Back-channel-etched tft substrate and manufacturing method thereof

A manufacturing method of back-channel-etched (BCE) thin film transistor (TFT) substrate, comprising:

• providing a base substrate, forming a gate on the base substrate, forming a gate insulating layer on the gate and the base substrate;
• forming a C-axis crystallized IGZO thin film on the gate insulating layer, patternizing the C-axis crystallized IGZO thin film to obtain an active layer;
• forming a source and a drain separated with interval on the active layer;
• wherein the C-axis crystallized IGZO thin film is formed on the gate insulating layer by using a sputtering process in a predetermined atmosphere including a gas that is a mixture of oxygen and argon to deposit an amorphous IGZO thin film on the gate insulating layer, followed by annealing of the amorphous IGZO thin film to obtain the C-axis crystallized IGZO thin film, wherein a volume percentage of oxygen in the gas of the mixture of oxygen and argon is greater than 40%;
• wherein the sputtering process comprises a magnetron sputtering process, and oxide in the amorphous IGZO thin film deposited with the sputtering process is In:Ga:Zn:O=1:1:1:X, where X is greater than 4;
• wherein the molar ratio of indium, gallium, zinc, and oxide in the C-axis crystallized IGZO thin film beings In:Ga:Zn:O=1:1:1:X, where X being greater than 4;
• wherein the annealing temperature of the annealing process on the amorphous IGZO thin film being less than or equal to 600° C.;
• wherein the material of the source and the drain comprising copper.