Abstract: A novel method for bonding components has been disclosed. For bonding ceramic components the method involves placing at least three metal interlayers between the components. There is a central core metal layer and two other metal layers placed on either side of the core layer adjacent the ceramic components. The metal layers are heated to a temperature sufficient to transform at least part of the metal layers into a liquid. The temperature is maintained until the liquid begins to solidify and the first points of bonding between the components and the solidifying interlayer is established. This system can also be used to bond a ceramic component to a metal component. The metal component can be placed adjacent the central core metal layer without an intervening metal layer.

Abstract: Ceramics are joined to themselves or to metals using a transient liquid phase method employing three layers, one of which is a refractory metal, ceramic or alloy. The refractory layer is placed between two metal layers, each of which has a lower melting point than the refractory layer. The three layers are pressed between the two articles to be bonded to form an assembly. The assembly is heated to a bonding temperature at which the refractory layer remains solid, but the two metal layers melt to form a liquid. The refractory layer reacts with the surrounding liquid and a single solid bonding layer is eventually formed. The layers may be designed to react completely with each other and form refractory intermetallic bonding layers. Impurities incorporated into the refractory metal may react with the metal layers to form refractory compounds. Another method for joining ceramic articles employs a ceramic interlayer sandwiched between two metal layers.

Abstract: Ceramic and metal articles are joined using three metal layers one of which is a refractory metal or alloy. The refractory metal layer is placed between the other two layers, which each include a metal or alloy having a lower melting point than the refractory metal layer. The three metal layers are pressed between two articles to be bonded to form an assembly. The assembly is heated to a bonding temperature, at which the refractory metal layer remains solid, but the other two layers melt to form a liquid. The assembly is held at the bonding temperature. The refractory metal layer dissolves in surrounding liquid and a single solid bonding layer is eventually formed, at the bonding temperature, between the two articles. The bonding method may be referred to as a transient-liquid-phase or isothermal bonding method.

Abstract: A process for forming large-grain polycrystalline films from amorphous films for use as photovoltaic devices. The process operates on the amorphous film and uses the driving force inherent to the transition from the amorphous state to the crystalline state as the force which drives the grain growth process. The resultant polycrystalline film is characterized by a grain size that is greater than the thickness of the film.A thin amorphous film is deposited on a substrate. The formation of a plurality of crystalline embryos is induced in the amorphous film at predetermined spaced apart locations and nucleation is inhibited elsewhere in the film. The crystalline embryos are caused to grow in the amorphous film, without further nucleation occurring in the film, until the growth of the embryos is halted by imgingement on adjacently growing embryos. The process is applicable to both batch and continuous processing techniques.