The Confovis WAFERinspect AOI system for automated optical inspection (AOI) was created to help identify defects on any kind of surfaces where 3D structures in the range of 10nm to 10µm are critical to the function. When measuring wafer surfaces (e.g. of MEMS (MEMS inspection), 5G, microfluidics or advanced packaging wafers (Wafer Inspection) that have both diffuse and specular reflectivities, triangulation sensors come to their limits.
The Confovis AOI and metrology system WAFERinspect AOI uses color LED brightfield/darkfield illumination or triangulation sensors only to identify defects in a first step. In a second step the patented high-speed areal confocal sensor is used to measure such surfaces in question with an accuracy of up to 3nm and repeatability up to 2nm.
The Confovis automated optical inspection system is ideal for structures comprising a body (such as epoxy and silicon), metal bumps or solder pads, each of which may have complicated geometric shapes with different orientations.
Confovis AOI metrology: new horizons for complex applications
The Confovis AOI defect inspection and review systems are used for patterned and unpatterned wafers to find, identify and classify particles and pattern defects. Also defect detection and 3D particle measurement on reticles and pellicles to distinguish where the defects are located is a strength of the system. Fully integrated and customizable defect detection software from Neurocheck using AI is the core of the Confovis AOI defect detection system. For wired and wireless sensors, wafers and reticles the automated optical inspection provides comprehensive information for a wide range of wafer processes and reticle inspection. Covering all wafer surfaces and providing parallel data collection at high throughput for efficient process control, the system comprises optical review and classification techniques.
Defect Detection with AOI Systems in safety relevant applications
The system combines 2D and 3D inspections on one wafer. With this approach, a single system can be deployed for different inspection tasks, covering practically 200mm and 300mm wafers and all typical defect types on 2D and 3D structures (defect inspection). The Confovis approach uses results from high sensitivity bright field, dark field, or triangulation measurements to trigger 3D confocal areal measurements within the cluster. The accuracy of the confocal system comes close to AFM results enabling the user to resolve and monitor critical yield excursions, resulting in faster yield ramp and higher production yield.
AOI measurement tasks
Confocal 3D measurements
- Independent of materials: silicon, epoxy, glass, chrome, resist, etc.
- Measurements of demanding surfaces without artifacts (no ‘bat wings’)
- High speed: 60 confocal frames per second (250 mil. measuring points/s)
- Film Thickness / Layer Stack
- Step Height
- Oblong holes
- Macro defects
- Micro defects
- Particle Inspection
- Golden Sample
- Artificial Intelligence
- Neuronal networks
- Operator mode (visual inspection)
- Color images
- Extended depth of focus images
- Documentation by commentary function
- Digital inking
- Visual inspection with fine alignment, KLARFF-files
An metrology and AOI system with many benefits
- Measurements of different surface coats/materials, including reflecting and transparent layers; e.g. for assessment of undercuts
- Artifact free measurements of demanding surfaces (no “bat wings”)
- High degree of automation: manual, semi-automatic or fully automatic measuring system, as needed
- Wafer handling systems (EFEM) and wafer positioning systems available (flexible wafer sizes and types, frame handling, etc. possible)
- High-precision measuring technique: confocal with high vertical resolution of < 3 nm (VDI 2655)
AOI wafer inspection applications
Confovis WAFERinspect: AOI and Metrology System
Confovis provides a fully automated surface inspection system, designed to support volume production environment while delivering most accurate inspection and metrology capabilities. The flexible system supports the market’s most challenging applications, such as MEMS, LED, 5G and microfluidic structures through various process steps. Equipped with a wafer handling system as part of an Equipment Front End Modul (EFEM) various handling solutions for MEMS, Glass, Warped, Thin, Taiko wafers and more are available. The system can handle 4” to 12” wafer and supports the applicable SEMI standards. The communication with the host follows SECS/GEM