| AVS 60th International Symposium and Exhibition | |
| Surface Science | Tuesday Sessions |
| Session SS-TuP |
| Session: | Surface Science Poster Session |
| Presenter: | R. Tan, Kogakuin University, Japan |
| Authors: | R. Tan, Kogakuin University, Japan I. Takano, Kogakuin University, Japan |
| Correspondent: | Click to Email |
Recently, biodegradable resin attracts attention as one of the effective use of resources on environmental measures. PGA (Polyglycolic acid) used in this study is categorized to a kind of polyester resin and is composed of hydrogen, carbon and oxygen. PGA shows a high gas barrier property, a high hydrolysis property and high mechanical strength. These characteristics are applied for sutures of surgery or multi-layer PET bottles, while there is hardly application in an electronic field. The usage of PGA in electronic parts such as a printed circuit board has the important role in environmental measures, however, there are some problems that have to be overcome.
In this study, the surface of PGA was modified by using an ion beam so that the durability of the PGA coated with metal films was improved. The ion beam cut off the bonding of molecules and as a result the surface of PGA turned to a carbon layer which was stable against heating or humidity. Metal films of Ti or Cu were deposited on the modified PGA by vacuum evaporation. The ion beam irradiation and vacuum evaporation were performed using the high current ion implanter with an electron beam evaporator. The ion beam was extracted from the bucket type ion source with multi-aperture electrodes.
The Ar+ ion irradiation conditions were controlled at a current density of 20 μA/cm2, an acceleration voltage of 1 kV and irradiation time of 0-70 s. The deposition conditions of Ti and Cu were kept at deposition rate of 0.3 nm/s and a film thickness of 200 nm. The prepared samples were the metal coated PGA sample, the ion irradiated PGA sample and the metal coated sample on the irradiated PGA. The sample hardness was measured by a load-unloading method using micro-hardness tester with Knoop indenter. Friction coefficient and wear measurements were evaluated by reciprocating sliding test with load of 0.198N. The water contact angle was measured by using the θ/2 method. Electrical conductivity of metal films was calculated from V-I characteristics measured using the four probe method. Hydrolysis test was evaluated in a distilled water of 100 ml of 30℃. Surface chemical-bonding state was investigated by X-ray photoelectron spectroscopy.
Knoop hardness of Ti or Cu coated samples on the Ar+ ion irradiated PGA showed the maximum value around 50s in irradiation time. Mechanical properties of these samples were improved as compared with the metal coated PGA without Ar+ ion irradiation. The measurement results of electrical conductivity suggested the possibility of PGA used as a printed circuit board.