Plasma cleaner

SF6 glass prisms were thoroughly cleaned, rinsed with organic solvents, treated in a plasma cleaner and, subsequently, heated in a vacuum chamber to a temperature of approx. 100 °C. A 50 nm gold film was deposited. During deposition the vacuum chamber was evacuated to 10-3 Pa. The thickness of the metal layer on the prism was con-... 

Smooth plates of silver (1.0-mm thick, 99.9% purity), as supplied by Aldrich, were first treated with a plasma cleaner (Mod. PDC-32G, Harrick Sc. Co., NY, USA)... 

Thin films of PEO can be prepared by spin coating filtered (mesh size ca. 0.2 pm) solutions of PEO in chloroform onto precleaned silicon wafers or glass cover slips using a conventional spin-coater (typical concentrations of 1.0-20.0 mg/ml and typical spinning speeds of 2,000-3,000 rpm for 1 min are recommended for film thicknesses between ca. 15 and 300 nm). The cleaning of silicon wafers can be carried out in a plasma cleaner or using oxidizing solutions [59]. The films should be dried for at least 24 h in vacuum to remove residual solvent. 

Microwave induced plasma was generated by a Harrick Plasma Cleaner/ Sterilizer PDG-32G. The operating pressure was achieved by a vacuum pump (Vacuubrand RD 4). Hydrogen was applied as a permanent stream, regulated by the integrated inlet valve and adjusted to approx. 0.7 mbar (determined by a MKS PDR 2000 Dual Capacitance Manometer). The gas flow was not determined. 

Place the molded piece of PDMS and a new, clean, and dry cover slip in the glass cavity of the plasma cleaner see Note... 

Do not touch the surfaces that will be assembled later, not even with gloves. Load the PDMS with the molded surface pointing upward and remove the tape inside the plasma cleaner cavity. Close the plasma cleaner. 

Evacuate the plasma cleaner. After about 1 min, turn on the radio frequency. A blue/violet plasma should be visible inside the cavity of the plasma cleaner (if not, evacuate longer). 

Carefully let some air leak into the plasma cleaner via the needle valve in the door until the color of the plasma has changed to deep pink. Operate under these conditions for about 3 min, then turn off. 

Plasma-cleaning equipment range from small laboratory models having 6-inch-diameter chambers to large-capacity automatic production units. Equipment from March Instruments (a Nordson Co.) is reported to enable a user to process 500-1,000 leadframes per hour. Table 4.11 provides further detail for some commercially available plasma cleaners. 

Each PDMS mold is then treated with a plasma cleaner for 20 s and placed on a number 1 24 mm X 50 mm glass coversUp. 

The bonded device is treated again with the plasma cleaner for 15 s to facilitate filling with liquid. 

Plasma cleaner (Fiarrick Scientific Corporation, Ossining, NY)... 

All the instrumental parts that are expected to be coated with the polymer, including the waveguides for the OWFS and the balls/disks of all tribological instruments, were oxygen-plasma cleaned for ca. 2 min in a Harrick Plasma Cleaner/Sterilizer PDC-32G... 

All the instrumental parts that are expected to be in contact with the polymer solution, including the balls and disks of all tribological instruments, were oxygen-plasma cleaned for ca. 2 min in a Harrick Plasma Cleaner/Sterilizer PDC-32G instrument (Ossining, NY, USA) prior to the measurements. Before the plasma cleaning, the instrumental parts and the tribo-pair of ultra-thin-film interferometry and MTM were degreased by sonication in toluene for 10 min, followed by sonication in isopropanol for 10 min, and dried in nitrogen atmosphere. The pins, disks and assembly parts... 

In most cases, the hydrophilization of the tribopair was achieved by means of oxygen-plasma-treatment for 1 min in a Harrick Plasma Cleaner/Sterilizer PDC-32G instmment (Ossining, NY, USA). Following oxygen-plasma-treatment, the water-contact angle of the PDMS surface (ox-PDMS) was measured to be lower than 3°. The static water contact angles ( + 2°) for PP and PA-6,6 disk surfaces before (and after) oxygen-plasma-treatment were 107 (48°) and 82 (20°), respectively. 

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