Partner und Internationale Organisationen
(Englisch)
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A, B, BG, CZ, DK, FIN, F, D, GR, H, IRL, I, LT, N, PL, P, RO, SK, SI, E, S, CH, TR, GB
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Abstract
(Englisch)
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A technique was developed that allows mask- and resistless electrodeposition of material patterns of arbitrary shape on semiconductor surfaces with sub-micrometer resolution. The principle is that damaged p-Si shows an 'affinity' for electrochemical reactions due to a facilitated breakdown of the blocking Schottky barrier at the semiconductor/electrolyte interface. This can be used to selectively perform electrochemical reactions at the defect sites; high resolution defects were obtained by ion bombardment. Ni, Cu, Au, and Pd structures have been deposited with a resolution of down to 150nm. Key parameters for both the implantation process and electrochemical deposition were identified and the process was improved accordingly. It has been shown that low ion implant doses (¾ ~5·10^12 ions/cm^2) do not create enough damage for complete coverage of the implant while high ion doses (' ~10^15 ions/cm^2) lead to amorphization of the substrate, effectively inhibiting the deposition process. Also, the addition of BTA to a Cu containing electrolyte lead to smoother and finer deposits, a prerequisite for obtaining sub-micrometer resolution. Finally, in an informal collaboration with the Fraunhofer Gesellschaft, we were able to show that the process throughput can be vastly increased by using a broadband ion-implanter in conjunction with a stencil mask (ion projection direct structuring, IPDS) instead of a FIB for defect creation. Resolution was good and patterns with a resolution of down to 150nm were obtained over a surface of several mm2. The combination of IPDS and selective electrochemistry is of interest with respect to possible industrial applications of this technique.
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