The Zeta™-300 optical profiler offers 3D metrology and imaging, with an integrated isolation table and design flexibility for larger samples. The 3D optical metrology system uses ZDot™ technology to acquire high-resolution 3D data and True Color infinite focus images.
Thanks to its multi-mode optics, simple software, and low ownership costs, the Zeta-300 non-contact profiler is suitable for both R&D and production scenarios.
Product Details
Product Description
Image Credit: KLA Instruments™
The Zeta-300 optical profiler is an advanced non-contact, 3D surface topography measurement system, building upon the features of the Zeta-20 profiler. It includes enhanced isolation options and the flexibility to accommodate larger samples. This 3D optical metrology system leverages patented ZDot technology and Multi-Mode optics, allowing for the measurement of diverse sample types, ranging from transparent to opaque and smooth to rough textures, with step heights from nanometers to millimeters.
This versatile, non-contact measurement system integrates six different optical metrology technologies into a single, user-friendly platform. The ZDot measurement mode provides simultaneous high-resolution 3D optical scans and True Color infinite focus imaging. Additional 3D optical metrology techniques include white light interferometry, phase-shifting interferometry, Nomarski interference contrast microscopy, and shearing interferometry.
For film thickness measurement, the system utilizes ZDot technology or an integrated broadband reflectometer. Beyond metrology, the Zeta-300 serves as a high-end microscope suitable for sample review or automated defect inspection, supporting both R&D and production environments with its comprehensive capabilities in step height, roughness, film thickness measurements, and defect inspection.
Features
- ZDot and Multi-Mode optics combined with an intuitive optical profiler to handle a variety of applications
- ZDot: Concurrently collects an infinite focus image in true Color and a high-resolution 3D scan
- Zeta phase and Vertical Scanning Interferometry (PSI and VSI) allow high z-resolution large area observations
- ZIC: Interference contrast for numerical three-dimensional data of surfaces with roughness below the nanometer
- ZSI: Shearing interferometry for high-z resolution images
- ZFT: An integrated broadband reflectometer is used to measure the thickness and reflectance of films
- AOI: Automated optical inspection to measure sample flaws
- Production capacity: Completely automated measurements with pattern recognition and sequencing
Image Credit: KLA Instruments™
Applications
- Defect inspection: Capture defects larger than 1 µm
- Defect review: KLARF files are used to navigate to defects to measure 3D surface topography or scribe defect locations
- Form: 3D bow and shape
- Film thickness: Transparent film thickness from 30 nm to 100 µm
- Step height: 3D step height from nanometers to millimeters
- Stress: 2D thin film stress
- Texture: 3D roughness and waviness on smooth to very rough surfaces
Image Credit: KLA Instruments™
Industries
- PCB (printed circuit board) and flexible PCB
- MEMS: Micro-electro-mechanical systems
- Medical devices and microfluidic devices
- Data storage
- Universities, research labs and institutes
- LED: Light emitting diodes and PSS (patterned sapphire substrates)
- Semiconductor and compound semiconductor
- Semiconductor WLCSP (wafer-level chip scale packaging)
- Semiconductor FOWLP (fan-out wafer-level packaging)
Image Credit: KLA Instruments™
Applications
Step Height
The Zeta-300 3D non-contact optical profiler can measure three-dimensional non-contact step heights ranging from nanometers to millimeters. ZDot and Multi-Mode optics offer several approaches for determining the step height. The main measuring method, ZDot, can measure increments from tens of nanometers to millimeters instantaneously.
ZI interferometry can be utilized to measure steps from nanometers to millimeters for a wide range of measurements. Measurements in steps smaller than 80 nm can be made using ZSI shearing interferometry.
Image Credit: KLA Instruments™
Film Thickness
The Zeta-300 optical profiler can determine the thickness of a transparent film or films using ZDot or ZFT measurement methods. ZDot is employed for measuring transparent films larger than 10 µm, including photoresists or layers of microfluidic devices placed on substrates with a higher refractive index.
