Filmetrics F3-sX Optical Thick Film Thickness Gauge
Near-Infrared (NIR) Optical Thick Film Measurement System — 10μm micro-spot, measures up to 3mm thickness, 1kHz high-speed sampling
15nm～3mm Thickness measurement range (config dependent) | 10μm Minimum measurement spot | 1kHz Maximum measurement rate | 3 Wavelength configurations |
Product Introduction
Filmetrics F3-sX Optical Thick Film Thickness Gauge is a near-infrared (NIR) optical film thickness measurement system designed specifically for thick films and specialty materials. Using spectral reflectance principle and long-wavelength NIR light source, it can easily penetrate materials that appear opaque to the naked eye, measuring semiconductor and dielectric films up to 3mm thick. Compared to visible light reflectometers, the F3-sX's unique NIR technology is the key to thick film measurement and penetration of specific substrates such as silicon.
Thick film surfaces are typically rough and non-uniform, making large-spot traditional film thickness gauges inadequate. The F3-sX features a standard 10μm micro-spot that precisely focuses on micro-areas of the sample surface, easily measuring films that other thickness measurement instruments cannot detect, with measurements completed in a fraction of a second. The system supports measurement rates up to 1kHz and can be integrated into roll-to-roll (R2R) and other in-line processes for real-time film thickness monitoring. Three wavelength configurations are available: F3-s980 (cost-optimized), F3-s1310 (optimized for heavily doped silicon), and F3-s1550 (ultra-thick film), meeting diverse measurement needs from thick films to ultra-thick films, from conventional materials to heavily doped silicon wafers.
Core TechnologyF3-sX utilizes near-infrared spectral reflectance technology. NIR light has high penetration through semiconductor materials such as silicon, enabling direct measurement of wafer thickness and thick films on silicon substrates. The 1kHz high-speed sampling rate makes it an ideal film thickness monitoring tool for in-line processes like roll-to-roll — the only optical film thickness gauge that combines thick film, micro-area, and high-speed measurement.
Why Choose F3-sX? — Five Core Advantages for Thick Film Measurement
【NIR Penetration · Thick Films and Opaque Materials】Utilizing the long-wavelength characteristics of near-infrared (NIR) light to penetrate materials that visible light cannot pass through. Directly measure silicon wafer thickness, heavily doped silicon wafers, thick photoresists (such as SU-8), conformal coatings, and other films that appear opaque to the naked eye. Measurement range from 15nm to 3mm — a true optical thick film thickness gauge.
【10μm Micro-Spot · Accurate Measurement on Rough Thick Films】Thick film surfaces are often rough and non-uniform. Millimeter-scale large spots tend to cause measurement deviations due to signal averaging. The F3-sX features a standard 10μm micro-spot that focuses on micro-areas of the sample surface, easily handling rough thick films, curved surfaces, and irregular coatings, ensuring high accuracy and repeatability in thick film measurements.
【1kHz High-Speed Sampling · In-Line Process Integration】The F3-sX supports measurement rates up to 1kHz, enabling real-time film thickness monitoring in continuous motion processes such as roll-to-roll (R2R). Paired with optional automated mapping stages, it can quickly complete thickness distribution mapping over large-area thick films — a powerful tool for high-speed film thickness inspection on production lines and in R&D.
【Three Wavelength Configurations · Flexible Adaptation】The F3-sX series offers three wavelength configurations: F3-s980 is cost-optimized for general thick films; F3-s1310 is optimized for heavily doped silicon, ideal for semiconductor wafers and chip measurement; F3-s1550 is for ultra-thick films, with measurement range up to 3mm. Users can flexibly choose based on material type and thickness range for optimal cost-performance.
【Broadband Extension Option · Thin and Thick in One】The F3-sX offers an optional visible band extension (380-1050nm), extending the measurement lower limit from 15nm down to nanoscale ultra-thin films. A single device covers the full measurement range from ultra-thin optical coatings to 3mm thick films — ideal for laboratories or production lines with samples spanning multiple thickness ranges.
F3-sX vs F20 Comparison
Although both F3-sX and F20 use spectral reflectance, they are designed for completely different application scenarios. The F20 uses visible light (380-1050nm) and excels at rapid measurement of conventional transparent films. The F3-sX uses near-infrared (960-1580nm) and is specifically designed for thick films, silicon penetration, and opaque materials.
