Invention compositions are a replacement for high melting temperature solder pastes and preforms in high operating temperature and step-soldering applications. In the use of the invention, a mixture of metallic powders reacts below 350 degrees C. to form a dense metallic joint that does not remelt at the original process temperature.

A method of making a semiconductor including soldering a conductor to an aluminum metallization is disclosed. In one example, the method includes substituting an aluminum oxide layer on the aluminum metallization by a substitute metal oxide layer or a substitute metal alloy oxide layer. Then, substitute metal oxides in the substitute metal oxide layer or the substitute metal alloy oxide layer are at least partly reduced. The conductor is soldered to the aluminum metallization using a solder material.

Metal compositions and production processes are described. A process for the production of a metal composition includes a first distillation step separating off by evaporation primarily lead from a solder mixture of lead, tin, and antimony, thereby producing as a first concentrated lead stream. The process includes a second distillation step separating primarily lead and antimony from the metal composition, thereby producing a second concentrated lead stream and a second bottom product. The method also includes a third distillation step separating primarily lead and antimony from the second concentrated lead stream, thereby producing a third concentrated lead stream and a third bottom product.

Disclosed is a metal mixture composition containing lead and tin, and comprising by weight at least 10% tin and 45% lead, at least 90% of tin and lead together, more lead than tin, from 1-5000 ppm of copper, at least 0.42% antimony and at least 0.0001 % wt of sulphur, at most 0.1% of the total of chromium, manganese, vanadium, titanium and tungsten, and at most 0.1% of each one of aluminium, nickel, iron and zinc. Disclosed is also a process comprising a pre-treatment step for producing this metal mixture composition, followed by a vacuum distillation step wherein lead is removed by evaporation and a bottom stream is obtained comprising at least 0.6% wt of lead.

A process for a producing crude solder product and a copper product includes the steps of providing a black copper comprising >=50% wt of copper together with >=1.0% wt of tin and/or >=1.0% wt of lead, and refining a first portion of the black copper to obtain a refined copper product together with at least one copper refining slag. The process further includes the steps of recovering a first crude solder product from the copper refining slag, thereby forming a solder refining slag in equilibrium with the first crude solder product, and contacting a different portion of the black copper with the solder refining slag thereby forming a spent slag and a lead-tin based metal, followed by separating the spent slag from the lead-tin based metal.

A method of making a semiconductor including soldering a conductor to an aluminum metallization is disclosed. In one example, the method includes substituting an aluminum oxide layer on the aluminum metallization by a substitute metal oxide layer or a substitute metal alloy oxide layer. Then, substitute metal oxides in the substitute metal oxide layer or the substitute metal alloy oxide layer are at least partly reduced. The conductor is soldered to the aluminum metallization using a solder material.

The present disclosure relates to tubular welding electrodes that have a metallic sheath surrounding a granular core, wherein the metallic sheath comprises a metal matrix composite (MMC) that includes a ceramic material and aluminum or an aluminum alloy. The ceramic material may be in the form of microparticles or nanoparticles. The present disclosure also relates to method for making such tubular welding electrodes.

A method of making a semiconductor including soldering a conductor to an aluminum metallization is disclosed. In one example, the method includes substituting an aluminum oxide layer on the aluminum metallization by a substitute metal oxide layer or a substitute metal alloy oxide layer. Then, substitute metal oxides in the substitute metal oxide layer or the substitute metal alloy oxide layer are at least partly reduced. The conductor is soldered to the aluminum metallization using a solder material.

A method of making a semiconductor including soldering a conductor to an aluminum metallization is disclosed. In one example, the method includes substituting an aluminum oxide layer on the aluminum metallization by a substitute metal oxide layer or a substitute metal alloy oxide layer. Then, substitute metal oxides in the substitute metal oxide layer or the substitute metal alloy oxide layer are at least partly reduced. The conductor is soldered to the aluminum metallization using a solder material.

A disclosed process produces at least one concentrated copper product together with at least one crude solder product, starting from a black copper composition with at least 50% of copper together with at least 1.0% wt of tin and at least 1.0% wt of lead The process includes the step of partially oxidizing the black copper thereby forming a first copper refining slag, followed by partially reducing the first copper refining slag to form a first lead-tin based metal composition and a first spent slag. The total feed to the reducing step includes an amount of copper that is at least 1.5 times as high as the sum of the amounts of Sn plus Pb present, and the first spent slag includes at most 20% wt total of copper, tin and lead together.