CryoSAS: Cryogenic Silicon Analysis System
The Bruker Optics` Cryogenic Silicon Analysis System (CryoSAS) is a dedicated all-in-one system for the low temperature (<15K) impurity analysis of Silicon. CryoSAS is optimized for operation in the industrial environment.
CryoSAS combines Bruker's high performance FT-IR spectrometers with built-in, closed-cycle cryo-cooling technique that does not require any liquid Helium. All CryoSAS components are state-of-the-art, yet utilize proven technologies to accomplish a difficult analysis in the demanding silicon production environment. CryoSAS can be operated at a high level of automation including accurate reporting of the analysis results.
CryoSAS analyzes shallow impurities (e.g. Boron, Phosphorous etc.) down to the low ppta level according to the ASTM/SEMI MF1630 standard. Furthermore it simultaneously analyzes Carbon and Oxygen down to the low ppba level according to the ASTM/SEMI MF1391 standard.
CryoSAS Messergebnisse für Kohlenstoff (siehe oben) sowie für die flachen Störstellen Bor und Phosphor (siehe unten) bei tiefen Temperaturen (~12 K)
CryoSAS measurement results for carbon (see above) as well as for Boron and Phosphorus (see below) at low temperatures (~12 K).
Closed-cycle cryogenic refrigeration system: no expensive liquid cryogens needed
Highly reliable closed cycle cryo-cooling system for detector and sample chamber cooling. Compared to a liquid Helium cooled refrigeration system, the closed cycle system can save 50,000 € operation costs per year and even more.
CryoSAS low temperature sample compartment with automated 9 position sample holder.
CryoSAS main software screen displaying the currently loaded samples and the chosen analysis methods.
Stainless steel sample chamber design:
easy sample access
Proven sample chamber design with stationary optics and automated sample head. The large inner diameter of the sample chamber allows for easy sample holder access.
Dry fore pump and turbo pump:
simple and clean vacuum system operation
Fast and reliable evacuation via turbodrag pump and dry fore pump.
Robust, precision stepper motor stage with nine position sample holder:
The sturdy translation stage interfaced to the sample holder allows multiple sample analysis. The high torque motor and solid translation mechanism provide precise sample indexing and years of reliable functionality. Samples are easy to install and remove and the sample holder is nearly effortless to attach in the sample chamber. Gold-coated OFHC copper design of the sample holder ensures uniform temperatures.
Ease of use:
CryoSAS is optimized for operation in the industrial environment. All vacuum and refrigeration devices are controlled by a PLC. Cooling down and starting the measurement is a simple push button operation. The user does NOT have to be a spectroscopy expert or a vacuum expert.
The dedicated CryoSAS software is designed to fulfil the needs of industrial quality control. It is easy to use and can be operated via touch screen. The user simply has to choose the desired analysis method, enter the sample informations and press the start button. CryoSAS will then automatically cool down the samples, start the infrared measurement, evaluate the results and create an analysis report.
Spectral range: 1500 – 280cm-1 optimized for the detection of
- group III and V shallow impurities in single crystal Si according to ASTM/SEMI MF1630. For wedged samples with a thickness of approx.
3mm, the following detection limits can be reached:
- 10ppta Phosphorus
- 30ppta Boron
- substitutional Carbon according to ASTM/SEMI
MF1391. This method requires a Carbon free
FZ reference sample with thickness and surface
properties comparable to the sample specimen.
For a wedged sample with a thickness of approx. 3mm, Carbon
concentrations down to 20ppba can be detected.
Technologies used are protected by one or more of the following patents: US 5309217;
DE 4212143; US 7034944; US 5923422; DE 19704598