Product Specifications : kSA MOS UltraScan
Version: 2.0
- kSA MOS UltraScan
- kSA MOS UltraScan Measurement Technologies
- kSA MOS UltraScan Models
- kSA MOS UltraScan Functional Specifications
- kSA MOS UltraScan System Specifications
- kSA MOS UltraScan Integrated Software
- Distributors
kSA MOS UltraScan
Flexible,
High-Resolution
Curvature, Stress,
Thickness, and
Reflectance Mapping,
All in One Tool!
kSA MOS UltraScan is a flexible, high-resolution scanning curvature, stress, thickness, tilt, and absolute
reflectance measurement system. Based on the proven technology of our standard in-situ kSA MOS system,
the kSA MOS UltraScan uses a two-dimensional laser array to simultaneously measure the sample curvature in
two orthogonal directions and performs XY scanning to generate complete measurement mapping of
semiconductor wafers, optical mirrors, lenses, or practically any polished surface.
kSA MOS UltraScan provides high resolution XY scanning with uniform spatial scan resolution over the entire
wafer/sample surface as small as 1µm. Scans are fully programmable for line scans, selected area maps, and
full area maps, perfect for circular, square or patterned samples. The system also provides quantitative film
stress analysis by first scanning the sample and then re-scanning the sample post-process.
Measures: |
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Curvature |
Bow height |
Thin film stress |
Tilt |
Absolute reflectance |
Film thickness and spectral reflectance (Optional) |
Materials: |
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Wafers |
Optical Mirrors |
Lenses |
Glass |
Polished/Smooth Surfaces |
kSA MOS UltraScan Measurement Technologies
kSA MOS: The kSA Multi-beam Optical Sensor, or kSA MOS,
technology is based on a patented approach which uses a single laser
to generate a two dimensional laser array. This laser spot array is then
reflected off the sample surface and into a high resolution camera
imager. Changes in the reflected laser array spot spacing at each point
on the sample are used to determine the localized sample curvature in
both the X and Y direction. In this way, the system directly measures
the curvature and stress in two dimensions simultaneously, something
that single or dual beam curvature and stress tools simply cannot
capture.
Simultaneous detection of the laser array also makes the
measurement inherently less sensitive to sample vibration compared
with systems that rely on scanning the laser spot on the surface of the sample to measure the local curvature, leading to kSA MOS’s increased curvature resolution capability. Since all the laser spots move together at the same frequency, movement or tilt is not incorrectly detected as a change in sample curvature.
XY Scanning: kSA MOS UltraScan is equipped XY scanning over a 300mm x 300mm area. This provides the advantage of uniform spatial data resolution over the entire sample, rather than losing spatial resolution at large diameters, which is typical in linear scanning systems equipped with rotation stages. Moreover, it provides easy measurement set up for rectangular samples or for mapping limited areas of a sample.
Curvature: kSA MOS UltraScan is equipped with both flat and curved reference mirrors for quick and easy curvature calibration. As such, the absolute curvature of your sample is measured directly from the absolute laser spot spacing, resulting in high accuracy single point and scanning curvature measurements. Through the use of sophisticated image processing and data analysis algorithms, the kSA MOS UltraScan can easily detect sub-micron changes in spot position due to changes in sample curvature, which translates to the highest curvature/stress resolution metrology tool available.
Absolute Reflectance: Absolute reflectance of the sample at the laser wavelength is determined by measuring
the integrated intensity of the laser spots on the detector and can be calibrated with a mirror or sample
reference. This provides useful information with respect to the quality or film uniformity of the measured
sample.
Bow Height: When a laser is reflected off a bowed sample, the reflected angle will differ at different points on
the sample. The automated laser tracking in the kSA MOS UltraScan optics not only keeps the laser array
centered on the detector but also measures the changes in the angle of reflection of the laser array in order to
determine the local sample bow height.
