Etching in oxygen plasma

Reactive ion etching in oxygen plasma results In controllable nano-pillar formation... 

Another lamination approach is the bonding of a film of thermoplastic liquid crystal polymer (LCP) to glass. The LCP layer can be structured with microchannels dry etched in oxygen plasma using an aluminum mask. After removal of the aluminum mask, the LCP can be laminated onto glass, silicon, or a metal under pressures at temperatures around 260-270 °C [9]. Again, the temperature is too high for biomolecule pre-deposition. 

Another way of UV patterning is the coating of a dry film of responsive polymer with a photoresist. Resist lithography and dry etching in oxygen plasma yield hydrogel patterns down to 2.5 pm, see Figure 14. ... 

The etch resistance of poly (butene-1 sulfone) in fluorocarbon-based plasmas can be enhanced by prior treatment of the surface in an oxygen plasma. This pretreatment inhibits or retards the depolymerization reaction that characterizes normal etching in fluorocarbon plasmas, thereby permitting formation of a surface-modified layer which exhibits a substantially reduced etch rate. Pretreating PBS in an oxygen plasma enables it to be used subsequently in selective reactive-ion etch processes involving fluorocarbon plasmas to delineate submicron, anisotropically etched patterns. 

PBS/SUBSTRATE ETCHING IN FLUOROCARBON PLASMAS WITH PRIOR OXYGEN EXPOSURE... 

Further studies have shown, however, that under appropriately chosen plasma etching conditions, poly(alkenylsilane sulfone)s can be passivated in an oxygen plasma like other organosilicon polymers (72,73), but the passivation process depends strongly on the plasma processing parameters. In this paper, we report the results of our studies on the degradation and passivation processes of a typical poly(alkenylsilane sulfone), viz., poly(3-butenyltrimethylsilane sulfone) (PBTMSS) (13) in oxygen plasmas. 

It is well known that insertion of silicon-containing groups into a polymer enhances its plasma resistance greatly. The rate of a reactive ion etching in oxygen (RIE in O2) in the stationary state, P, is proportional to the ratio of the silicon atom mass densities in the polymer, ppoi., and in Si02, Poxide ... 

Many attempts have been made to find correlations between etch resistance of a polymer and its chemical nature. The thumb rule advices to use aromatic groups incorporated into a polymer to enhance etch resistance. However, about 20 years ago it was found that aromatic rings were not strictly needed to improve polymer etch resistance. It was the carbon-to-hydrogen atoms ratio for a polymer that was related to its resistance in oxygen plasma. An increase in the ratio tends to produce a decreased rate of the RIE in O2. 

Plasma Etching. The glow discharge reactor used in oxygen plasma etching of POP film was described previously ( ). The reactor pressure was monitored with a capacitance manometer (MKS... 

Finally silicon can be etched in fluorocarbon plasmas (e.g., CF4). The addition of oxidation (oxygen) or reducing (hydrogen) agents to these plasmas has been used to control polymer formation and thereby affect the etch rate and selectivity. Fig. 43... 

Khulbe and Matsuura characterized the dense PPO membrane etched by oxygen plasma [54] and studied the structural changes in the depth direction by AFM. Carbon disulfide was used as a solvent when the dense membrane was prepared. It should be recalled that unhke other solvents, carbon disulfide produced a dense PPO membrane, and supernodular aggregates could be observed on its surface. 

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