CMOS image sensor

Patent metadata

Field	Value
Publication number	US-10340304-B2
Application number	US-201816019281-A
Country	US
Kind code	B2
Filing date	Jun 26, 2018
Priority date	Jan 7, 2016
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

The present disclosure provides CMOS image sensors. A CMOS image sensor includes a substrate having a first region and a second region connecting with the first region at a first end of the first region; a transfer transistor formed on the surface of the substrate in the second region; a floating diffusion (FD) region formed in the surface of the substrate at one side of the transfer transistor in the second region; a third implanting region formed in the surface of the substrate 200 in the first region, being formed from a first implanting region; a second implanting region and an adjacent fifth implanting region formed under the third implanting region; and a fourth implanting region formed under the second implanting region and the fifth implanting region, being electrically connected with the third implanting region by the fifth implanting region.

First claim

What is claimed is:

1. A CMOS image sensor, comprising:
a substrate having a first region and a second region connecting with the first region at a first end of the first region;
a transfer transistor formed on the surface of the substrate in the second region;
a floating diffusion (FD) region formed in the surface of the substrate at one side of the transfer transistor in the second region;
a third implanting region formed in the surface of the substrate in the first region, being formed from a first implanting region;
a second implanting region and an adjacent fifth implanting region formed under the third implanting region; and
a fourth implanting region formed under the second implanting region and the fifth implanting region, being electrically connected with the third implanting region by the fifth implanting region, wherein the third implanting region and the fourth implanting region have side surfaces coinciding with an edge of the transfer transistor.

2. The CMOS image sensor according to the claim 1 , further comprising:
a sixth implanting region formed in the surface of the substrate in a second region overlapping a portion of a first region and a portion of the surface of the substrate adjacent to first region.

3. The CMOS image sensor according to claim 1 , further comprising:
a pinning layer covering the third implanting region, the floating diffusion layer and the surface of the substrate.

4. The CMOS image sensor according to claim 1 , wherein:
the substrate has a first conductive type;
the first implanting region has a second conductive type opposite to the first conductive type;
the second implanting region has the first conductive type;
the third implanting region and the fourth implanting region have the second conductive type; and
the fifth implanting region has the second conductive type.

5. The CMOS imaging sensor according to claim 4 , wherein:
the first implanting region is formed by a first ion implantation process, a second ion implantation process and a third ion implantation process.

6. The CMOS imaging sensor according to claim 4 , wherein:
a conductive type of ions of the first ion implantation process, the second ion implantation process and the third ion implantation process is the second conductive type.

7. The CMOS imaging sensor according to claim 5 , wherein:
energies of the first ion implantation process, the second ion implantation process and the third ion implantation process are gradually increased.

8. The CMOS imaging sensor according to claim 1 , wherein:
ions implanted in the second implanting region are boron ions;
an energy of the ion plantation process for forming the second implanting region is approximately 160 KeV; and
a dosage of boron ions is approximately 3.5E12 atom/cm 2 .

9. The CMOS imaging sensor according to claim 1 , wherein:
ions implanted in the fifth implanting region are phosphor ions;
an energy of the ion implantation process for forming the fifth implanting region is approximately 250 KeV; and
a dosage of phosphor ions is approximately 3E12 atom/cm 2 .

10. The CMOS imaging sensor according to claim 1 , further including:
a pinning layer formed in the surface of the substrate by an ion implantation process.

11. The CMOS imaging sensor according to claim 10 , wherein:
ions of the ion implantation process are BF 2 ions;
an energy of the ion implantation process is approximately 30 KeV; and
a dosage of the BF 2 ions is approximately 5E12 atom/cm 2 .

12. The CMOS imaging sensor according to claim 1 , further including:
a sixth implanting region formed in the surface of the substrate by an ion implantation process using the second mask.

13. The CMOS imaging sensor according to claim 12 , wherein:
ions of the ion implantation process are BF 2 ions;
an energy of the ion implantation process is approximately 30 KeV; and
a dosage of BF 2 ions is approximately 5E12 atom/cm 2 .

14. The CMOS image sensor according to the claim 2 , wherein:
the third implanting region, the fourth implanting region, and the fifth implanting region form a U-shaped implanting region.

15. The CMOS image sensor according to the claim 14 , wherein:
the sixth implanting region covers the U-shaped implanting region and isolates the U-shaped implanting region from a channel region under the transfer transistor.

16. The CMOS image sensor according to the claim 2 , wherein:
the sixth implanting region has a side surface coinciding with the side surfaces of the third implanting region and the fourth implanting region.

17. The CMOS image sensor according to the claim 1 , wherein:
the fifth implanting region protrudes from the side surfaces of the third implanting region and the fourth implanting region.

Assignees

• Semiconductor Mfg Int Shanghai Corp
• Semiconductor Mfg Int Beijing Corp

Inventors

• Jung Dae-Sub
• Chen Deyan
• Shi Xuejie

Classifications

• H10P30/22

  using masks · CPC title

• H01L27/1461

  Electricity · mapped topic

• H01L27/14612

  Electricity · mapped topic

• H01L27/14689

  Electricity · mapped topic

• H01L27/14643 Primary

  Electricity · mapped topic