SMT007 Magazine


Issue link:

Contents of this Issue


Page 33 of 80

34 SMT Magazine • November 2014 Accuracy and repeatability of the procedures are increasing along with the higher degree of automation in the machine which can operate standard SMT components and bottom termi- nated components from 1 x 1 mm to 50 x 50 mm without any special tools for desoldering, solder- ing or placement. No component data needs to be supplied or evaluated; the operator can ex- ecute the rework process starting with the first assembly and the first component. The success rate can easily rise by more than 10% compared to simple, non-automated repair procedures. Automated processes can save up to 30–50 % of the operator's time. The alignment of com- ponents is done by the rework system and the operator can concentrate on other activities with operator generated alignment mistakes re- moved reducing defects during rework. smt references 1. MVTEC: HALCON Functionality; Cam- era calibration, Presentation, Mvtec Software GmbH, 2002. 2. "A computational approach to edge de- tection." IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 8, 1986, p. 690. 3. Workshop "Automatic Learning Systems in Image Processing," Math&Tech Engineering GmbH, 25.02.2013, p. 4. Joerg Nolte is vice president for r&D rework, inspection and tools at erSa Gmbh. When moving through a conductive material in an electric field, electrons tend to follow the path of least resistance--which runs in the direc- tion of that field. But now physicists at MiT and the university of Manchester have found that when a sheet of graphene is placed atop another two-dimen- sional material, electrons instead move sideways, perpendicular to the electric field. What's more, two separate streams of elec- trons would flow in opposite directions, both crosswise to the field, canceling out each other's electrical charge to produce a "neutral, charge- less current," explains leonid levitov, an MiT professor of physics and a senior author of a paper describing these find- ings this week in the journal Science. levitov and co-author an- dre geim at Manchester say this flow could be altered by applying a minute voltage on the gate, allowing the material to function as a transistor. "it is widely believed that new, unconvention- al approaches to information processing are key for the future of hardware," levitov says. "This belief has been the driving force behind a num- ber of important recent developments, in partic- ular spintronics"--in which the spin of electrons, not their electric charge, carries information. in their experiments, levitov, geim, and their colleagues overlaid the graphene on a layer of boron nitride--a two-dimensional material that forms a hexagonal lattice structure, as graphene does. Together, the two materials form a super- lattice that behaves as a semiconductor. Whether or not this effect can be harnessed to reduce the energy used by computer chips remains an open question, lev- itov concedes. The work has great po- tential, guinea adds, because "two-dimensional materials with special topological prop- erties are the basis of new tech- nologies for the manipulation of quantum information." Physicists Find new Way to Push electrons Around new PLacement tecHnoLogy For rework systems continues feaTure

Articles in this issue

Archives of this issue

view archives of SMT007 Magazine - SMT-Nov2014