Electron-beam testing of microwiring substrates

• Published in: Japanese Journal of Applied Physics Vol. 29; no. 11; pp. 2671 - 2674
• Main Authors: BRUNNER, M, SCHMID, R, SCHMITT, R, LISCHKE, B, WÖRNER, M, BERGH, N. K
• Format: Journal Article
• Language: English
• Published: Tokyo Japanese journal of applied physics 01-11-1990
• Subjects: Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron and ion emission by liquids and solids; impact phenomena; Electronics; Exact sciences and technology; Microelectronic fabrication (materials and surfaces technology); Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Characterization; Substrate; Multilayer; Test; Electron beam; Computer aided design; Electrical test
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/jjap.29.2671

The miniaturization of microwiring substrates which are used for high-density chip packaging imposes increasing problems on electrical testing. Mechanical probes fail to contact pads reliably in the 50 µm range and are limited to a fixed pad configuration. An electron-beam test system has been developed to overcome these problems. It uses CAD data for flexible beam positioning within a 10 cm × 10 cm field. An electron probe with a spot size of 40 µm is used for charging networks and reading pad voltages. The system has already demonstrated its operation by detecting shorts and opens on a limited number of substrates which were rejected as defective by a mechanical prober during the final test of the current production.