Inkjet-printed electrical interconnects for high resolution integrated circuit diagnostics

• Published in: Communications engineering Vol. 2; no. 1; p. 21
• Main Author: Jacobs, Kristof J. P.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 02-05-2023; Springer Nature B.V
• Subjects: 639/166/987; 639/624/1107/328; 639/925/930; Defects; Electrical properties; Engineering; Failure analysis; High resolution; Inkjet printing; Integrated circuits; Laboratories; Microscopes; Semiconductor devices; Semiconductors; Silicon; Spatial resolution; Structural analysis; Transistors
• ISSN: 2731-3395; 2731-3395
• DOI: 10.1038/s44172-023-00073-4

As semiconductors continue to shrink in size and become more three-dimensional in shape, the size of defects that can induce a failure also reduces, pushing the need for better fault isolation. The resolving capability of microscopes used in failure analysis (FA) is frequently limited by how close the microscope can be brought to the circuit under test. Accessibility is often restricted by the presence of probe needles or wire bonds that are needed to power up the device during the measurement. Here, I describe a robust, rapid and cost-effective method to overcome the contacting bottleneck by re-routing the probe pads with a low-profile redistribution layer, realized by conductive inkjet printing. I demonstrate that the method enables analytical FA with high spatial resolution on a backside power delivery network structure in combination with the optical beam induced resistance change (OBIRCH) technique. Electrical and structural characterization of the printing process are also reported.
Kristof Jacobs reports a method for microscopic defect analysis of semiconductor devices during electrical stimulation, without interference by probe needles usually located in close proximity to the objective lens. His approach re-routes the probes that need to be electrically contacted during the measurement with a low-profile redistribution layer realized by conductive inkjet printing.