LONDON Oxford NanoScience Ltd. has said that its 3DAP three-dimensional atom probe can now be used on silicon structures, so that semiconductor device manufacturers can determine both the elemental identity and position of individual atoms.
The 3DAP has been successfully applied to semiconductor samples by the use of laser light to liberate atoms from the sample. Such probing will be critical for the design, engineering and manufacturing of next-generation devices and in particular device yields, performance and reliability, Oxford NanoScience (Milton Keynes, England) said.
The 3DAP works by evaporating individual atoms from a semiconductor sample, measuring their atomic mass and then calculating their position in the sample's three-dimensional structure. A detailed three-dimensional atomic model of the sample can then be visualized using software to perform a reconstruction.
Previously the company's 3DAP machines have used high voltage pulses to evaporate atoms from conductive samples a system suitable for analysis of electrically inactive devices, but not suitable for use with semiconductor materials. Oxford NanoScience is now using a laser excitation mechanism to open up the technique to semiconductor samples.
The laser-excited 3DAP has been applied to a variety of metal multilayer structures, including metal oxide layers, grown on a silicon substrate, the company said.
The new instrument uses the company's established 3DAP analysis system, originally developed at the University of Oxford, combined with femtosecond laser excitation. Accurate chemical compositions can be obtained for all or selected regions of the data with element detections limits in the range of 1 to 100 parts per million. Sample analyses of millions of atoms can be run in just 10 minutes and small quantities of atoms with similar atomic mass can be separated out by the instrument.
Results obtained from the laser-excited 3DAP system by Oxford NanoScienceare set to be available at the Semicon West exhibition, which takes place July 12 to 14, at the Moscone Center, San Francisco, California.