Undoped Silicon Wafers for FTIR Spectroscopy
UniversityWafer supplies high-resistivity undoped silicon wafers for Fourier-Transform Infrared Spectroscopy (FTIR), attenuated total reflection (ATR-FTIR), semiconductor research, thin-film characterization, and advanced materials science.
One of our most popular substrates for FTIR applications is:
Silicon Item #3193
100 mm Undoped <100> | >10,000 Ω·cm | 525 μm | Double-Side Polished (DSP) | Prime Grade
High-resistivity undoped silicon provides an excellent substrate for infrared spectroscopy because of its polished surface, electrical properties, and compatibility with semiconductor processing and thin-film deposition.
Undoped Silicon for Lithium-Ion Battery Research
Silicon is a promising anode material for next-generation lithium-ion batteries (LIBs) because of its exceptionally high theoretical capacity. One challenge, however, is capacity fade caused by repeated expansion and contraction during charge-discharge cycling.
Researchers believe this degradation is largely associated with the formation and instability of the solid electrolyte interphase (SEI), which develops on the silicon surface during the first charging cycle.
A research team selected Silicon Item #3193 for in situ attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) to study the chemistry occurring at the electrode-electrolyte interface while controlling infrared penetration depth.
Need an FTIR substrate? Buy Online or request a custom quote.
FTIR Spectroscopy Video
Learn how Fourier-Transform Infrared Spectroscopy (FTIR) is used for solid sample analysis, molecular identification, thin-film characterization, and semiconductor materials research.
What is Fourier Transform Infrared Spectroscopy?
Fourier Transform Infrared Spectroscopy (FTIR) is an analytical technique used to identify chemical bonds, molecular structure, surface chemistry, thin films, coatings, and contaminants by measuring how a sample absorbs infrared light.
FTIR spectroscopy is widely used in semiconductor research, materials science, lithium-ion battery studies, polymer analysis, chemical identification, failure analysis, and quality control. Researchers often use undoped high-resistivity silicon wafers as substrates for infrared measurements because they provide a clean, polished, semiconductor-grade surface.
How FTIR Spectroscopy Works
In FTIR analysis, infrared light passes through or reflects from a sample. Different chemical bonds absorb different infrared wavelengths, producing a spectrum that acts like a molecular fingerprint. Scientists use this spectrum to identify materials, detect contaminants, study thin films, and monitor chemical changes at surfaces and interfaces.
Common FTIR Applications
- Thin-film and coating analysis
- Semiconductor wafer surface characterization
- Polymer and plastic identification
- Contamination and failure analysis
- Battery electrode and electrolyte studies
- Oxide, nitride, and organic film measurements
- ATR-FTIR analysis of surface chemistry
Silicon Wafers for FTIR Measurements
Silicon wafers are commonly used in FTIR spectroscopy because they are flat, polished, chemically stable, and compatible with semiconductor processing. For infrared measurements, researchers often choose undoped silicon, high-resistivity silicon, or double-side polished silicon wafers depending on the experiment.
Why Use Undoped Silicon for FTIR?
- Low electrical interference: Undoped silicon is useful when researchers need minimal dopant-related effects.
- High resistivity: High-resistivity silicon supports infrared and spectroscopy research.
- Polished surfaces: DSP wafers help improve optical contact and measurement consistency.
- Research compatibility: Silicon wafers are widely used for thin films, coatings, and electrode studies.
FTIR for Lithium-Ion Battery Research
FTIR spectroscopy can be used to study the chemistry of lithium-ion battery materials, including the solid electrolyte interphase (SEI) that forms on silicon electrodes. Researchers use FTIR and ATR-FTIR methods to investigate chemical changes at the electrode-electrolyte interface during cycling.
High-resistivity undoped silicon wafers are useful for these experiments because they provide a controlled substrate for studying surface reactions, thin films, and interface chemistry.
Wafers Used for Infrared Spectroscopy
FTIR and infrared spectroscopy applications may require different wafer materials depending on the wavelength range, surface finish, coating, and optical requirements. Common wafer and substrate materials include:
- Silicon wafers for semiconductor and surface studies
- High-resistivity silicon wafers for infrared research
- Fused silica wafers for optical transmission applications
- Quartz wafers for optical and spectroscopy research
- Sapphire wafers for high-temperature and optical applications
FTIR vs. Raman Spectroscopy
FTIR spectroscopy and Raman spectroscopy are complementary analytical techniques. Both are used to identify materials, study molecular structure, and characterize unknown samples, but they measure different light-matter interactions.
- FTIR: Measures infrared absorption and is useful for identifying functional groups, chemical bonds, films, polymers, and surface chemistry.
- Raman: Measures scattered light and is useful for studying crystal structure, carbon materials, transparent samples, stress, and 3D depth profiling.
Many researchers use both techniques together because FTIR provides strong information about molecular absorption while Raman spectroscopy provides complementary structural information.
Watch an FTIR and Raman comparison video