Plasma source ion implantation

Fig. 4. A schematic of the plasma source ion implantation system, a plasma source chamber linked to a high voltage pulser. The plasma can be created from...

A novel organic (chitosan) and inorganic (tetraethyl orthosilicate) composite membrane has been prepared, which is pH sensitive and drug permeable [258]. The latter possibly involved in ionic interactions. By plasma source ion implantation technique, the adhesion between linear low-density polyethylene and chitosan could be improved [259]. Such bilayer films showed 10 times lower oxygen permeability, a property of use in food packaging applications. These multilayer films were easily recyclable. 

The ion beam applications presented later in this chapter are basically related to (conventional) ion implantation and PHI (alternatively known as plasma source ion implantation or PSII). 

Using carbon ions, this technique has been used to carburize a substrate surface prior to deposition of a hard coating. The process is similar to ionitriding, where the reaction in-depth depends on thermal diffusion. In plasma source ion implantation (PSII), the plasma is formed in a separate plasma source and a pulsed negative bias attracts the ions from the plasma to bombard and heat the surface. 

The disadvantage of ion implantation is that the ion beam runs straight in ordinary processing, so it is inefficient to apply to objects with curved surfaces or complex shapes, even by combining rotation or use of multi-ion sources. However, it is noteworthy that plasma-based ion implantation (Zhu et al, 2002) was tried and F ions were implanted to a model turbocharger wheel. The oxidation resistance obtained was the same as that for the flat plate of the same material. Research is being carried out to apply this method to metal ions. 

The plasma source implantation system does not use the extraction and acceleration scheme found in traditional mass-analy2ing implanters, but rather the sample to be implanted is placed inside a plasma (Fig. 4). This ion implantation scheme evolved from work on controlled fusion devices. The sample is repetitively pulsed at high negative voltages (around 100 kV) to envelope the surface with a flux of energetic plasma ions. Because the plasma surrounds the sample, and because the ions are accelerated normal to the sample surface, plasma-source implantation occurs over the entire surface, thereby eliminating the need to manipulate nonplanar samples in front of the ion beam. In this article, ion implantation systems that implant all surfaces simultaneously are referred to as omnidirectional systems. 

Ion Implantation- these plasma machines are used to form the various parts of the coupled transistors at voltages of 5 kV to 2 MV. These include retrograde well formation, gates, drains and sources. 

Modified PTFE surfaces show a high degree of biocompatibility with good cell adhesion and proliferation [7-11], However, the UV-treatment results also in a loss of mechanical stability due to the scission of polymer chains, especially for light-sources with wavelengths below 193 nm [6], Similarly to the ion implantation or plasma modification, also the UV light-irradiation is performed on both sides of a polymer foils in order to avoid the material torsion. 

As a boron nitride film, a B-C-N passivation film can also be deposited by plasma-enhanced CVD in semiconductor devices [9], and hydrogenated boron nitride carbide films are applied for X-ray mask membranes. The radiofrequency (13.56 MHz) plasma-enhanced CVD process uses B2H6, CH4, and Ng or NH3 as source gases, or in a sputtering process with a boron target, CH4, N2, and Ar are used [10 to 18]. A B-C-N mixed phase can also be prepared by N" ion implantation into B4C at 100 keV [19]. 

All chemicals and radiation sources need to be identified during the exposure assessment. Some semiconductor manufacturing operations involve reaction products that are formed by the process (e.g., plasma systems and ion implanters). When the composition of the reaction products is uncertain, bulk samples are taken and analyzed for specific compounds identified in previous surveys and then for unknowns. Data from the bulk samples are used to determine if subsequent personal breathing zone samples are needed. 

Figure 4.21 from reference [14] illustrates depth profiles of a 500 eV P implant in Si using Cs" (with 02 oxygen leak) and 02 primary beams with 150 eV impact energy. The instmment was a Cameca IMS Wf equipped with an rf plasma-type ion source for the 02 beam and a Cs" source with a modified ion extraction system. The SIMS profiles have been compared to HR-RBS data. The depth scale was based on the HR-RBS data and the 2 profile is the best fit to the HR-RBS profile. 

Liao JD, Chen HJ, Chang CW, Chiu SM, Chen ZS. (2006) Thin-film photo-catalytic Ti02 phase prepared by magnetron sputtering deposition, plasma ion implantation and metal vapor vacuum arc source. Thin Solid Films 515 176-185. 

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