Method of manufacturing image sensor
View Patent ↗A method of manufacturing an image sensor, which avoids corroding a pad electrode with overexposure to corrosive chemicals, includes forming a pad electrode over a semiconductor substrate, forming a passivation layer over the pad electrode, applying a photoresist over the passivation layer, etching the photoresist and passivation layer to form a via hole exposing the pad electrode, and applying an amine based chemical for a predetermined, limited time to remove the photoresist. Alternatively, an amide based chemical which does not corrode the pad electrode can be substituted for the amine based chemical.
1. A method of manufacturing an image sensor comprising:
forming a pad electrode above a semiconductor substrate;
forming a passivation layer over the pad electrode;
applying a photoresist over the passivation layer;
etching the photoresist and passivation layer to form a via hole exposing the pad electrode; and
applying an amine based chemical to remove the photoresist, wherein the chemical comprises N,N-bis(92-hydroxyethyl)-N-cyclohexylamine.
2. The method of claim 1 , wherein the amine based chemical is applied for a duration between 270 to 330 seconds.
3. The method of claim 1 , wherein the amine based chemical is applied by spraying.
4. A method of manufacturing an image sensor comprising:
preparing a semiconductor substrate having a pixel array section and a logic circuit section;
forming a pad electrode in the logic circuit section;
forming a passivation layer over a top surface of the semiconductor substrate;
applying a photoresist over the passivation layer;
patterning the photoresist using a photo-etching process to remove the passivation layer over the pad electrode, thereby forming a via hole exposing the pad electrode;
applying a color photoresist over the passivation layer in the pixel array section, and patterning the color photoresist to form a color filter layer;
spraying an amine based chemical to remove the color photoresist, wherein the chemical includes N,N-bis(92-hydroxyethyl)-N-cyclohexylamine;
reworking the color photoresist over the passivation layer in the pixel array section;
forming a planarizing layer over the color filter layer; and
forming micro-lenses over the planarizing layer.
5. The method of claim 4 , wherein the photoresist is removed by spraying the amine based chemical for a time from 270 to 330 seconds.
6. The method of claim 4 , the color photoresist is removed by spraying the amine based chemical for a time from 270 to 330 seconds.
7. The method of claim 4 , wherein the passivation layer includes an oxide layer.
8. The method of claim 4 , wherein the pad electrode is formed by depositing a metallic material by sputtering, depositing a silicon nitride material, and patterning the deposited material.
9. The method of claim 4 , wherein the micro-lenses are formed by applying another photoresist layer, patterning the photoresist layer using a defocus technique, and reflowing the patterned photoresist.
10. A method of manufacturing an image sensor comprising:
preparing a semiconductor substrate having a pixel array section and a logic circuit section;
forming a pad electrode in the logic circuit section;
forming a passivation layer over a top surface of the semiconductor substrate;
applying a photoresist layer over the passivation layer;
patterning the photoresist layer using a photo-etching process to remove the passivation layer over the pad electrode, and forming a via hole exposing the pad electrode;
applying a color photoresist over the passivation layer in the pixel array section, and patterning the color photoresist to form a color filter layer;
spraying N,N-dimethyl acetamide to remove the color photoresist;
reworking the color photoresist over the passivation layer in the pixel array section;
forming a planarizing layer over the color filter layer; and
forming micro-lenses over the planarizing layer.