Hardware interview practice
Order the Main Photolithography Steps
A wafer has a prepared film that must receive a patterned etch mask using a positive photoresist process. Which simplified process order and limitation are correct?
Choose one
Answer choices
- A. Develop before exposure so the mask can directly fill the removed resist with transistor material.
- B. Feature size is determined only by the marketing node name and is independent of focus, overlay, optics, resist, and process control.
- C. Coat resist, soft-bake, align and expose, post-exposure-bake as required, develop the soluble exposed regions, transfer the pattern into the film, then strip resist; resolution and yield depend on wavelength, numerical aperture, process factor, focus, overlay, resist behavior, and defects.
- D. Etch the unpatterned wafer first, then apply resist and expose it only to measure whether the completed pattern was correct.