Plasma Bonding

Another direction is the development of photostructurable polysiloxane grades (PDMS-like materials structured by photolithography like photoresists). These materials could be used instead of gaskets with much better and easier alignment for clamping or perhaps for direct plasma bonding to glass chips. 

MicroChannel glow discharge MicroChannel surface modification MicroChannel surface sterilization Plasma bonding... 

In brief, the upper and lower microfluidic channels are respectively constructed in the top and the bottom silicone substrates, using standard soft lithography techniques. Then a number of inlets and outlets are punched. A blank middle silicone rubber slab is also prepared. The microstructured top elastomer layer is bonded to the blank silicone substrate using thermal or plasma bonding, and addition inlets are punched on the bonded elastomer sheet. The bottom silicone elastomer is bonded... 

C. A. L. Westerdahl and co- oSk.cx.s Activated Gas Plasma SuTpace Treatment of Polymers for Adhesive Bonding, Part III, Technical Report 4279, Picatinny Arsenal, Dover, N.J., 1972. 

The existence of the XeCHg [34176-86-8] cation has been estabtished ia the gas phase. The Xe—C bond energy of the XeCHg cation has been estimated to be 180 A 33 kJ/mol (112) and more recently, 231 A 10 kJ/mol (113) by ion cyclotron resonance. The compound Xe(CF3)2 [72599-34-9] is reported to be a waxy white sotid having a half-life of ca 30 min at room temperature (114). The synthesis iavolved the addition of XeF2 to a tritiuoromethyl plasma, but the characterization of this compound is limited and has not been iadependently confirmed. 

Chemical removal of surface material is produced through standard bond-breaking reactions. Typically chlorofluorocarbons (CECs) have been used, eg, CECl, CE2CI2, CE Cl, CE4, CHE, C2C1E. Eor example, CE dissociates into E atoms and fluorinated fragments of CE in a plasma ... 

In most cases, CVD reactions are activated thermally, but in some cases, notably in exothermic chemical transport reactions, the substrate temperature is held below that of the feed material to obtain deposition. Other means of activation are available (7), eg, deposition at lower substrate temperatures is obtained by electric-discharge plasma activation. In some cases, unique materials are produced by plasma-assisted CVD (PACVD), such as amorphous siHcon from silane where 10—35 mol % hydrogen remains bonded in the soHd deposit. Except for the problem of large amounts of energy consumption in its formation, this material is of interest for thin-film solar cells. Passivating films of Si02 or Si02 Si N deposited by PACVD are of interest in the semiconductor industry (see Semiconductors). 

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