Film Stress: To generate a thin film stress map of a sample, the local curvature of the sample must be
determined both pre- and post-deposition. Based on the change in the local curvature from the pre- and postprocess curvature maps, as well as the substrate thickness, the biaxial modulus of the substrate and the film
thickness, the thin film stress is determined. The changes in stress of a thin film after processing may also be
determined from the curvature maps measured after the subsequent processing steps.
Spectral Reflectance and Film Thickness (optional add-on): Equipping the kSA MOS UltraScan optics with a light source and a fiber-coupled spectrometer, the spectral reflectance of the sample can be measured at each point on the sample. Using proprietary kSA metrology software, the reflectance can be used to determine the thickness of a multi-layer film stack, given the film materials’ dispersion curves. The thickness can be mapped along with other measured parameters such as wafer curvature and film stress. The spectral reflectance date can also be exported to other applications for device modeling, etc.
kSA MOS UltraScan Models
Standard Package | |
---|---|
Model | Description |
kSA MOS UltraScan MOS-US |
|
Options | |
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Options | Description |
NIR Spectral Reflectance and Film Thickness Module M-SR-1670/U |
|
Large Format Camera M-HRD/U |
|
405 nm Laser and Optics M-405/U |
|
4” Optics M-4inch/U |
|
Custom Sample Holders |
|
Custom Large Area Panel Scanning |
|
Large Diameter Mirror Curvature Mapping (up to 1.5m diameter) |
|
Thermal Process Chamber |
|
kSA MOS UltraScan Functional Specifications
Standard MOS-US Specifications | |
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Sample Requirements | A smooth surface with >1% reflectivity at laser wavelength1 |
Standard Sample Holder | Holds 50, 75, 100, 150, 200, 300mm diameter samples; custom samples sizes upon request |
Scan Range | Up to 300mm in diameter, user programmable X and Y measurement range |
XY Stage Resolution | 1µm, user programmable measurement step size |
Average Curvature Resolution | 4x10-5m-1 (Defined as the standard deviation of 100 consecutive measurements at the center of the included reference mirror.) |
Average Curvature Repeatability | 2x10-5m-1 (Defined as standard deviation of the average curvature of 10 line scans with a minimum of 16 measurement points per line scan.) |
Radius of Curvature Range at Center2 | Minimum Concave: 2.0m Minimum Convex: -2.0m Maximum Concave: 50km Maximum Convex: - 50km |
Stress Accuracy3 | 1% or 0.32MPa whichever is greater |
Stress Resolution3 | 0.32MPa (Based on measured curvature resolution.) |
Average Stress Repeatability3 | 0.32MPa (Defined as standard deviation of the average stress from 10 scans.) |
Stress Range at Sample Center2,3 | Minimum Concave: 7800MPa Minimum Convex: 7800MPa Maximum Concave: 0.32MPa Maximum Convex: 0.32MPa |
Maximum Bow Height2,3 | 0.67mm at the edge of 300mm diameter wafer |
Bow Height Resolution | 2x10-2µm (Defined as standard deviation of the average bow height from 10 scans.) |
Bow Height Repeatability | <0.2µm |
Reflectivity Accuracy | > 0.1% of calibrated value (from reference mirror) |
Thickness4 | Single layer and film stack thickness determination of semi-transparent materials up to ~20µm in thickness. |
All measurements require a suitable measurement environment; large changes in ambient air temperature and air currents can impact tool performance.
1For samples with low reflectivity and/or roughness, k-Space suggests testing of a representative sample to ensure measurement compatibility.
2For radius of curvature, stress, and bow height ranges at a given diameter and/or application, please contact your k-Space representative.
3Assumes 725µm Si substrate thickness, 180GPa biaxial modulus for Si substrate, and 1µm film thickness. Specifications vary with substrate material, thickness, and film thickness.
