Method for manufacturing array substrate, array substrate and fingerprint recognition device

1. A method for manufacturing an array substrate comprising a plurality of target region groups, each target region groups comprising a PIN-type diode and a transistor, and the method for manufacturing the array substrate comprising steps of:

forming a plurality of polysilicon patterns on a substrate, the plurality of polysilicon patterns comprising a first polysilicon pattern for forming the PIN-type diode and a second polysilicon pattern for forming the transistor, each polysilicon pattern comprising a first sub-region, a second sub-region, and a third sub-region between the first sub-region and the second sub-region;

using a first doping process to dope the first sub-region of the first polysilicon pattern, and the first sub-region and the second sub-region of the second polysilicon pattern with one of P-type ions and N-type ions, respectively; and

using a second doping process to dope the second sub-region of the first polysilicon pattern with the other of the P-type ions and the N-type ions;

wherein the transistor comprises a P-type transistor and an N-type transistor and the second polysilicon pattern comprises a third polysilicon pattern for forming the P-type transistor and a fourth polysilicon pattern for forming the N-type transistor, the fourth polysilicon pattern further comprises two fourth sub-regions located between the first sub-region and the third sub-region and between the second sub-region and the third sub-region, respectively; and

wherein the step of using the first doping process to dope the first sub-region of the first pattern with the one of P-type ions and N-type ions, respectively comprises steps of:

forming a metal layer on the plurality of polysilicon patterns, and performing a first patterning to the metal layer so that the metal layer covers the fourth polysilicon pattern, the third sub-region of the third polysilicon pattern, and the second sub-region and the third sub-region of the first polysilicon pattern: and

doping the first sub-region of the first polysilicon pattern, and the first sub-region and the second sub-region of the third polysilicon pattern with the P-type ions. to form a P-doped. region of the PIN-type diode and a P-doped region of the P-type transistor.

2. The method according to claim 1 ,

wherein the step of using the second doping process to dope the second sub-region of the first polysilicon pattern with the other of the P-type ions and the N-type ions comprises steps of:

performing a second patterning to the metal layer so that the metal layer covers the third sub-region of the fourth polysilicon pattern, the third sub-region of the third polysilicon pattern, and the second sub-region and the third sub-region of the first polysilicon pattern;

forming a first photoresist layer, and performing a first patterning to the first photoresist layer so that the first photoresist layer covers the third sub-region and the fourth sub-region of the fourth polysilicon pattern, the third polysilicon pattern, and the first polysilicon pattern; and

doping the first sub-region and the second sub-region of the fourth polysilicon pattern with the N-type ions, to form an N-doped region of the N-type transistor.

3. The method according to claim 2 , wherein the step of using the second doping process to dope the second sub-region of the first polysilicon pattern with the other of the P-type ions and the N-type ions further comprises steps of:

performing a second patterning to the first photoresist layer so that the first photoresist layer covers the third sub-region of the fourth polysilicon pattern, the third polysilicon pattern, and the first polysilicon pattern; and

doping the fourth sub-region of the fourth polysilicon pattern, to form a lightly-doped drain region of the N-type transistor.

4. The method according to claim 3 , wherein the first polysilicon pattern further comprises a fourth sub-region located between the second sub-region and the third sub-region, and

wherein the step of using the second doping process to dope the second sub-region of the first polysilicon pattern with the other of the P-type ions and the N-type ions further comprises steps of:

performing a third patterning to the metal layer so that the metal layer covers the third sub-region of the fourth polysilicon pattern, the third sub-region of the third polysilicon pattern, and the third sub-region of the first polysilicon pattern;

forming a second photoresist layer, and performing a first patterning to the second photoresist layer so that the second photoresist layer covers the fourth polysilicon pattern, the third polysilicon pattern, and the first sub-region, the third sub-region and the fourth sub-region of the first polysilicon pattern; and

doping the second sub-region of the first polysilicon pattern with the N-type ions, to form an N-doped region of the PIN-type diode.

5. The method according to claim 4 , wherein, after the step of doping the second sub-region of the first polysilicon pattern with the N-type ions, the method further comprises steps of:

performing a second patterning to the second photoresist layer so that the second photoresist layer covers the fourth polysilicon pattern, the third polysilicon pattern, and the first sub-region and the third sub-region of the first polysilicon pattern; and

doping the fourth sub-region of the first polysilicon pattern, to form a lightly-doped drain region of the PIN-type diode.

