Etching plasma-etched surface

Some of the modern surface analysis methods have been used to study the surface chemistry of both plasma etched surfaces and plasma polymerized thin films. Much of this work has involved exposure of these surfaces to air as the samples are transferred from the plasma system to the surface analysis system. However, in a few cases surface analysis has been performed in the plasma system after the plasma gas has been pumped away. This work will be discussed in more detail later in this chapter. 

Low energy electron-enhanced etching (LE4) uses a DC plasma in which electrons with energies <15 eV and reactive species at thermal velocities are incident on a sample. The sample is also heated at temperatures ranging from 50 to 250°C. Gillis et al [26,27] used hydrogen and chlorine plasmas to produce highly anisotropic etch profiles and smooth etch surfaces, at etch rates of 50 - 70 nm/min. 

Plasma treatment is widely used commercially for polymer surface modification. Plasma discharge treatments are used to improve adhesiveness and printing properties, to improve cell adhesion to tissue culture substrates (1 ) and to etch or clean the surfaces of materials (removal of photoresist materials on semiconductors, for example ( ). The surface characterization of plasma-modified surfaces is important in order to provide greater insight into how the properties are changed. 

Kajimura, N., Harada, Y. and Usukura, J. (2000) High-resolution freeze-etching replica images of the disk and the plasma membrane surfaces in purified bovine rod outer segments. J. Electron Microsc. 49,... 

In the case of the n-heptyl viologen deposition, nucleation rates of the first molecular layers of this molecule control the deposition rates of subsequent layers. The nucleation reaction follows the instantaneous nucleation model — and is found to be highly sensitive to the chemical and physical nature of the electrode surface prior to deposition. RF-plasma of ion-beam etched surfaces generally show greatly enhanced nucleation and bulk deposition rates. 

All three cases mentioned earlier (plasma etching, plasma polymerization, surface modification) have a number of important applications related to organic materials in general and polymers in particular. 

Keywords adhesion, adhesive bonding, surface treatment, corona treatment, flame treatment, chemical etching, surface tension, plasma treatment, pressure-sensitive adhesive, adhesive bond strength, adhesive bond durability. 

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