Reflection Spectrophotometry for Photovoltaic Applications
FilmTek™ Solar is an accurate and economical film thickness measurement system that is designed specifically for textured substrates. Unlike competing ellipsometer designs, no special stage tilting or sample alignment is necessary with FilmTek™ Solar. By combining a small measurement spot size with a large collection angle, superb signal to noise is obtained for rough and textured substrates without sample alignment. FilmTek™ software automatically models multiple reflections from textured monocrystalline silicon substrates to provide accurate film measurements. The FilmTek™ Solar is especially well suited for measuring anti-reflective coatings on textured silicon substrates (e.g., silicon nitride films deposited on monocrystalline silicon and polycrystalline silicon substrates).
FilmTek™ software includes fully user-customizable mapping capabilities to rapidly generate 2D and 3D data maps of any measured parameter. In addition to user-defined patterns, standard map patterns include polar, X-Y, rθ, or linear.
The FilmTek™ Integrating Sphere measures the total integrated reflectance of flat surfaces placed against the sphere’s 10.3 mm sample port. Illumination is provided by an internal tungsten halogen lamp, which is baffled such that incident light on the sample has been reflected from the sphere walls. The sphere’s highly Lambertian interior provides a uniform 180° illumination field. A manual switch allows the measurement of diffuse reflectance or specular and diffuse reflectance. The FilmTek™ Integrating Sphere is ideal solution for measuring total integrated reflectance and film thickness for photovoltaic applications.
For thin film photovoltaic applications, we recommend the FilmTek™ 2000 and FilmTek™ 3000 systems for characterization of the band gap, layer thicknesses, and rough interfacial layers critical for maximizing photovoltaic device efficiency.
Measurement Capabilities:
FilmTek™ Solar incorporates SCI’s generalized material model with advanced global optimization algorithms for simultaneous determination of:
- Multiple layer thicknesses
- Indices of refraction [ n(λ) ]
- Extinction (absorption) coefficients [ k(λ) ]
Low Cost
The cost of ownership of a FilmTek™ Solar is a small fraction of comparable instruments.
Intuitive
FilmTek™ Solar software is designed so that minimal experience in thin film optical design or measurement techniques is required.
Hardware
FilmTek™ Solar/ Integrating Sphere includes:
- UV/VIS/NIR spectrophotometer
- UV/VIS/NIR light source
- Fiber optic cables
- Automated stage with optics
- Computer with multi-core processor running Windows™ 10 Operating System
| FilmTek™ Solar Technical Specifications | |||
|---|---|---|---|
| Film thickness range: | 3nm-150µm | ||
| Film thickness accuracy: | ±2Å for NIST traceable standard oxide 1000Å to 1µm | ||
| Spectral range: | 240nm-950nm | ||
| Measurement spot size: | 1mm | ||
| Sample size: | 2mm to 156mm standard | ||
| Spectral resolution: | 0.3nm | ||
| Light source: | Regulated deuterium-halogen lamp (2,000 hrs lifetime) | ||
| Detector type: | 2048 pixel Sony linear CCD array | ||
| Reflection static repeatability @ 600nm (1s): | 0.01% | ||
| Measurement time: | <1 sec per site (e.g., oxide film) | ||
| Data acquisition time: | 0.2 sec | ||
| Computer: | Multi-core processor with Windows™ 10 Operating System | ||
| FilmTek™ Integrating Sphere Technical Specifications | |||
|---|---|---|---|
| Film thickness range: | 10nm-50µm | ||
| Film thickness accuracy: | ±2Å for NIST traceable standard oxide 1000Å to 1µm | ||
| Spectral range: | 380nm-950nm | ||
| Measurement spot size: | 10.3 mm | ||
| Sample size: | 15mm to 300mm standard | ||
| Spectral resolution: | 0.3nm | ||
| Light source: | Regulated tungsten-halogen lamp (900 hrs lifetime) | ||
| Detector type: | 2048 pixel Sony linear CCD array | ||
| Reflection static repeatability @ 600nm (1s): | 0.01% | ||
| Measurement time: | <1 sec per site (e.g., oxide film) | ||
| Data acquisition time: | 0.2 sec | ||
| Computer: | Multi-core processor with Windows™ 10 Operating System | ||
| Performance Specifications | |||
|---|---|---|---|
| Film(s) | Thickness | Measured Parameters | Precision (1σ) |
| Oxide / Si | 100-10,000 Å | t | 0.5 Å |
| Nitride / Si | 100-10,000 Å | t | 0.5 Å |