System, ion implantation

Group III organometallics, gas-ohase decomposition of, 22 156 Group 3 (IIIB) perchlorates, 28 278 Group Ill-Sb system, ion implantation doping of, 22 187... 

B)-C-N system. Ion-implanted stable 30si isotopes were used as tracers, and secondary ion mass spectrometry was used for depth profiling. The experimentally determined diffusivities were lower by a factor of 10 for S13BC4 3N2 than for Si2.6C4.i N3 3 within the entire temperature range... 

Fig. 2. Schematic drawing of a conventional, directed beam ion implantation system (1).

Fig. 3. A typical design for a broad beam, B, ion implantation system.

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. 

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...

Aqueous Corrosion. Several studies have demonstrated that ion implantation may be used to modify either the local or generalized aqueous corrosion behavior of metals and alloys (119,121). In these early studies metallic systems have been doped with suitable elements in order to systematically modify the nature and rate of the anodic and/or cathodic half-ceU reactions which control the rate of corrosion. 

Ion Implantation Systems. An ion implantation system is used to accelerate ionized atomic or molecular species toward a target sample. The ionized species penetrates the surface of the sample with the resulting depth profile dependent on the implanted species mass, energy, and the sample target s tilt and rotation. An implanter s main components include an ionizer, mass separator, acceleration region, scanning system, and sample holder (168). 

Ion implantation has been successfully used to dope the IITSb material system. Sulfur has been used as an n-ty e dopant, although with poor activation efficiencies (175). -Type doping has been achieved using beryUium, zinc, and magnesium (175,176). Activation of the -type dopants is generally much better, near 50%. For the Sb-containing materials the post-implant anneal is conducted at much lower temperatures, typically <600° C. 

Another basic approach of CL analysis methods is that of the CL spectroscopy system (having no electron-beam scanning capability), which essentially consists of a high-vacuum chamber with optical ports and a port for an electron gun. Such a system is a relatively simple but powerful tool for the analysis of ion implantation-induced damage, depth distribution of defects, and interfaces in semiconductors. ... 

Susceptibility to radiation damage must be considered seriously if reference samples are to be calibrated for use in place of absolute systems. For the measurement of absolute C He, H) cross sections, films of polystyrene (CH) (which is relatively radiation hard) have been used successfiiUy, the RBS determination of carbon providing implied quantitation for the hydrogen present in the film. For a durable laboratory reference sample, however, there is much to recommend a known ion-implanted dose of H deep within Si or SiC, where the loss of hydrogen under room temperature irradiation will be neghgible. 

Recent applications of e-beam and HF-plasma SNMS have been published in the following areas aerosol particles [3.77], X-ray mirrors [3.78, 3.79], ceramics and hard coatings [3.80-3.84], glasses [3.85], interface reactions [3.86], ion implantations [3.87], molecular beam epitaxy (MBE) layers [3.88], multilayer systems [3.89], ohmic contacts [3.90], organic additives [3.91], perovskite-type and superconducting layers [3.92], steel [3.93, 3.94], surface deposition [3.95], sub-surface diffusion [3.96], sensors [3.97-3.99], soil [3.100], and thermal barrier coatings [3.101]. 

TOF-SIMS has important potentials in many areas of life science, in fundamental and applied research as well as in product development and control. This holds for the characterization of biological cells and tissues, of sensor and microplate arrays, of drug delivery systems, of implants, etc. In all these areas, relevant surfaces feature a very complex composition and structure, requiring the parallel detect ion of many different molecular species as well as metal and other elements, with high sensitivity and spatial resolution requirements, which are exactly met by TOF-SIMS. 

Table 1. Nanostructure of some investigated systems obtained by sequential ion implantation without subsequent annealing.

Figure 9. Comparison between a simulation based on the Mie theory of OD in the UV-Vis range for 3 nm clusters of pure Au, Ag, and Auo.4Ago.6 alloy in silica (a), with the experimental OD of the same systems in ion-implanted silica (b). (Reprinted from Ref [1], 2005, with permission from Italian Physical Society).

See also Ion beams Ion-cut process Ion implantation systems advantages and limitations of, 14 429 case hardening by, 16 208-209 channeling effect and, 14 435 in compound semiconductor processing, 22 185-188... 

Plasma fractionators, 12 130t Plasma immersion ion implantation (Pill) system, 14 427-428... 

Wafer contamination, in ion implantation systems, 14 445-446 WAG process, 13 626 Wait and see problems, 26 1025, 1028 Wakamatsu reaction, 2 573 Wakame... 

Ion Beams. Several investigations have been made on the effects of ion beam irradiation on simple chemical systems. Polymers have also been irradiated with ion beams as an extension of studies on the ion implantation of other materials. To date, most of these studies have been concerned with gross effects, sometimes through to carbonisation (70) but here is a field which could have an industrial potential. 

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