Method of fabricating array substrate using dry etching process of silicon nitride

摘要

A method of fabricating an array substrate includes: forming a line or an electrode on a substrate on which a pixel region is defined, forming a protection layer on the line or the electrode, the protection layer formed of silicon nitride (SiNX), forming photoresist patterns on the protection layer, and loading the substrate having the photoresist pattern into a chamber of a dry etching apparatus, and performing a first dry etching process on the protection layer exposed between the photoresist patterns using a first gas mixture containing nitrogen trifluoride (NF3) gas to form a contact hole exposing the line or the electrode.

主权项

1. A method of fabricating an array substrate, comprising:
forming a line or an electrode on a substrate on which a pixel region is defined; forming a protection layer on the line or the electrode, the protection layer formed of silicon nitride (SiNX); forming photoresist patterns on the protection layer; loading the substrate having the photoresist patterns into a chamber of a dry etching apparatus, and performing a first dry etching process on the protection layer exposed between the photoresist patterns using a first gas mixture containing helium (He), nitrogen trifluoride (NF3), and oxygen (O2), a ratio of nondimensional flow rates of which ranges from 1:1.15:2.875 to 1:1.2:3.6, or 1:1.15:3.6 to 1:1.2:4.5, to form a contact hole exposing the line or the electrode, wherein the nondimensional ratio of the flow rates is defined as a ratio of the flow rate of the helium, the nitrogen trifluoride, and the oxygen per unit time to the ratio of the helium per unit time as expressed in sccm; and performing a second dry etching process for a second amount of time by replacing the first gas mixture with a second gas mixture containing nitrogen trifluoride (NF3) and oxygen (O2) without helium (He) after performing the first dry etching process for a first amount of time; and performing a third dry etching process for a third amount of time by replacing the second gas mixture with the first gas mixture after performing the second dry etching process, wherein the first, second, and third dry etching processes prevent a drop in etch rate of the protection layer over time, and wherein the flow rate of the helium during the first and third dry etching processes ranges from about 145 sccm to about 155 sccm.