By John O’Donnell, April 8th 2018

I recall doing Characterisation on many occasions on analog and mixed signal devices twenty years or so years ago. The goal of Characterisation then and now is to make sure that the variation in behaviour of semiconductors due to changes in Material or Test Conditions is fully understood. Examples of Material Conditions are Process Corners which represent the extremes of fabrication parameters at which the devices are still expected to function. Examples of Test Conditions include Voltage, Temperature and Operating Frequency.

Twenty years ago Characterisation used to take two or three weeks and it was and is a major item in the critical path. Designers are waiting eagerly for what you find. With tools up to now it’s from a few days to a week to complete characterisation once testing is finished. Twenty years ago a fast database was out of the question and Excel was your friend. Unfortunately for many companies it still is their friend and means they spend too much time still generating the reports.

With modern tools the characterisation report should take only a few hours once testing is complete.


Figure: Normal Probability Plot from yieldHUB with some groups highlighted

The following are Huge Time Savers in any such Characterisation tool:

  • Simple for the test engineer to generate compatible datalogs (e.g. STDF or text based) so that the software automatically detects both the Material and Test Conditions associated with each test result
  • Fast, Interactive Analysis across all conditions with Flexible Filtering and Regrouping
  • Multiple chart types for maximum visualisation
  • Automated report generation across hundreds and hundreds of tests with varied visualisations throughout the report
  • Reports may be saved on-line and be combined into a Master Report
  • Ability to add comments on-line to the report & to each test individually
  • Ability to easily replace a subset of the data if retesting is required for a certain set of conditions
  • Easy navigation throughout the report
  • Easy sharing of the report with colleagues

Using the above principles in the design of such a characterisation tool, many days of work in report preparation and rework can be reduced to only hours. This greatly accelerates discussions around the key issues with designers and foundry engineers. In the semiconductor industry, where time to market is so important in new product introduction, this makes a tangible difference.

Contact:  +353 61 309745 or any of our sales agents worldwide if you are interested in finding out more. We can set up a web conference call with you to demo these capabilities.