Rf glow discharge

The depth of the crater can also be measured from the radiation leaving from the glow discharge emission source in the case of transparent samples ablated by RF glow discharges (see Section 5.6.4). Indeed, part of the emitted light is reflected at the sample surface and modulates the line intensity, and in the case of transparent layers a technique based on the interference patterns has been developed for measuring layer thicknesses [562]. 

Electrically non-conducting powders These can also be analyzed after mixing with Cu powder and briquetting into pellets, as first shown by El Alfy et al. [243] for geological samples and ores. The performance depends greatly on the particle size of the powders, but detection limits in the gg/g range are possible for the light elements (Al, Be, B.). 

Extensive measurements of electrical characteristics and plasma parameters for RF glow discharges have been performed by Marcus et al. [565], e.g. with Langmuir probes, and they revealed higher electron number densities than in DC glow discharges. However, comparisons are difficult because of constructional dif- 

---

Hot RF and - DC plasma, are discharge, plasma jets Oxy-acetylene flames Low pressure microwave plasma, holt filament. Low pressure DC or RF glow discharge Thermal decomposition... 

Fig. 4.37. Depth (temporal) profile obtained on a multilayer coating produced by plasma vapor deposition (PVD) using optimized rf-glow discharge conditions. Layer thickness ...

In the early 1970s, Spear and coworkers (Spear, 1974 Le Comber et al., 1974), although unaware of the presence of hydrogen, demonstrated a substantial reduction in the density of gap states (with a corresponding improvement in the electronic transport properties) in amorphous silicon films that were deposited from the decomposition of silane (SiH4) in an rf glow discharge. 

Figure 16 (Street et al., 1986) shows the typical sample structure, consisting of three layers of a-Si H. Results using this technique have been reported for samples grown by the rf glow discharge of silane and by rf sputtering (Shinar et al., 1989). The first layer is hydrogenated amorphous silicon, deposited under conditions that yield high quality films (i.e., deposition temperature of 230°C, low growth rate) and is typically two microns thick. Next a layer of approximately 1000 A is deposited, whereby...

Fig. 3. Formation of a pulsating negative sheath on a capacitively coupled surface in an rf glow discharge [after Butler and Kino ] a) initial application of rf voltage b) steady-state application of rf voltage...

Polymer film RF glow discharge in 100watts0.15 torr ([FJ... 

Figure 5.29 Instrumental setup of a radiofrequency (rf) glow discharge mass spectrometer by combining an ion source developed in house with a commercial double-focusing sector field mass spectrometer with reverse Nier-Johnson geometry (Element, Thermo Fisher Scientific, Bremen, Germany), (f S. Becker et al., IntJ. Mass Spectrom., 164, 81 (1997). Produced by permission of Elsevier.)...

Figure 6.7 Part of a mass spectrum for silicon determination at m/z = 28 in high purity GaAs measured by rf GDMS (Element, Thermo with rf glow discharge ion source constructed in our lab). The interfering polyatomic ions 12CuO+ and UN2+ are well separated at mass resolution m/Am of 3000. (J. S. Becker et ai, Int. J. Mass Spectrom. 164, 81 (1995). Reproduced by permission of Elsevier.)...

In thin-film processes for the fabrication of electronic materials and devices, rf glow discharges are primarily used. The application of an rf voltage at frequencies between 50 kHz and 40 MHz to a low-pressure (6-600 Pa) gas results in a chemically unique environment (Table I.)... 

Table I. Properties of rf Glow Discharges (Plasmas) Used for Thin-Film Etching and Deposition...

Table V, Summary of Conducting Films Deposited in rf Glow Discharges ...

Plasma CVD has been used since the middle of the 1970s. For the creation of the plasma, DC glow discharge [224], RF glow discharge [219, 225-227], microwave plasma [228, 229], or plasma jets [230] are used. 

Clearly, there are many approximations in this model, so close agreement with experimental data should not be expected. It is interesting, however, to consider some relevant experimental data.17 In these experiments, peak-to-peak and DC bias voltages were measured for a 13.56-MHZ RF glow discharge confined within a reactor chamber with two electrodes of unequal area. Using a... 

---