Glass fusion bonding

Thermal bonding of glass is similar to direct bonding of silicon. A distinction is made between two methods with and without plastic deformation. For extremely 

The degree to which the whole component is deformed after bonding depends on the quality of the surface. 

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The mixer was made by wet-chemical etching of glass substrates, following a photolithographic step, yielding channels for the fluid flow and for the electrodes. The electrodes (100 Q resistors) were made by an electron-beam evaporation process generating thin metallic films in the etched channels [92], Holes were drilled into the cover plate for inlet and outlet connection. Fusion bonding was used to seal the plates. 

In micromachines, alignment is often even more complex than in IC manufacture. Indeed one not only deals with high-aspect-ratio 3D features, but often needs to align the 3D features on both sides of the wafer, as in the case of wafer to wafer (fusion bonding) [4] or wafer to glass bonding (anodic bonding)... 

Obeid and coworkers [128] reported a microsystem fabricated on two glass plates (each 40 x 45 x 0.55 mm), where a continuous channel network was etched into the bottom plate by standard photolithography and wet chemical etching, followed by thermal fusion-bonding of the two plates to form a closed stmcture. This system (see Fig. 14a) used a continuous flow concept to demonstrate functional integration of reverse transcription (RT) and PCR (RT-PCR) with operator selection of the number of amplification cycles to secure the results shown in Fig. 14b. The RT phase of the measurement involved the synthesis of DNA using mRNA templates and was performed before DNA amplification to allow quantification of mRNAs. The integration of RT and PCR processes within a monolithic chip is often problematic as RT components can interfere with the subsequent PCR... 

In recent times, commodity thermoplastics have become signiflcant contenders as matrices for glass fibre composites where environmental resistance is sought for example, polypropylene is now available in a pre-preg form for fusion bonding. Since it has low polarity and is also partially crystalline, moisture absorption is very low. 

Chem. Descrip. High m.w. polyamide/polyester copolymers Uses Hot-melt adhesive for extrusion of fusible film, monofilament, netting, web, and multifilament, for thin film fusible coatings, for applic. by disp. techniques used in textile industry, adhesive for fusion bonding of textiles, leather, wood, glass, and metals, and misc. applies, incl. automotive interiors, belts, color cones., hats, hose construction, rainwear, shoes, television tubes, wire coating, etc. 

Bulk Micromachining, Fig. 6 SEM images of the fabrication results of the proposed method, (a) Etched glass surface with PR etch mask, (b) After removing the PR mask, (c) Close-up view of a sharp comer, (d) Cross-sectional view of the sealed microfluidic channel after fusion bonding... 

Thermal fusion bonding is a process that fuses more than one material or substrate via a thermal cycle. The temperature for performing this process is usually a bit higher than the glass transition temperature (Tg) of the material. 

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