ZFT measures films ranging in thickness from 30 nm to 100 µm using a built-in broadband reflectometer. The user can enter the parameters of the film or use a model to fit the spectrum to accomplish this for a single or multiple-layer film stack
Image Credit: KLA Instruments™
Texture: Roughness and Waviness
The Zeta-300 3D profiler quantifies a sample's roughness and waviness by measuring its 3D texture. ZDot can measure roughness ranging from tens of nanometers to very rough surfaces. ZSI and interferometry make measurements of smooth surfaces, from angstroms to microns, possible.
Software filters compute characteristics like root mean square (RMS) roughness by separating the data into components of roughness and waviness. By displaying minute variations in slope, Nomarski interference contrast microscopy makes it possible to see incredibly tiny surface details.
Image Credit: KLA Instruments™
Form: Bow and Shape
The Zeta-300 non-contact profiler is capable of assessing both 2D and 3D contours or the curvature of a surface. This tool is particularly useful for measuring wafer bow, which may occur due to layer misalignment in the manufacturing of semiconductor or compound semiconductor devices. Additionally, the Zeta-300 can determine the three-dimensional height and curvature radius of various structures, including lenses.
Image Credit: KLA Instruments™
Stress: Thin Film Stress
The Zeta-300 is able to measure the stress that is created when multilayer devices, such as semiconductors or compound semiconductors, are manufactured. Using a stress chuck to hold the sample in a neutral position, the bow of the surface can be precisely determined. The stress is then determined by using the concepts of Stoney’s equation and the shape change resulting from a process like film deposition.
To calculate 2D stress, the Zeta-300 records the sample surface height at user-specified intervals along the whole sample diameter. The data is then combined to create a profile of the sample shape.
Image Credit: KLA Instruments™
Automated Defect Inspection
The Zeta-300 is equipped with Automated Optical Inspection (AOI) capabilities, allowing for fast inspection of samples, differentiation of various defect types, and mapping of defect density across the sample. When integrated with its 3D metrology functionality, the Zeta-300 offers enhanced insights into defects that surpass what is achievable with conventional 2D inspection systems. This integration facilitates faster and more accurate identification of the sources of defects.
Image Credit: KLA Instruments™
Defect Review
The Zeta-300 defect review process uses a KLARF file from the inspection tool to guide the stage to specific defect locations. Users can then either observe the defect using a high-resolution microscope or measure its topography, such as height, thickness, or texture, for more detailed analysis not possible with 2D inspection systems.
Additionally, the Zeta-300 can mark defects with a scribe, facilitating their identification on devices like SEM review tools, which have a restricted field of view
Image Credit: KLA Instruments™
LED Pattern Sapphire Substrates (PSS)
The Zeta-300 optical profiler enables metrology and examination of patterned sapphire surfaces. The technology uses ZDot, through-sample lighting, and unique algorithms to swiftly determine the height, width, and pitch of PSS bumps.
The Zeta-300 can also be used to evaluate photoresist before and after patterning, allowing for sample rework before sapphire etch. Automated defect inspection of PSS substrates allows for the quick detection of significant flaws such as missing PSS bumps, bump bridging, tear-out, and contamination.
Image Credit: KLA Instruments™
Semiconductor and Compound Semiconductor Packaging
The Zeta-300 is equipped to meet the metrology requirements of Wafer-Level Chip Scale Packaging (WLCSP) and Fan-Out Wafer Level Packaging (FOWLP). Its advanced technology allows for the measurement of copper height with an intact dry photoresist film. This is achieved by measuring through the transparent photoresist down to the seed layer to assess the copper pillar height, photoresist thickness, and the relative height difference between the copper and photoresist.
The Zeta-300 also facilitates the measurement of redistribution lines (RDL), under bump metallization (UBM) height and texture, critical dimensions of photoresist openings, photoresist and polyimide thickness. Additionally, it can measure the coplanarity of metal contacts to ensure that the bump height aligns with the connectivity requirements of the final device packaging.
Image Credit: KLA Instruments™
Printed Circuit Board (PCB) and Flexible PCB
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The Zeta-300 boasts a high dynamic range that facilitates the measurement of surface roughness and step heights ranging from nanometers to millimeters without needing to change its configuration. It is adept at managing both high-reflectance films, like copper, and transparent films typically used on PCBs.
Additionally, the Zeta-300 supports critical dimension measurements, including height and width, for features such as blind via holes, line traces, and hot bars, along with assessing surface roughness.
