trench structure extends to a backside of the semiconductor substrate and the first deep trench structure extends completely through the semiconductor substrate.

9 . The structure of claim 2 , wherein the material of the first polarity comprises N+ semiconductor material on sidewalls of the first deep trench structure and the material of the second polarity comprises P+ semiconductor material on the sidewalls of the second deep trench structure.

10 . The structure of claim 2 , wherein the material of the first polarity comprises P+ semiconductor material on sidewalls of the first deep trench structure and the material of the second polarity comprises N+ semiconductor material on the sidewalls of the second deep trench structure.

11 . The structure of claim 10 , wherein the conductive material comprises a non-transparent material.

12 . The structure of claim 10 , wherein the conductive material of the anode comprises polysilicon with the first polarity and the conductive material of the cathode comprises polysilicon with the second polarity.

13 . A structure comprising:

a deep trench anode extending into a semiconductor substrate, the deep trench anode comprising a P+ doped sidewall on a sidewall of a conductive material;

a deep trench cathode surrounding the deep trench anode and extending into the semiconductor substrate, the deep trench cathode comprising an N+ doped sidewall on a sidewall of the conductive material, the P+ doped sidewall being a different polarity than the N+ doped sidewall; and

a contact provided to both the deep trench anode and the deep trench cathode.

14 . The structure of claim 13 , wherein the deep trench cathode completely surrounds the deep trench anode, the P+ doped sidewall surrounds the conductive material of the deep trench anode and the N+ doped sidewall surrounds the conductive material of the deep trench cathode.

15 . The structure of claim 13 , wherein the deep trench cathode and the deep trench anode extend to a backside of the semiconductor substrate and the deep trench anode and the deep trench structure cathode are separated by the semiconductor substrate with the P+ doped sidewall facing the N+ doped sidewall.

16 . The structure of claim 13 , wherein the deep trench cathode extends to backside of the semiconductor substrate and the deep trench anode extends completely through the semiconductor substrate, and the contact to the deep trench cathode comprises the conductive material of the deep trench cathode.

17 . The structure of claim 13 , wherein the conductive material comprises non-transparent material.

18 . The structure of claim 13 , wherein the deep trench cathode, the deep trench anode and the semiconductor substrate comprise a P-i-N single-photon avalanche diode.

19 . A method comprising:

forming a first deep trench structure in a semiconductor substrate comprising a conductive material and a material of a first polarity which is provided on a sidewall of the conductive material of the first deep trench structure;

forming a second deep trench structure in the semiconductor substrate surrounding the first deep trench structure, the second deep trench structure comprising a conductive material and a material of a second polarity, different than the first polarity, the material of the second polarity being on sidewalls of the conductive material of the second deep trench structure; and

forming contacts to both the first deep trench structure and the second deep trench structure.

20 . The method of claim 19 , wherein the first deep trench and the second deep trench cause horizontal movement of charge with an electric field in a horizontal direction throughout a depth of the first deep trench and the second deep trench.