Paper
17 November 1986 Automated Defect Inspection For In-Process Semiconductor Devices
William H Arnold, Alan L Levine
Author Affiliations +
Proceedings Volume 0654, Automatic Optical Inspection; (1986) https://doi.org/10.1117/12.938282
Event: 1986 International Symposium/Innsbruck, 1986, Innsbruck, Austria
Abstract
The fabrication of very large scale integrated circuits, usually done on silicon substrates known as wafers, is a process by which successive layers of films are deposited and patterned. Photolithographic transfer of patterned images is performed fEom a master "reticle" with a step and repeat camera, with imaging Fspabilities of -2 x 108 discrete 1 elements in a single exposure of a field area of 2cm . Typical processes contain approximately 60 exposure fields per wafer level and have UP to 15 discrete levels. Each level requires its own reticle pattern. The number of devices printed on a single wafer varies but is usually between 50 and 1000 depending on the type of device and the wafer size. Even for successful processes, typically only 50-75% of available devices actually are functional at completion. Loss of these devices is primarily due to defects encountered in the processing. It is straightforward to create a first order estimate f the nominal defect density requi5ed to support such yields by using Poisson statistics. Assuming a device size of 0.5cm ' and 10 critical levels, the defect density required to give 60% die yield is given by 2: -nDoA Yield =e 1 where n = critical device levels (1) 1 + nAD A = area of device 0 Do = defect density per wafer Do = 0.13 defects/cm2 per critical level Since device killing defects can be smaller than 1.0um, the ability to discover such defects and remove the source causes of defects is critical.
© (1986) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
William H Arnold and Alan L Levine "Automated Defect Inspection For In-Process Semiconductor Devices", Proc. SPIE 0654, Automatic Optical Inspection, (17 November 1986); https://doi.org/10.1117/12.938282
Lens.org Logo
CITATIONS
Cited by 2 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Inspection

Semiconducting wafers

Optical inspection

Objectives

Cameras

Atmospheric particles

Reticles

RELATED CONTENT


Back to Top