AIMS fab 193

Aerial Imaging for Mask Shop

Carl Zeiss AIMS fab 193, is a system to optically emulate steppers/scanners. The system quickly and accurately predicts with the help of new and innovative features the printability of all types of mask defects for every kind of reticle enhancement technique. The specially designed minimized partial contamination.
The system can be used in the mask shop to speed up the development and production of a new generation of masks.

Innovative Features
•  Scanner/Stepper emulator for the 193 nm wavelength
•  Specially designed 193 nm imaging and illumination optics
•  Light source: ArF-excimer-laser
•  High resolution node
•  Utilizing 193nm illumination
•  Windows NT based software
•  Optionally: mask handling


Applications

•  BIM, PSM and OPC masks performance evaluation (comparison, to design simulation)
•  Completing the mask repair cycle
•  Mask control and stepper/scanner optimization in wafer production
•  Imaging process optimization through direct access to the system's, imaging and illumination pupils.

Technical Data

Optics
Wavelength: 193 nm
Numerical aperture (NA) range: 0.60 - 0.92 in 0.01 steps
Sigma aperture range: 0.3 - 1.00 in 0.01steps

Illumination
Light source: ArF excimer laser
System Laser: Class 1
Off-axis patterns: Annular (1:3, 2:3, 1:2), quadruple, quasar, dipole and customer specific design

Cameras
Overview video CCD camera: 1/3" CCD 752 x 582 pixel DC 12 V/1.4 W
UV sensitive cooled CCD array: 1317 x 1035 pixel, pixel size 6.8 x 6.8 μm

Monitor
18" High Resolution Flat Screen

Scanning stage
Travel range in x/y: 240 x 230 mm
Resolution (maximum): 100 nm
Mask holder: 5", 6" and 7"

Masks
Sizes: 5" (90 mil), 6" (120 mil, 250 mil), 7" (250 mil) and 9" (350 mil)
Types: BIM, PSM, OPC and combinations there of, with or w/o pellicle

Masks
Sizes: 5" (90 mil), 6" (120 mil, 250 mil), 7" (250 mil) and 9" (350 mil)
Types: BIM, PSM, OPC and combinations there of, with or w/o pellicle

Power
Voltage: 190 V - 230V
Frequency: 50/ 60 Hz
Power rating: 2000 W on average,

Dimension
Width x depth x height: 800 mm x 790 mm x 770 mm
Weight: main system (base system): 700 kg , electronic rack: 110 kg

AIMS Software
Software operating under Windows NT.
Office version available.
System Control and Image Acquisition:
Selection of wavelength, illumination type, aperture control (NA and sigma), automated alignment capability, mask positioning including review capability, focus control, video autofocus, camera control, image capture, image normalization through clear field capture, single image mode and through-focus mode.

Data Analysis:
Intensity profiles, contour plots, linewidth versus threshold plots, linewidth versus defocus plots, exposure versus defocus plots, 3D intensity plot, histogram, 2 image comparison.

Aerial Imaging

It shows how it prints!
Aerial imaging is an optical technique which measures the
aerial image directly from any type of mask.

Aerial Image of lines and spaces pattern. The center line shows a defect.

By using equivalent optical conditions for wavelength, numerical aperture and illumination type like steppers / scanners, it provides rapid feedback on lithographic performance. The image of a feature is equivalent to the one printed with incident light on the resist of the wafer. Applying through- focus measurements allows you to extract the process latitude and de-focus exposure matrix.


General Applications

•Performance evaluation and qualification of all types of litho masks (BIN, PSM, OPC)
•Printability/ non-printability check of defects and defect analysis
•Repair verification
•Prediction of expected resist linewidth after litho process
•Evaluation of phase errors based on CD predictions
•Incoming quality control
•Transmission analysis
•Wafer process optimization through direct variation of NA- and sigma-values