Photoresist
Photoresist Photoresist
Polymers are formed by linking together many smaller repeating units called monomers; many are C-based. One of the simplest is: polyethylene Monomer: Ethylene: C 2 H 4 Polymers can be linear or branched Branching, cross-linking increases strength and density Positive Tone resist: if exposure leads to breaking polymer chains, the polymer dissolves easily in developer Negative Tone resist: if exposure leads to cross linking, polymer dissolves slowly in developer Figure 8.3 (A) Polyethylene, an example of a simple polymer. (B) Branched-chain polymers. (C) Cross-linking.
Positive resist In i-line and g-line exposures, a class of compounds, DQN DQ: diazoquinone is the PAC and the resin material is Novolac (benzene ring with substituted methyl and OH groups) -evolved from materials to make blueprints Solvents added to adjust viscosity, much of this evaporates before the exposure is done Figure 8.4 Meta-Cresol novolac, a commonly used resin material in g- and i-line applications. The basic ring structure may be repeated from 5 to 200 times. Figure 8.5 Diazo quinone (DQ), the most commonly used photoactive compound for g- and i-line applications. The right-hand ring is not an aromatic but has a double bond.
- Page 1 and 2: Chapter 8 Photoresists
- Page 3 and 4: Photoresists (PR) or resists Three
- Page 5: Substitute: Methyl group Chlorine A
- Page 9 and 10: Light, water are the main drivers o
- Page 11 and 12: Contrast, γ , is the slope of the
- Page 13 and 14: Figure 8.9 Typical process flow in
- Page 15 and 16: Industrial systems are called “co
- Page 17: Exposing resist over topology cause
Polymers are formed by linking together<br />
many smaller repeating units called<br />
monomers; many are C-based. One of<br />
the simplest is: polyethylene<br />
Monomer: Ethylene: C 2 H 4<br />
Polymers can be linear or branched<br />
Branching, cross-linking increases<br />
strength and density<br />
Positive Tone resist: if exposure leads to<br />
breaking polymer chains, the polymer<br />
dissolves easily in developer<br />
Negative Tone resist: if exposure leads to<br />
cross linking, polymer dissolves slowly in<br />
developer<br />
Figure 8.3 (A) Polyethylene, an<br />
example of a simple polymer. (B)<br />
Branched-chain polymers. (C)<br />
Cross-linking.
Change language