Patents Assigned to PDF Solutions
  • Patent number: 7932105
    Abstract: Systems and methods for detecting and monitoring Nickel-silicide process and induced failures. In a first method embodiment, a method of characterizing a Nickel-silicide semiconductor manufacturing process includes accessing a test chip including a parallel coupled chain of transistors, wherein the transistors are designed for inducing stress into Nickel-silicide features of the transistors, and for increasing a probability of a manufacturing failure of the Nickel-silicide features. A biasing voltage is applied to one terminal of the parallel coupled chain, all other terminals of the parallel coupled chain and grounded, and current is measured at each of the all other terminals of the parallel coupled chain. This process is repeated for each terminal of the parallel coupled chain. The measured currents from all possible conduction paths are compared to determine a manufacturing defect in the parallel coupled chain of transistors.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: April 26, 2011
    Assignee: PDF Solutions
    Inventors: Sharad Saxena, Jae-Yong Park, Benjamin Shieh, Mark Spinelli, Shiying Xiong, Hossein Karbasi
  • Patent number: 7568180
    Abstract: A method comprises the steps of: (a) simulating on a processor a fabrication of a plurality of layout patterns by a lithographic process; (b) determining sensitivities of the layout patterns to a plurality of parameters based on the simulation; (c) using the sensitivities to calculate deviations of the patterns across a range of each respective one of the parameters; and (d) selecting ones of the patterns having maximum or near-maximum deviations to be used as test patterns.
    Type: Grant
    Filed: February 22, 2005
    Date of Patent: July 28, 2009
    Assignee: PDF Solutions
    Inventors: Hans Eisenmann, Kai Peter, Dennis Ciplickas, Jonathan O. Burrows, Yunqiang Zhang Zhang
  • Publication number: 20090033353
    Abstract: Systems and methods for electrical characterization of inter-layer alignment. In one embodiment, a wafer including a plurality of test structures are accessed. The plurality of test structures include chains of conductive segments on multiple layers, coupled by vias. The plurality of test structures are designed with varying amounts of intentional misalignment between the multiple layers. The reactance of each of the plurality of test structures is measured. The reactance is analyzed to determine the process-induced inter-layer misalignment of the integrated circuit wafer.
    Type: Application
    Filed: July 31, 2008
    Publication date: February 5, 2009
    Applicant: PDF SOLUTIONS
    Inventors: Kaung Shia Yu, Franz Xaver Zach