How do I Remove Gum After Ion Implantation?

How do I Remove Gum After Ion Implantation?

What is the role of ion implantation in the IC process?

Ion implantation is mainly the formation of traps(WELL), low-doped deport(LDD), and heavily doped regions (P+/N+).

2. Why is photoresist difficult to remove after ion implantation?

During ion implantation, the photoresist is bombarded with high-energy ions, whose energy can break the chemical bonds in the molecular chain of the photoresist, causing these molecules to be cross-linked to form a more stable chemical structure. This cross-linking results in a hard crust on the surface of the photoresist, which makes it more difficult to remove.
3. What are some of the most effective methods for removing glue?
The method of O2 plasma ashing and wet combination is adopted. The surface of the photoresist hard shell can be bombarded with O2 plasma to expose the "fresh" photoresist, and then the photoresist and the resulting particles can be removed with SPM and RCA.

SPM：concentrated sulfuric acid + hydrogen peroxide; RCA1: ammonia + hydrogen peroxide; RCA2: hydrochloric acid + hydrogen peroxide

Of course, it can also be cleaned with ozone water.

However, O2 plasm will cause a small amount of damage to the silicon on the surface of the chip, and the loss of silicon is not considered in the low-end process (node < 65nm). When the high-end process is made, it needs to be removed completely using the wet process.

END