A third generation plasma immersion ion implanter dedicated to biomedical materials and research has been designed and constructed. The distinct improvement over first and second generation multipurpose plasma immersion ion implantation equipment is that hybrid and combination techniques utilizing metal and gas plasmas, sputter deposition, and ion beam enhanced deposition can be effectively conducted in the same machine. The machine consists of four sets of high-efficiency metal arc plasma sources with magnetic filters, a custom designed high voltage modulator for operation up to 60 kV, a separate high-frequency, low-voltage power supply for hybrid treatment processes, special rotating sample stage for samples with an irregular shape, and other advanced features. The machine has been installed at Southwest Jiaotong University and operated reliably for 6 months. This article describes the design principles and performances of the machine as well as pertinent biomedical applications.

We propose a method to improve the impact energy of ions implanted into the interior sidewalls of cylindrical specimens during plasma immersion ion implantation. Our idea is based on a zero potential conductive auxiliary electrode positioned at the axis of the implanted cylindrical bore. We calculate the structure of the ion-matrix sheath in an infinitely long cylindrical bore with an auxiliary electrode and analyze the dependence of the radius of the auxiliary electrode on the electric field in the bore. Our results show that the auxiliary electrode improves significantly the distributions of the potential and the electric field inside the cylindrical bore. In addition, because the auxiliary electrode improves the potential drop from axis to sidewalls of the bore and introduces an electric field component which does not vary when the ions are implanted into the sidewalls, the impact energy can be improved in a cylindrical bore during plasma immersion ion implantation.

A new generation multipurpose plasma immersion ion implanter ͑PIII͒ was custom designed, constructed, and installed in the City University of Hong Kong. The system is designed for general R&D applications in metallurgy, tribology, surface modification, and fabrication of novel materials. Using the new rf ion source in conjunction with the internal antenna system, the plasma density achieves excellent uniformity both laterally and axially. The system also incorporates two metal sources, including four metal arc sources and a sputtering electrode, so that multiple metal deposition and implantation steps can be performed in succession in the same equipment without exposing the samples to air. This capability can be critical to the study of surface properties and corrosion resistance. This article describes the design objectives, the novel features, and the characteristics of this new generation PIII equipment.

The fourth-generation plasma immersion ion implantation and deposition (PIIID) facility for hybrid and batch treatment was built in our laboratory recently. Comparing with our previous PIIID facilities, several novel designs are utilized. Two multicathode pulsed cathodic arc plasma sources are fixed on the chamber wall symmetrically, which can increase the steady working time from 6 h (the single cathode source in our previous facilities) to about 18 h. Meanwhile, the inner diameter of the pulsed cathodic arc plasma source is increased from the previous 80 to 209 mm, thus, large area metal plasma can be obtained by the source. Instead of the simple sample holder in our previous facility, a complex revolution-rotation sample holder composed of 24 shafts, which can rotate around its axis and adjust its position through revolving around the center axis of the vacuum chamber, is fixed in the center of the vacuum chamber. In addition, one magnetron sputtering source is set on the chamber wall instead of the top cover in the previous facility. Because of the above characteristic, the PIIID hybrid process involving ion implantation, vacuum arc, and magnetron sputtering deposition can be acquired without breaking vacuum. In addition, the PIIID batch treatment of cylinderlike components can be finished by installing these components on the rotating shafts on the sample holder.