4Available with M-SR-1670/U option. Thickness specification based on a single layer GaN film on sapphire substrate. Note layer and substrate must be different materials for thickness measurement.
kSA MOS UltraScan System Specifications
Sample Holder:
Wafer holder machined from solid aluminum block for mechanical stability. The standard stage holds 50, 75, 100, 150, 200, and 300mm diameter samples. Stage is equipped with both a flat reference and a 10m radius of curvature mirror for automated, easy, and reproducible system calibration. Custom sample holders quoted separately.
System Frame:
A robust welded steel frame houses the entire wafer holder, control electronics, and metrology system, so there is no need for an expensive vibration isolation table to house this stand alone unit. The frame has retractable castors so that the system can rest on vibration isolation pads if desired.
Controller:
The kSA MOS UltraScan system is supplied with a fully configured, Windows 10, multi-core CPU, A4 rack mounted computer system with a 22” LCD Monitor on a frame mounted swing arm. Please refer to the kSA Computer Product Specifications for the latest computer configuration. k-Space does not recommend or encourage customers to substitute or update their own computer for the controller. The kSA MOS UltraScan system uses several data acquisition boards that require specific bus slots and additional I/O slots on the back plane of the computer chassis.
Facility Requirements:
System Power: 110 or 220V, at 220V the system draws 3 – 4A.
System Dimensions: W=70cm, L=101.6cm, H= 156cm to 160cm, depending on the feet adjustments. Sample drawer extends an additional 45cm when opened. Monitor arm can attach to the left or right side, and it extends to the side.
System Weight: 295kg (650lbs).
Floor: The kSA MOS UltraScan is designed to meet factory specifications on a standard, solid (non-raised) floor. If the instrument is installed on a raised floor, it will not meet listed specifications for resolution and repeatability. If the room has a raised floor, the instrument should be installed on a platform with pillar supports to the sub-fab floor.
Air Ducts: The system is fully enclosed with a top cover that covers the optical head, gantry stage, and laser beam path to the sample. The sample is fully enclosed during measurement. Strong airflow directly on the tool can cause vibration that will impact resolution and repeatability. Therefore, locating the tool in the direct flow of an air duct should be avoided.
Photograph of kSA MOS UltraScan with MOS optics, scanning stage and sample holder exposed.
Detectors:
The MOS UltraScan system utilizes a camera for imaging the laser array. A larger format, high resolution
detector may be required for some applications.
Standard Detector | Large Format Detector (with M-HRD/U) | |
---|---|---|
Model | K1400-12 | k3300-14 |
camera Format | 2/3 type, Sony ICX285 Progressive scan | 4/3 type, KAI-08050 Progressive scan |
Resolution | 1360 x 1024 pixels (1.4MP) | 3296 x 2472 pixels (8MP) |
Pixel size | 6.45µm | 5.5µm |
Sensing area | 8.8mm x 6.6mm | 18.13mm x 13.6mm |
Bit depth | 12-bit | 14-bit |
Dynamic Range | 58dB | 62dB |
Exposure time | Variable from 10µs to 77.3s | Variable from 10µs to 26.8s |
Output format | GigE | GigE |
Power | 12V DC (internal from computer) or external 120/240V 210mA current consumption | 12V DC (internal from computer) or external 120/240V 210mA current consumption |
Lasers:
The kSA MOS UltraScan system utilizes fiber-coupled, Peltier-cooled laser diode packages with integrated current controller and temperature controller for generating the laser array. A different laser wavelength and associated optics may be required/desirable for some applications. Note: All high-power beams are confined within the kSA MOS UltraScan housing even when the cover is removed for alignment. The cover is not interlocked, but may be upon request. Direct access to the main beam is necessary during alignment.
