A Tutorial on STDF Fail Datalog Standard

Advances in technology are making it imperative to collect detailed structural IC fail data during manufacturing test to improve yield. However, there is currently no standard format for communicating and storing such structural fail data efficiently. This leads to ad-hoc tool-specific solutions, which do not offer interoperability required in a typical multi-tool, multi-vendor customer environment. These ad-hoc solutions result in unnecessary investment in development of point-to-point interface solutions that are ultimately still not integrated with the traditional data collection for a unified yield analysis data format. Expanding an established datalogging standard to accommodate the new requirements solves these issues. Standard Test Data Format (STDF) is the predominant format used today for traditional failure datalogging storage, but in its current form falls far short in handling the new high-volume structural failures for yield learning. A group of more than 20 companies from ATE, EDA, Semiconductor and Yield Management companies has been working on a new enhanced STDF standard that addresses the new requirements. This paper provides the overview of the new enhanced standard.