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Radiation Monitoring System Cutting-Edge Technology for Accurate Radiation Detection and Measurement We are dedicated to delivering state-of-the-art radiation monitoring systems that cater to the varied requirements of industries necessitating precise radiation detection and measurement. Our extensive product portfolio, including devices like the SmartKONT contamination monitor and the SmartRAY2 high-range dose rate meter, ensures safety and regulatory compliance across a multitude of applications. By integrating advanced technology with user-centric design, we provide reliable solutions that uphold the highest standards of performance and accuracy. Key Advantages High Sensitivity and Accuracy Devices like the SmartKONT contamination monitor are designed to detect minimal levels of radiation, providing precise measurements essential for safety and compliance. Robust and Versatile Design Instruments such as the SmartRAY2 high range dose rate meter feature durable stainless steel housings, enabling reliable performance in various environments, including underwater applications up to 40 meters deep. Comprehensive Monitoring Solutions The Beta-Aerosol monitor offers continuous assessment of beta-emitting aerosols, ensuring real-time detection of airborne radioactive particles, which is crucial for maintaining air quality and safety in controlled environments. Real-Time Monitoring and Fast Response Many of Freiberg Instruments' radiation monitoring systems, such as the GM 2100 Gamma Radiation Monitor, feature real-time detection with visual and audio alarms. This ensures immediate response to radiation hazards, enhancing workplace and environmental safety. RMS series explore more RMS series SmartKONT Learn more RMS series Comet2500 Learn more RMS series SmartRAY2 Learn more RMS series Beta-Aerosol monitor Learn more RMS series GM 2100 Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com Discover More Solutions Crystal Growth and Processing Learn more Photovoltaic Learn more Luminescence Dating and Dosimetry Learn more Research and Development Learn more

Physical Nature of PID-s PID-s is a major threat to c-Si modules, with significant progress made in understanding its mechanisms In the field a large potential between the front glass surface and the solar cells in a module can occur and a shunting of the p-n junction of a Si solar cell and accordingly a decrease in resistance and power output can be caused. The following model was proposed by [1]: The high field strength present in the modules causes a Na+ drift through the SiN x layer. The Na ions diffuse laterally at the SiN x /Si interface (SiO x ) and decorate the stacking faults. The pn-junction is shunted through a hopping process via defect levels of the highly decorated stacking fault (process 1) and additionally the J02 increases due to recombination processes via defect states in the depletion region (process 2). Note that the Na ions are supposed to originate from the Si surface and not the glass. Hence the susceptibility of a module depends mostly on the SiN x layer and the resistivity of the glass and the EVA foil. For more information, please read: [1] V. Naumann et al., The role of stacking faults for the formation of shunts during potential induced degradation (PID) of crystalline Si solar cells, Phys. Stat. Solidi RRL 7, No. 5 (2013) 315-318 Matching Products PID series PIDcon bifacial Quality Control Solution for Bifacial PERC/PERC+, HIT, Topcon, c-Si Solar Cells, Mini Modules, and More Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

Diffusion length Diffusion length The diffusion length is the average distance that the excess carriers can cover before they recombine. Diffusion length depends on the lifetime and mobility of the carriers. \(L = \sqrt{D\tau}\) Note: Diffusion factor (D) is not a constant, but depents on the carrier mobility. \(D = \mu \cfrac{kT}{e}\) For the resolution of every electrical measurement the diffusion length is the limitation. For a measurement of high quality silicon samples a maximal resolution of about 1 mm can be achieved. Matching Products MDP series MDPmap Precision Lifetime Charachterization with Exceptional Sensitivity Learn more MDP series MDPspot Quick and Simple Lifetime Measurement Made Easy Learn more MDP series MDpicts pro High-Resolution, Temperature-Dependent Lifetime Measurement System for Precise Material Characterization Learn more MDP series MDPpro 850+ Advanced Solution for Quality Control of Monocrystalline Silicon Ingots, Bricks, and Wafers Learn more MDP series MDPlinescan Versatile OEM Unit for Lifetime Measurements on Silicon Samples, from Bricks to Processed Wafers Learn more MDP series MDpicts Temperature-Dependent Lifetime Measurement System for Advanced Material Analysis Learn more RES series RESmap High-Precision Resistivity Mapping System for Accurate Material Analysis Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