660 nm (MOS-US Standard) | 405 nm (with M-405/U) | |
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Operation Mode | Constant current | Constant current |
Spot Size | ~ 0.8mm spot diameter, typical array is 6x4mm (4x3 spot array) | ~ 0.8mm spot diameter, typical array is 6x4mm (4x3 spot array) |
Power | > 70mW (<10µW exits the optical enclosure) | > 50mW (<10µW exits the optical enclosure) |
Stability | ≤ 0.2% | ≤ 0.2% |
Lifetime | 10,000 hours (mean time before failure), 1 year warranty | 10,000 hours (mean time before failure), 1 year warranty |
kSA MOS UltraScan Analysis Only Software Sentinel Key:
M-AOS option is an analysis-only software sentinel key that allows complete kSA MOS UltraScan functionality,
with the exception of data acquisition. It is designed for users who want to perform post acquisition, display,
processing and analysis away from the laboratory.
Installation and Training:
A minimum of 1-2 days of on-site customer installation are required with system purchase.
Warranty:
All kSA systems and integrated components are warranted against defective materials and workmanship for a
period of ONE YEAR from the date of delivery to the original purchaser.
kSA MOS UltraScan Integrated Software
The kSA MOS UltraScan data acquisition software controls and monitors all applicable hardware including laser, camera, servo-motor control mirror, XY scanning stage, and data acquisition boards. The software automatically detects the laser array, controls the camera exposure time to ensure no saturation as the surface reflectivity changes, and continuously centers the reflected array via real-time adjustment of the servo-controlled fold mirror as the sample is scanned.
The kSA MOS UltraScan software provides real-time plotting of differential spot spacing, curvature, reflectivity, bow height, film thickness (optional), film stress, and spectral reflectance (optional). Scanning recipes may be saved for easy measurement setup. For system calibration, the kSA MOS UltraScan automatically measures the calibration mirrors before sample scanning for fast, easy, and consistent calibration run after run. The multithreaded architecture of the kSA MOS UltraScan software allows you to analyze previously acquired data while a current scan is being performed. In addition, the complementary analysis only software license for post-deposition/acquisition analysis allows the user to analyze data at a separate location, if needed.
All kSA metrology software has a user-friendly Windows-standard environment with extensive error checking and file handling. It is user configurable so that each user’s preferred window layouts and acquisition/analysis preferences can be saved for future use. kSA metrology software allows data storage in ASCII, Excel or binary file formats, facilitating alternative data analysis if desired. Included in all kSA metrology software are highquality 2D and 3D graphics for data display and analysis, as well as numerous image and graphics editing capabilities, including false coloring using pre-loaded or user-defined color palettes, and label editing. Transport graphics directly to the Windows clipboard, or export to wmf, png, tiff, or bmp formats. For integration with other computer systems, complete TCP/IP interface for custom, real-time data transfer and program control, and data transfer to SQL databases is included.
1 | Live video image showing twelve reflected laser spots from the sample |
2 | Time-averaged curvature data |
3 | Real-time curvature map updated as data is taken, represented as a 2D data plot |
4 | Real-time curvature map updated as data is taken, represented as a 3D surface plot |
5 | Latest measured film thickness value (in microns) |
6 | Real-time spectral reflectance data with extrema identification for thickness determination |
7 | Real-time film thickness map updated as data is taken, represented as a 2D data plot |
8 | Real-time film thickness map updated as data is taken, represented as a 3D surface plot |
kSA software screen shot of multiple real-time measurements on a commercial GaN on Sapphire template
Distributors
k-Space has an expansive network of distributors to best serve our worldwide customer base.
HEADQUARTERS
k-Space Associates, Inc.
Michigan, USA
www.k-space.com
[email protected]
DISTRIBUTION PARTNERS
RTA Instruments Ltd.
Europe
www.rta-instruments.com
[email protected]
El Camino Technologies Pvt Ltd.
India
www.elcamino.in
[email protected]
Giant Force Technology Co., Ltd.
China
www.giantforce.cn
[email protected]
Jung Won Corporation
South Korea
www.jwc.co.kr
[email protected]
R-DEC Co.,Ltd.
Japan
Hong Kong
Taiwan
www.rdec.co.jp
[email protected]