Laser Ablation
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The Zeta-300 is capable of measuring topographical changes caused by laser surface processing on semiconductors, LEDs, microfluidic devices, PCBs, and other materials. Lasers are used for precise micro-scale machining and surface conditioning in sectors such as semiconductors, LEDs, and biomedical equipment.
In the semiconductor business, measuring the height and width of a wafer ID mark is crucial to guarantee that it can be read effectively throughout several processing stages.
Microfluidics
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The Zeta-300 is equipped to measure microfluidic devices made from materials such as silicon, glass, and polymers. The system accurately quantifies critical dimensions, including the height, width, edge profile, and texture of channels, wells, and control structures.
Additionally, the Zeta-300 can measure the device after it has been sealed with a transparent top cover plate, adjusting for changes in refractive index and quantifying the stress-induced changes resulting from the application of the cover plate.
Biotechnology
Image Credit: KLA Instruments™
The Zeta-300 is ideal for biotechnology applications because it allows non-contact measurement of a wide range of sample surfaces with dimensions ranging from nanometers to millimeters. The Zeta-300 can detect high aspect ratio steps, such as the depth of deep wells used in biotech devices.
Micro-needle array structures for drug administration can be tested using the high numerical aperture objective lens and the capacity to resolve a sample with extremely low reflectance.
Options
The Zeta™-300 Optical Profiler offers optional features that can be added to the new product or in the future.
ZFT: Zeta Film Thickness
Image Credit: KLA Instruments™
The Zeta-300 features an integrated broadband spectrometer designed for measuring the thickness of transparent thin films ranging from 30 nm to 100 µm. It supports thickness measurements for both single-layer and multi-layer film stacks, allowing users to select refractive index values from a pre-established material library. Additionally, it can map the film thickness across a sample to assess its uniformity.
The Zeta-300 is also effective on surfaces with low reflectivity, such as surfaces with less than 0.1 % reflectance. Where many film thickness measurement tools struggle to detect signals from such low-reflectance surfaces, which rely on specular reflection to gauge phase changes or other parameters, the Zeta-300 overcomes these challenges. Its use of broadband white light and normal incidence illumination makes it versatile for a variety of optically transparent films with minimal reflectance
ZI: Zeta Interferometry
Image Credit: KLA Instruments™
The Zeta-300 is equipped to support both Phase Scanning Interferometry (PSI) and Vertical Scanning Interferometry (VSI) when used in conjunction with a piezo stage and an interferometric objective lens. PSI is designed for rapid measurement of step heights ranging from angstroms to hundreds of nanometers.
Conversely, VSI, also recognized as White Light Interferometry (WLI), allows for the measurement of step heights extending from hundreds of nanometers to hundreds of microns. Both methods achieve resolutions better than a nanometer, regardless of the numerical aperture of the objective lens.
ZIC: Zeta Interference Contrast
Image Credit: KLA Instruments™
Nomarski differential interference contrast microscopy is used by the Zeta-300 to improve fine surface detail imaging. Nomarski microscopy highlights variations in slope on the sample surface by using polarization and a prism to alter the phase. This makes it possible to see flaws in extremely smooth surfaces, like a monolayer of a contaminant.
By comparing the change in slope with roughness recorded using an alternative method, the ZIC scanning mode can turn these images into quantitative measures of sub-nanometer level roughness.
ZSI: Zeta Shearing Interferometer
Image Credit: KLA Instruments™
By introducing a phase shift, the Zeta-300 shearing interferometer measurement technique (ZSI) improves the ZIC measurement. Several steps of image acquisition are employed, followed by sophisticated algorithms for processing, to produce a quantitative measurement of surface topography with resolution down to the angstrom level. This method yields high-resolution measurements from angstroms to 80 nm without the need for interferometric objectives or Z-stage scanning.
ProfilmOnline Web Application
Image Credit: KLA Instruments™
Filmetrics ProfilmOnline is a cloud-based platform for 3D data visualization and analysis, part of the Profilm software suite. It serves as a centralized location to share, store, view, and analyze 3D data, accessible from both computers and mobile devices. The platform offers dedicated apps for Android and iOS operating systems, supports a wide range of file formats, and features data encryption to ensure security.
