Glass-fabric carrier

Almost all film adhesives used in electronics assembly are either epoxies or poly-imides on a glass fabric carrier. Eihn adhesives may be thermoplastic or thermosetting... 

Henkel conductive epoxy glass-fabric carrier 150 °C ... 

E 104 glass fabric carrier coated with Larc TPI polyamic acid precursor... 

E-104 glass fabric carrier impregnated with Larc-TPI polyamic acid. The cure cycle is carried out under a pressure of 2.1 MPa by heating the assembly from the ambient to 343°C at a rate of 8°C min" followed by 1 h at that temperature. A postcure treatment at 343°C for 4-6 h is applied to the assemblies that are subsequently tested at temperatures higher than the Tg. 

The adhesive is manufactured in tape form by a hot-melt process. It is a tacky solid at room temperature. The integrity is maintained by using a finely woven glass fabric scrim as the carrier. This process is an excellent example of the compromises required in the technology of formulation. Some of the high-temperature performance that is expected from the phenolic resole is sacrificed for the improved bond strength and toughness afforded from the epoxy resin. The filler is added to make the thermal coefficient of expansion of the cured adhesive more metallic in nature. Dicyandiamide is the... 

Most carrier-active compounds ate based on aromatic chemicals with characteristic odor. An exception is the phthalate esters, which are often preferred when ambient odor is objectionable or residual odor on the fabric caimot be tolerated. The toxicity of carrier-active compounds and of their ultimate compositions varies with the chemical or chemicals involved. The environment surrounding the dyeing equipment where carriers are used should always be weU-ventilated, and operators should wear protective clothing (eg, mbber gloves, aprons, and safety glasses or face shields, and possibly an appropriate respirator). Specific handling information can be obtained from the suppHer or manufacturer. 

It is important to note that the entire NW-TFT device fabrication process is performed essentially at room temperature. Therefore, the assembly of high-performance NW-TFTs can be readily applied to low-cost glass and plastic substrates. It has been demonstrated, for example, that NW-TFTs can be fabricated on plastic substrates (Fig. 11.14d) with carrier mobilities comparable with those made on silicon substrates. Moreover, studies demonstrate that... 

The first representative of a potentiometric sensor was the pH-glass electrode invented in 1906 [35]. Decades of development resulted in the invention of many more ion-selective electrodes including more recently those based on neutral carrier membranes [36] and of the microelectronic fabricated ion selective field effect transistor (ISFET) [37]. 

A carrier or reinforcement is usually a thin fabric, cloth, or paper used to support the semicured adhesive composition to provide a tape or film. In tapes, the carrier is the backing on which the adhesive is applied. The backing may be used for functional or decorative purposes. In epoxy films or structural tape, the carrier is usually porous and the adhesive saturates the carrier. Glass, polyester, and nylon fabric are common carriers for supported B-staged epoxy adhesive films. In these cases, the carrier provides for a method of applying the adhesive and also may act as reinforcement and a internal shim to control the thickness of the adhesive. 

Glass, nylon, polyester, and cotton fabric or mat are often used as a carrier in tape or film adhesive systems. In addition to being a carrier and a reinforcement, the strands of the fabric offer an internal shim so that the bond line cannot be thinner than the thickness of these strands. Sufficient pressure need only be applied to cause the adhesive to flow so that the shims meet the substrate surfaces to provide a positive stop. Paper, mat, and other carrier materials may also be used for this purpose. 

Many film adhesives have a supporting carrier or reinforcement fabric incorporated into the adhesive to improve handling of the film and provide control of bond line thickness. The carriers are usually glass, polyester, or nylon fabrics of knitted, woven, or nonwoven construction. The difficulty with such carriers is that they can provide an effective way of moisture entering the bulk of the adhesive. Moisture can wick along the fiber-adhesive interface. Nylon carriers should especially be reviewed since they have a strong tendency to absorb moisture. 

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