| Comparison Dimension | F3-sX Optical Thick Film Thickness Gauge | F20 Optical Film Thickness Gauge |
|---|
| Wavelength Range | Near-Infrared (960-1580nm) | Visible (380-1050nm) |
| Max Thickness | 3mm (config dependent) | 70μm |
| Core Advantage | Penetrates silicon/opaque materials, measures thick films and silicon wafers | Rapid measurement of conventional transparent film thickness and refractive index |
| Measurement Spot | 10μm micro-spot | 1.5mm standard spot |
| Typical Applications | Silicon wafer thickness, thick photoresist, conformal coatings, IC failure analysis | Semiconductor process films, optical coatings, polymer coatings |
Typical Thick Film Measurement Applications
The core value of the F3-sX lies in solving the "challenge of measuring thick films and specialty materials". For applications where visible light reflectometers fail — such as silicon wafer thickness, IC chip backside thinning, thick photoresist, conformal coatings — the F3-sX provides a unique solution through NIR penetration and micro-spot capability. The most typical application scenarios are:
| Application Area | Thick Film Measurement Scenario | Typical Measurement Objects |
|---|
| Silicon Wafer Thickness | Using NIR light to penetrate silicon wafers and measure total wafer thickness without damaging the sample. Ideal for thickness verification after wafer backside grinding, Taiko wafer thickness monitoring, and more. The F3-s1310 configuration is optimized for heavily doped silicon for accurate measurement of low-resistivity silicon wafers. | Silicon wafer thickness (after thinning), Taiko wafers, SOI silicon layer thickness |
| IC Chip Backside Thinning Failure Analysis | In IC failure analysis (FA), precise measurement of remaining silicon thickness after chip backside thinning is required. The F3-sX's 10μm spot can precisely locate specific chip areas, and NIR penetration enables direct measurement of silicon layer thickness, providing critical data for FA. | Remaining chip silicon thickness, backside thinning uniformity |
| Thick Photoresist & SU-8 | Thick photoresists such as SU-8 are widely used in MEMS and microfluidic devices, typically tens to hundreds of microns thick. The F3-sX's NIR band easily penetrates thick resist layers, and the 10μm spot measures local resist thickness within microstructures — ideal for thick photoresist thickness measurement. | SU-8 photoresist, thick polyimide, dry film photoresist |
| Conformal Coatings & Encapsulation Materials | Thickness measurement of conformal coatings on PCB boards and electronic components. The F3-sX's non-contact measurement and micro-spot capability enable precise measurement of coating thickness on curved areas such as device pins and solder joints. | Polyurethane conformal coating, silicone coating, parylene thick coatings |
| Compound Semiconductors & MEMS | Thickness measurement of compound semiconductor substrates such as gallium arsenide (GaAs) and silicon carbide (SiC), as well as characterization of thick silicon layers, thick aluminum nitride films, and other structural layers in MEMS devices. | GaAs/SiC substrate thickness, MEMS thick silicon layers, AlN piezoelectric films |
| Roll-to-Roll (R2R) In-line Thickness Monitoring | In roll-to-roll coating or deposition processes on flexible substrates, the F3-sX's 1kHz high-speed sampling capability enables real-time in-line thickness monitoring of moving substrates, meeting process control requirements for flexible electronics, thin-film solar cells, and more. | Flexible substrate coating thickness, thin-film solar cell layers, barrier films |
Measurement Principle
The F3-sX uses spectral reflectance with near-infrared (NIR) light for non-contact film thickness measurement. NIR light illuminates the sample surface, reflecting off the upper and lower interfaces of the film. The two reflected beams interfere due to optical path differences, producing an interference spectrum. By analyzing the oscillation frequency of the interference spectrum, the system precisely calculates film thickness within seconds while also deriving optical constants such as refractive index (n). Compared to visible light reflectometers, the longer wavelength of NIR provides better interference fringe recognition for thick film measurement, while also offering high penetration through semiconductor materials such as silicon for direct measurement of wafer thickness and thick films on silicon substrates.
F3-sX Series Selection Guide
The F3-sX series offers three wavelength configurations, differing mainly in wavelength range, thickness measurement range, and applicable materials. As a general rule: longer wavelengths measure thicker films and better penetrate heavily doped silicon.
