Optical lithography is the process of creating specific patterns on semiconductor wafers using a photosensitive material (known as photoresist, PR) and an ultraviolet light exposure system to transfer patterns from masks to wafers. According to pattern shape we will offer positive or negative photoresist.
Steps Used in Photolithography
• Surface cleaning
• Barrier layer formation (Oxidation)
• Spin coating with photoresist
• Soft baking
• Mask alignment
• Exposure
• Development
• Hard baking
• Post process cleaning