Static, transient or modulated light excitation pro and con The time-resolved or frequency-modulated, surface photovoltage spectroscopy (SPS) is based on a time-resolved/frequency modulated measurement of the spectral dependence of the surface photovoltage (SPV). It is a powerful non-destructive and contactless characterization method. It is mainly used to study the electronic transitions and optical properties of bulk materials, thin films and heterostructures. High sensitivity and the possibility of room temperature measurements are the key advantages of the SPV method. Another advantage is that there is no need for the preparation of a front contact on the investigated sample. In general, there is no need for preparing the sample for the measurement, allowing to investigate the sample under operation/process conditions in a wide temperature range under different atmospheric conditions. The information depth and thereby the possibility to extract bulk properties is limited by the lights penetration depth and the diffusion length. In comparison to other spectroscopic methods, such as but not limited to optical transmission, deep level transient spectroscopy, photoluminescence or Raman spectroscopy, the time-resolved/frequency modulated SPS or SPV (fixed wavelength) method is fast and uncomplicated and is thus an ideal tool for production floor decisions of sample quality. We distinguish between 3 different excitation modes, but common to all of them is that the relaxation aspect of states in the samples are resolved under ideal conditions. A static SPV measurement is sensitive to any fast or slow process that lead to the separation of photogenerated carriers in space. The sample is illuminated until a saturation of the SPV signal is observed, after which the light is switched of. Measuring 1) the static SPV signal and 2) the time-resolved relaxation time gives a lot of useful information about the state of the material. A SPV measurement that is performed under modulated illumination in a fixed capacitor arrangement is very sensitive to small changes in the SPV signal. And, only those SPV signals, which can follow the modulation frequency are contributing to the measured signal. The response of processes with relaxation times much longer than the modulation period are simply filtered out. The most sensitive SPV measurement that can be made is a transient measurement, where illumination pulse of different pulse width are followed by a time dependent measurement of the decay of the SPV signal – in this way charge separation distances in the nanometre range can be investigated. This is particular important for surface or tunnelling dominated processes in the material. Matching Products SPS/SPV series HR-SPSmap with fixed energy excitation sources High-Resolution and Sensitive Surface Photovoltage Measurement Solutions Learn more SPS/SPV series HR-SPSmap with variable energy excitation source with a variable energy excitation source Learn more DPM series DPM100 Wide range double prism monochromator Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

SPV signal analysis: fits and simulations Charge dynamic simulations in photoactive materials, incl. heterojunction photoactive materials. We are currently developing simulation tools to enable first principle calculations of the electronic structure in a given photoactive material or material combination, based on solid-state physics. The SPS/SPV simulation tool enables users of any SPS/SPV equipment to verify their measurements against simulated scenarios. Thereby for instance reducing development time for new materials research and/or testing the tolerances of a given photoactive material configuration. All transient responses can be fitted between 10 ns and 100 ms using the build-in stretched exponentials multi-parameter fit function with three basic parameters; t I , β i and A i , where t is the transient time constant, β is the stretching factor to the exponential function and A is the signal amplitude. The multi-parameter i can in most cases be limited to 2 (i.e. i = 1,2), 5 is rare, but sometime needed for complex structures. In principle, fitting with i = 1,….,12 is possible. Figure 1 shows an example using SPV for the radial characterization of shallow defects close to the conduction band in a float zone silicon wafer using a fit function consisting of the sum of 5 stretched exponential functions. Matching Products SPS/SPV series HR-SPSmap with fixed energy excitation sources High-Resolution and Sensitive Surface Photovoltage Measurement Solutions Learn more SPS/SPV series HR-SPSmap with variable energy excitation source with a variable energy excitation source Learn more DPM series DPM100 Wide range double prism monochromator Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