6. The method according to claim 1 , wherein the first polysilicon pattern further comprises a fourth sub-region located between the second sub-region and the third sub-region, and

wherein the step of using the second doping process to dope the second sub-region of the first polysilicon pattern with the other of the P-type ions and the N-type ions comprises:

performing a second patterning to the metal layer so that the metal layer covers the third sub-region of the fourth polysilicon pattern, the third sub-region of the third polysilicon pattern, and the third sub-region of the first polysilicon pattern;

forming a fifth photoresist layer, and performing a first patterning to the fifth photoresist layer so that the fifth photoresist layer covers the third sub-region and the fourth sub-region of the fourth polysilicon pattern, the third polysilicon pattern, and the first sub-region, the third sub-region and the fourth sub-region of the first polysilicon pattern; and

doping the first sub-region and the second sub-region of the fourth polysilicon pattern and the second sub-region of the first polysilicon pattern with the N-type ions, to form an N-doped region of the N-type transistor and an N-doped region of the PIN-type diode.

7. The method according to claim 6 , wherein, after the step of doping the first sub-region and the second sub-region of the fourth polysilicon pattern and the second sub-region of the first polysilicon pattern with the N-type ions, to form the N-doped region of the N-type transistor and the N-doped region of the PIN-type diode, the method further comprises steps of:

performing a second patterning to the fifth photoresist layer so that the fifth photoresist layer covers the third sub-region of the fourth polysilicon pattern, the third polysilicon pattern, and the first sub-region and the third sub-region of the first polysilicon pattern; and

doping the fourth sub-region of the fourth polysilicon pattern and the fourth sub-region of the first polysilicon pattern, to form a lightly-doped drain region of the N-type transistor and a lightly-doped drain region of the PIN-type diode.

8. The method according to claim 1 , wherein the first polysilicon pattern further comprises a fourth sub-region located between the second sub-region and the third sub-region, and

wherein the step of using the first doping process to dope the first sub-region of the first polysilicon pattern, and the first sub-region and the second sub-region of the second polysilicon pattern with one of the P-type ions and the N-type ions respectively comprises steps of:

forming a metal layer on the plurality of polysilicon patterns, and performing a first patterning to the metal layer so that the metal layer covers the third sub-region of the fourth polysilicon pattern, the third sub-region of the third polysilicon pattern, and the third sub-region of the first polysilicon pattern;

forming a sixth photoresist layer, and performing a first patterning to the sixth photoresist layer so that the sixth photoresist layer covers the third sub-region and the fourth sub-region of the fourth polysilicon pattern, the third polysilicon pattern, and the first sub-region, the third sub-region, and the fourth sub-region of the first polysilicon; and

doping the first sub-region and the second sub-region of the fourth polysilicon pattern and the second sub-region of the first polysilicon pattern with the N-type ions, to form an N-doped region of the N-type transistor and an N-doped region of the PIN-type diode.

9. The method according to claim 8 , wherein, after the step of doping the first sub-region and the second sub-region of the fourth polysilicon pattern and the second sub-region of the first polysilicon pattern with the N-type ions, to form the N-doped region of the N-type transistor and the N-doped region of the PIN-type diode, the method further comprises steps of:

performing a second patterning to the sixth photoresist layer so that the sixth photoresist layer covers the third sub-region of the fourth polysilicon pattern, the third polysilicon pattern, and the first sub-region and the third sub-region of the first polysilicon pattern; and

doping the fourth sub-region of the fourth polysilicon pattern and the fourth sub-region of the first polysilicon pattern, to form a lightly-doped drain region of the N-type transistor and a lightly-doped drain region of the PIN-type diode.

10. The method according to claim 9 , wherein the step of using the second doping process to dope the second sub-region of the first polysilicon pattern with the other of the P-type ions and the N-type ions further comprises steps of:

forming a seventh photoresist layer, and patterning the seventh photoresist layer so that the seventh photoresist layer covers the fourth polysilicon pattern, the third sub-region of the third polysilicon pattern, and the second sub-region, the third sub-region and the fourth sub-region of the first polysilicon pattern; and

doping the first sub-region of the first polysilicon pattern, and the first sub-region and the second sub-region of the third polysilicon pattern with the P-type ions, to form a P-doped region of the PIN-type diode and a P-doped region of the P-type transistor.

11. The method according to claim 1 , wherein, after the step of forming the plurality of polysilicon patterns on the substrate, the method further comprises steps of:

forming a third photoresist layer covering the fourth polysilicon pattern; and

lightly doping the third polysilicon pattern and the first polysilicon pattern, to form a channel region of the P-type transistor having a threshold voltage and an I region of the PIN-type diode.

12. The method according to claim 1 , wherein, after the step of forming the plurality of polysilicon patterns on the substrate, the method further comprises steps of:

forming a fourth photoresist layer covering the first polysilicon pattern and the third polysilicon pattern; and

lightly doping the fourth polysilicon pattern, to form a channel region of the N-type transistor having a threshold voltage.