Glow-discharge treatments

Hoffman, A. S. Ioninzing Radiation and Gas Plasma (or Glow) Discharge Treatments for Preparation of Novel Polymeric Biomaterials. Vol. 57, pp. 141 — 157. 

Adhesion or printability of polymeric surfaces, including films, is often promoted by plasma or glow discharge treatment. In particular for apolar (low surface energy) surfaces such as polyolefins this is a commonly applied procedure. As a practical industrial example, the adhesion behaviour of polypropylenes after... 

Fig. 3. Schematic diagram of argon glow discharge treatment for the immobilization of surfactants (Reproduced with permission from Sheu et al., Contact angle, wettability and adhesion 531 Copyright (1993) VSP)...

In DC discharge for LCVD, the main core is the DG adhering to the cathode surface, and the anode is out of the onion structure in most cases. In DC discharge of Ar for glow discharge treatment or sputter deposition of the cathode material, the core is the IG, which does not touch the cathode surface. 

Table 6.1 Unpaired Spins Detected in Deposited Film and Substrate After Glow Discharge Treatments for 1 Hour or Less at 30 W Power... 

Components and /ijn (mtorr) of components Total /ijn (mtorr) Duration of glow discharge treatment (min) Yield of polymer film (mg/cm ) Spin concentration in polymer film [(spins/g) X 10 ] Linewidths of ESR first-derivative signal (G) Spins near surface of glass substrate [(spins/cm ) X 10 "] 5 = pjpra Pi (mtorr) Code on Fig. 6.10... 

Describing a sequential LCVD process, the first process is followed by the second process separated by / sign. For example, LCVD of CH4 is followed by glow discharge treatment of O2, and the sequential process is expressed by CH4/O2. If O2 is mixed with CH4, it is expressed by LCVD of (CH4-1-02) by placing the gas mixture in parentheses. 

MULTISTEP GLOW DISCHARGE TREATMENT OF POLYMER SURFACE... 

These findings clearly show that the principle of CAP also applies to glow discharge treatment, which is not intended to deposit plasma polymers, in a similar manner with respect to the interaction of luminous gas with materials. 

It is also important to note that the same glow discharge treatment could be achieved in the primary glow if the conditions are tailored for such a surface treatment by a very short exposure, e.g., a few seconds in contrast to a few hours of treatment time in the secondary plasma treatment. However, depending on the size and shape of substrate surface to be treated, a very short treatment is difficult to practice by a batch mode operation. This is where the merit of secondary plasma or remote plasma treatment is recognized. 

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