| Model | Wavelength Range | Thickness Range (n=1.5) | Thickness Range (n=3.5) | Typical Applications |
|---|
| F3-s980 | 960 – 1000nm | 15μm – 1.5mm | 7μm – 0.7mm | Cost-optimized, general thick film measurement |
| F3-s1310 | 1280 – 1340nm | 15μm – 2mm | 7μm – 1mm | Optimized for heavily doped silicon, silicon wafer and chip thickness measurement |
| F3-s1550 | 1520 – 1580nm | 15μm – 3mm | 7μm – 1.5mm | Ultra-thick film measurement (up to 3mm), extreme thick film applications |
Not sure which configuration to choose? Contact an engineer for recommendations
Product Parameters
| Product Model | F3-sX (F3-s980 / s1310 / s1550) | Measurement Technology | NIR Spectral Reflectance |
| Wavelength Range | 960-1000nm (s980) / 1280-1340nm (s1310) / 1520-1580nm (s1550) | Light Source | Long-life LED (>200,000 hours MTBF) |
| Thickness Range (n=1.5) | 15μm – 1.5mm / 2mm / 3mm (model dependent) | Thickness Range (n=3.5) | 7μm – 0.7mm / 1mm / 1.5mm (model dependent) |
| Measurement Accuracy | 5nm | Measurement Spot | 10μm (minimum) |
| Working Distance | 53mm (standard) | Measurement Rate | Up to 1kHz |
| Material Database | 130+ built-in, expandable | Software | FILMeasure (one-click analysis) |
| Optional Accessories | Automated mapping stage, measurement point visualization camera, visible band extension (380-1050nm), roll-to-roll process integration kit |
| For more parameters and custom configurations, please contact us |
Actual Test Data Display
Customer Reviews
"The F3-s1310 is an invaluable tool in our IC failure analysis laboratory. For thickness measurement of backside-thinned chips, the NIR penetration capability allows us to accurately measure remaining silicon thickness without damaging samples. The 10μm spot can target individual chip areas, delivering accurate and reliable results that have completely replaced our previous cross-section SEM method, improving efficiency by orders of magnitude."
—— Failure Analysis Laboratory, Semiconductor Chip Design Company
"The F3-sX solved our thick photoresist process measurement challenge. SU-8 resist thickness often ranges from tens to hundreds of microns, which conventional visible light reflectometers struggle to measure accurately. The F3-s1550's NIR band and 10μm spot perfectly addressed this. We also use the F3-sX for in-line film thickness monitoring on our R2R production line, and the 1kHz sampling rate keeps up with line speed. Highly recommended for anyone needing thick film measurement."
—— Process R&D Department, MEMS Device Manufacturer
Frequently Asked Questions (FAQ)
What is the core difference between F3-sX and F20?
Both use the same spectral reflectance principle, but their light source bands and application scenarios are completely different. The F20 uses visible light (380-1050nm) and is suitable for measuring conventional transparent films with thickness range of approximately 15nm-70μm. The F3-sX uses NIR light (960-1580nm) that can penetrate semiconductor materials like silicon, measuring thick films up to 3mm with a 10μm micro-spot for rough surfaces. If you need to measure silicon wafer thickness, thick photoresist, conformal coatings, or IC chip backside thinning, the F3-sX is the only choice.
How to choose among the three F3-sX models?
Selection is primarily based on film thickness range and material type: F3-s980 is cost-optimized for general thick film measurement (up to 1.5mm); F3-s1310 is optimized for heavily doped silicon, with wavelength located in silicon's transmission window for accurate measurement of low-resistivity silicon wafers — the top choice for semiconductor industry; F3-s1550 has the longest wavelength with measurement range up to 3mm for ultra-thick film applications. General rule: the thicker the film or more opaque the material, the longer the wavelength needed. Contact application engineers for professional selection guidance.
What is the advantage of the F3-sX's 10μm spot?
Thick film surfaces are typically rougher than nanoscale films. Millimeter-scale large spots cause measurement signals to average out due to surface height variations, reducing accuracy. The F3-sX's 10μm micro-spot focuses on micro-areas of the sample surface, effectively avoiding interference from surface roughness to ensure accuracy and repeatability of thick film measurements. The micro-spot is also ideal for applications requiring precise positioning on chip areas and MEMS microstructures.
Can the F3-sX measure silicon wafer thickness?
Yes — this is one of the F3-sX's core capabilities. NIR light has high penetration through silicon, directly measuring wafer thickness. The F3-s1310 configuration (1280-1340nm) is optimized for heavily doped silicon, accurately measuring low-resistivity silicon wafer thickness. This capability is invaluable for wafer backside grinding process monitoring, Taiko wafer thickness measurement, and IC chip failure analysis.
What are the applications of the F3-sX's 1kHz high-speed sampling?
1kHz high-speed sampling enables the F3-sX to be integrated into continuous motion processes such as roll-to-roll (R2R) for real-time in-line film thickness measurement of moving substrates. Additionally, in production line scenarios requiring rapid inspection of large sample volumes, the 1kHz sampling rate significantly increases throughput — the ideal choice for high-speed in-line film thickness monitoring.
Can the F3-sX be upgraded with visible band extension?
Yes. The F3-sX offers an optional visible band extension (380-1050nm), extending the measurement lower limit from 15nm (NIR) down to nanoscale ultra-thin films in the visible range. A single device covers the full measurement range from ultra-thin optical coatings to 3mm thick films — ideal for comprehensive laboratories or production lines handling samples across multiple thickness ranges.
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View Details →Free Sample Testing Service
Free Sample Testing Service
Not sure if your thick film or silicon wafer sample is suitable for F3-sX NIR measurement? We offer free sample testing services! Send us your samples, and our professional engineers will use the F3-sX for thick film thickness testing, providing detailed measurement reports and selection recommendations.