Objective Lenses
Image Credit: KLA Instruments™
There is a wide variety of objective lenses available, such as through transmissive, liquid immersion, vertical scanning interferometry, refractive index corrected, long working distance, ultra-long working distance, and 2.5× – 150× normal objectives.
Couplers
Image Credit: KLA Instruments™
The optics magnification of the Zeta-300 can be adjusted by combining four different optical coupler configurations. To maintain the original magnification, the system may be set up with a 1× coupler; alternatively, it can be set up with 0.35×, 0.5×, or 0.63× couplers to enhance the magnification.
Objective Lens Turret
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The Zeta-300 allows for customization with either a 5 or 6-position manual turret, which includes an objective lens sensor for automatic identification of objectives. Additionally, the system can be equipped with a 5 or 6-position motorized turret, enabling fully automated operations.
Sample Lighting
Image Credit: KLA Instruments™
The Zeta-300's standard lighting consists of dual high-brightness white LEDs. Backlighting through the sample chuck is also provided to improve lighting for difficult transparent samples such as patterned sapphire substrates (PSS). The Zeta-300 also has darkfield lighting from the side.
Stages
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The Zeta-300 offers flexible configuration options with various stages to enhance its system performance. It can be equipped with a piezo Z-axis stage to enhance Z resolution, which is ideal for measuring nanometer-level step heights in ZDot or ZI measurement modes. Additionally, an optional 280 mm Z tower is available to accommodate larger items such as tablets, phones, and bulky machine components.
For the XY stage, options include a manual version with up to 300 mm travel or a motorized version offering 150 mm or 200 mm travel. Furthermore, a manual rotary stage can be integrated with the XY stage, and a manual tip and tilt stage can be added to precisely level the stage for interferometry measurements.
Sample Chucks
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The Zeta-300 offers a variety of chucks tailored to meet specific application needs. Backlight chucks are available for transparent substrates to facilitate transmitted illumination, which is necessary for patterned sapphire substrates. The system supports various wafer sizes, including 300 mm, and offers multiple sample chucks.
Isolation Tables
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The Zeta-300 incorporates passive isolation within its base. For scenarios demanding enhanced isolation, an active isolation table is offered. Additionally, the system can be equipped with an acoustic enclosure to shield against environmental noise, improving its capability to measure nanometer-level steps and surface roughness.
Step Height and Film Thickness Standards
Image Credit: KLA Instruments™
The Zeta-300 utilizes both thin and thick film NIST traceable step height standards provided by VLSI Standards, featuring an etched quartz step coated with chrome. These standards cover a step height range from 8 nm to 250 µm.
A certified multi-step standard with nominal step heights of 8, 25, 50, and 100 µm is also available, which includes various pitch patterns for XY calibration. There is a certified film thickness standard for ZFT that includes a reference silicon surface and a nominal silicon dioxide film thickness of 270nm. Reference roughness and mirror samples are also available.
Automated Sequencing Software
Image Credit: KLA Instruments™
The automated sequencing software leverages the motorized XY stage, enabling users to program measurement locations on the sample. The system automatically measures each site and saves the results in user-defined folders, generating an output report that summarizes the sample statistics.
Advanced sequencing software incorporates pattern recognition to automatically align the sample, facilitating fully automated measurements and reducing operator error. Auto-calibration can also be activated using embedded standards on the stage.
Stitching Software
Image Credit: KLA Instruments™
Automated image stitching software employs the motorized XY stage to merge adjacent scans into a larger stitched data set than a single field of view could provide. The system measures each site, aligns the images, and integrates them into a single data set for analysis.
Apex Analysis Software
Image Credit: KLA Instruments™
Apex analysis software expands the tool's standard data analysis capabilities with an extensive array of leveling, filtering, step height, roughness, and surface topography analysis techniques. Apex supports ISO roughness calculation methods and local standards such as ASME. It also functions as a report-writing platform, enabling the addition of text, annotations, and pass/fail criteria. Apex is available in eleven languages.
Offline Analysis Software
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The offline analysis software of the Zeta-300 maintains the same data analysis and recipe creation functions available on the tool, allowing users to create recipes and analyze data without occupying the tool during operational hours.