SPV-Picts SPV temperature dependence measurements Use this option to make SPV measurements at different temperatures between room temperature and 200°C. Temperature-dependent SPV measurements can be applied to measure activation energies or to investigate temperature dependent reactions/processes in situ. As an example heeling or introduction of defects at surfaces or in the bulk can be investigated in this way. For wide-bandgap semiconductors the onset energy of the SPV signal associated with the bandgap edge is normally not sharp and well defined. By varying the temperature, the onset energy can be measured at different temperatures, resulting in a better estimation of the bandgap edge energies. Some photocatalytic materials have engineered defect states that accelerate the separation of charges. In a high-volume production setup of photocatalytic materials with engineered defect states, the control plan for the activity of the defect states is critical-to-yield. By varying the temperature over a relatively narrow range (say 10°C), the activity can be efficiently tested. Furthermore, the photocatalyst material need to work over broad range of temperatures. This makes the SPV-Picts option almost indispensable for any research programme aiming to develop efficient photocatalytic materials. Matching Products SPS/SPV series HR-SPSmap with fixed energy excitation sources High-Resolution and Sensitive Surface Photovoltage Measurement Solutions Learn more SPS/SPV series HR-SPSmap with variable energy excitation source with a variable energy excitation source Learn more DPM series DPM100 Wide range double prism monochromator Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

Comparison between MPD and SPV techniques MDP (microwave detected photoconductivity): sensitive to moving photogenerated charge carriers (bulk property) SPV (surface photovoltage): sensitive to surface AND bulk properties with respect to ANY photogenerated charge carriers separated in space (moving or trapped) The MDP method does only apply to moderately doped semiconductors or close to perfect optical crystals The SPV method apply to any photoactive materials allowing for charge separation in space (semiconductors, multilayer and multijunction structures, molecular layers, powders) The MDP method can be modelled as a time dependent resistance measurement (DC), t MDP The SPV method can be modelled as a frequency and time dependent capacitance measurement (DC/modulation), t SPV For a non-ideal semiconductor (with defects), there can be a huge difference between the two methods, both methods provide complementary information about bulk and surface properties Matching Products SPS/SPV series HR-SPSmap with fixed energy excitation sources High-Resolution and Sensitive Surface Photovoltage Measurement Solutions Learn more SPS/SPV series HR-SPSmap with variable energy excitation source with a variable energy excitation source Learn more DPM series DPM100 Wide range double prism monochromator Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

Electrical and optical characterization using SPV/Kelvin Photocarrier generation and separation mechanisms Minority carrier lifetime measurement/Diffusion length calculations Trapped carrier dynamics, time resolved Surface Photovoltage measurements Figure 1 shows an example using SPV for the characterization of the polishing process on the double-side polished high-resistivity float zone silicon wafer. The red areas in the plots clearly show that the CMP polishing process is not optimal and even signatures of a handling tool are clearly visible in the plots (left below). Fig. 1: Using SPV for the characterization of the polishing process Matching Products SPS/SPV series HR-SPSmap with fixed energy excitation sources High-Resolution and Sensitive Surface Photovoltage Measurement Solutions Learn more SPS/SPV series HR-SPSmap with variable energy excitation source with a variable energy excitation source Learn more DPM series DPM100 Wide range double prism monochromator Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

Comparison of PID Test Methods A comparison with other widely used methods for PID testing demonstrates that the PIDcon has some unneglectable advantages The PIDcon test has the following advantages compared to other methods: Short duration (usually 4–8h) High variability: test of solar cell, mini-module, glass and EVA Good control of test especially in comparison to corona tests Very low costs per test PIDcon Vs. other test methods Matching Products PID series PIDcon bifacial Quality Control Solution for Bifacial PERC/PERC+, HIT, Topcon, c-Si Solar Cells, Mini Modules, and More Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com

Materials Any photoactive material from raw material to finished device: From powder-based samples over wafers to boules or ingots. From 10 x 10 mm 2 and up to 300 mm diameter From titanium dioxide over silicon and to aluminium nitride (1000+ materials) Matching Products SPS/SPV series HR-SPSmap with fixed energy excitation sources High-Resolution and Sensitive Surface Photovoltage Measurement Solutions Learn more SPS/SPV series HR-SPSmap with variable energy excitation source with a variable energy excitation source Learn more DPM series DPM100 Wide range double prism monochromator Learn more Get in touch Do not hesitate to contact us – we are available to assist you with any inquiries or requests. Use our inquiry tool or reach out via email: sales @ freiberginstruments.com