Method and system for temperature controlling in lithography process

A method comprising:

• placing a pellicle in a lithography system to cover a photomask;
• emitting a light to pass through the pellicle to the photomask, wherein the light is patterned by the photomask and then projects onto a semiconductor wafer;
• applying a test current to a membrane of the pellicle to obtain a temperature of the membrane during emitting the light;
• and
• applying a heating current to the membrane to heat the membrane, wherein a value of the heating current depends on the obtained temperature of the membrane.

A system comprising:

• a mask stage configured to secure a photomask;
• a pellicle positioned over the photomask, wherein the pellicle comprises:
• a membrane having an image region and a border region surrounding the image region;
• and
• conductive electrodes on the border region of the membrane and on opposite sides of the image region of the membrane;
• a substrate stage configured to secure a semiconductor wafer;
• a light source configured to emit a light to pass through the image region of the membrane of the pellicle to the photomask, the light being patterned by the photomask and then propagating to the semiconductor wafer;
• and
• a control device electrically connected to the conductive electrodes and configured to:
• applying a test current to the conductive electrodes to detect a temperature of the membrane;
• and
• applying a heating current to the conductive electrodes to heat the membrane.