Abstract: Conductive patterns and methods of using and printing such conductive patterns are disclosed. In certain examples, the conductive patterns may be produced by disposing a conductive material between supports on a substrate. The supports may be removed to provide conductive patterns having a desired length and/or geometry.

Abstract: Methods for die attachment of multichip and single components including flip chips may involve printing a sintering paste on a substrate or on the back side of a die. Printing may involve stencil printing, screen printing, or a dispensing process. Paste may be printed on the back side of an entire wafer prior to dicing, or on the back side of an individual die. Sintering films may also be fabricated and transferred to a wafer, die or substrate. A post-sintering step may increase throughput.

Abstract: A lead-free solder alloy comprising 35-59 wt % Bi, Mn in a concentration up to 1.0 wt %, Cu in a concentration of up to 1 wt %, and balance Sn, together with any unavoidable impurities. Some embodiments also contain up to about 1 wt % Ag.

Abstract: A method of forming a solder joint, the method comprising: (i) providing a solder flux; (ii) providing solder particles; (iii) providing two or more work pieces to be joined; and (iv) heating the solder flux and the solder particles in the vicinity of the two or more work pieces to be joined to form: (i) a solder joint between the two or more work pieces to be joined, and (ii) a solder flux residue. The solder flux residue substantially covers the exposed surfaces of the solder joint.

Abstract: A sintering powder, wherein a least a portion of the particles making up the sintering powder comprise: a core comprising a first material; and a shell at least partially coating the core, the shell comprising a second material having a lower oxidation potential than the first material.

Abstract: Flux formulations that remain pliable and tack-free after deposition are disclosed. In certain examples, the flux comprises a first component and an effective amount of a second component to provide a pliable flux after deposition. The flux may also include activators, plasticizers, surface active agents and other components.

Abstract: Conductive patterns and methods of using and printing such conductive patterns are disclosed. In certain examples, the conductive patterns may be produced by disposing a conductive material between supports on a substrate. The supports may be removed to provide conductive patterns having a desired length and/or geometry.

Abstract: Flux formulations that remain pliable and tack-free after deposition are disclosed. In certain examples, the flux comprises a first component and an effective amount of a second component to provide a pliable flux after deposition. The flux may also include activators, plasticizers, surface active agents and other components.

Abstract: A method for recovering tin and/or tin alloy from a substrate comprising providing a substrate having tin and/or tin alloy thereon; contacting the tin and/or tin alloy with a stripping solution comprising an inorganic acid and a persulfate compound; recovering tin salt and/or tin alloy salt precipitated from the stripping solution; and recovering tin and/or tin alloy from the tin salt and/or tin alloy salt, respectively.

Abstract: Methods for die attachment of multichip and single components may involve printing a sintering paste on a substrate or on the back side of a die. Printing may involve stencil printing, screen printing, or a dispensing process. Paste may be printed on the back side of an entire wafer prior to dicing, or on the back side of an individual die. Sintering films may also be fabricated and transferred to a wafer, die or substrate. A post-sintering step may increase throughput.

Abstract: A lead-free solder alloy, comprising from 35 to 59% wt Bi; Cu in a concentration up to 1.0 wt %; from 0.01 to 0.5 wt % Ni; and the balance Sn, together with any unavoidable impurities, with certain embodiments further comprising Ag, such as up to 1 wt % Ag.

Abstract: Materials for die attachment such as silver sintering films may include reinforcing, modifying particles for enhanced performance. Methods for die attachment may involve the of such materials.

Abstract: A flux comprising one or more amines which is especially useful as a solder flux in soldering operations involving reactive metals such as aluminum; and a process for making aluminium surfaces solderable using the flux and conventional solders.

Abstract: Dual-side reinforcement (DSR) materials and methods for semiconductor fabrication. The DSR materials exhibit the properties of conventional underfill materials with enhanced stability at room temperature.

Abstract: Certain embodiments are directed to methods, devices and systems designed to remove selected portions of a material to expose an underlying material or substrate. One or more electrical components may be coupled to the underlying substrate through an electrical contact. Kits and systems for producing electrical contacts are also provided.

Abstract: A lead-free solder alloy comprising 35-59 wt % Bi, Mn in a concentration up to 1.0 wt %, Cu in a concentration of up to 1 wt %, and balance Sn, together with any unavoidable impurities. Some embodiments also contain up to about 1 wt % Ag.

Abstract: An alloy suitable for use in a wave solder process, hot air levelling process, a ball grid array or chip scale package comprising no more than 3 wt.% bismuth, from 0.15-1.5 wt.% copper, from 0.1-1.5 wt.% silver, and the balance tin, with optionally other alloying elements in certain embodiments, together with unavoidable impurities.

Abstract: A lead-free, antimony-free tin solder which is reliable at high temperatures and comprises from 3.5 to 4.5 wt. % of silver, 2.5 to 4 wt. % of bismuth, 0.3 to 0.8 wt. % of copper, 0.03 to 1 wt. % nickel, 0.005 to 1 wt. % germanium, and a balance of tin, together with any unavoidable impurities.

Abstract: An alloy suitable for use in a wave solder process, reflow soldering process, hot air levelling process or a ball grid array, the alloy comprising from 0.08-3 wt. % bismuth, from 0.15-1.5 wt. % copper, from 0.1-1.5 wt. % silver, from 0-0.1 wt. % phosphorus, from 0-0.1 wt. % germanium, from 0-0.1 wt. % gallium, from 0-0.3 wt. % one or more rare earth elements, from 0-0.3 wt. % indium, from 0-0.3 wt. % magnesium, from 0-0.3 wt. % calcium, from 0-0.3 wt. % silicon, from 0-0.3 wt. % aluminum, from 0-0.3 wt. % zinc, and at least one of the following elements from 0.02-0.3 wt % nickel, from 0.008-0.2 wt % manganese, from 0.01-0.3 wt % cobalt, from 0.01-0.3 wt % chromium, from 0.02-0.3 wt % iron, and from 0.008-0.1 wt % zirconium, and the balance tin, together with unavoidable impurities.

Abstract: Particles and particle films are provided. In certain examples, particles produced from a single phase process may be used to provide industrial scale synthesis of particles for use in devices such as printed wiring boards.