CEL-QPCE2010 Solar Silicon Battery Spectral Response System Introduction: The radiant energy of the light source at different wavelengths is different, and the responsiveness of the detector at different wavelengths is also different. Therefore, the measured response current will also be greatly different. Assuming that the system noise N is constant and the response current S is large, the system signal-to-noise ratio (S/N) is large and does not affect the measurement accuracy. If the response current is small, even less than the system noise, S/N<1, at this time. The accuracy of the measurement is greatly affected. In order to solve this problem, the system adopts the correlation detection method, and uses the correlation of the signal in time to extract the periodic signal buried deep in the noise. The specific method is: the light source is modulated by a chopper into a periodic signal having a fixed frequency (reference frequency), and the detector also outputs an electrical signal having the same frequency, and the electrical signal containing the reference frequency is detected by the lock-in amplifier, and Signals (noise) at other frequencies are suppressed, which improves the signal-to-noise ratio of the system and ensures measurement accuracy. Applications: Applicable battery: single crystal silicon, polycrystalline silicon solar cell; material performance analysis under AC analysis mode Test items: absolute spectral response, external quantum efficiency, spectral transmittance, spectral reflectance (optional), internal quantum efficiency (optional), short-circuit current density under standard solar AM1.5G illumination, surface uniformity, etc. 1) External quantum efficiency test: Using the measurement of the spectral response of the solar cell, the quantum efficiency η(λ) of the solar cell can be obtained. 2) Spectral reflectance test: input the monochromatic light output from the monochromator into the integrating sphere, respectively put the standard whiteboard with the known spectral diffuse reflectance and the measured solar cell into one opening of the integrating sphere, and measure the integrating sphere another The output spectral current of the detector at the opening is obtained by comparison to obtain an absolute spectral reflectance curve. 3) Spectral transmittance test: The spectral current/voltage value of the standard detector when the sample is placed in the sample chamber and the sample is not placed, and the spectral transmittance of the solar cell can be measured compared to the transmittance of the sample. Can measure the spectral transmittance of glass 4) Internal quantum efficiency test: The internal quantum efficiency is obtained in part by subtracting the influence of the reflectance on the external quantum efficiency. Technical Parameters: Applicable batteries: monocrystalline silicon, polycrystalline silicon, semiconductor materials Control mode: software control, automatic scanning, automatic elimination of errors, automatic deduction of background Spectral range: 200-1100nm Scanning interval: ≥1nm continuously adjustable Spectral scanning: fully automatic, continuous Test result repeatability: <0.3% (short circuit current) Working mode: AC mode AC, Chopping frequency: 5-1000Hz Temperature control station: Temperature control range 5-40 ° C (± 0.5 ° C), optional Bias light source: optional 2 way Monochromator: focal length 300mm, 150mm optional
Introduction: The radiant energy of the light source at different wavelengths is different, and the responsiveness of the detector at different wavelengths is also different. Therefore, the measured response current will also be greatly different. Assuming that the system noise N is constant and the response current S is large, the system signal-to-noise ratio (S/N) is large and does not affect the measurement accuracy. If the response current is small, even less than the system noise, S/N<1, at this time. The accuracy of the measurement is greatly affected. In order to solve this problem, the system adopts the correlation detection method, and uses the correlation of the signal in time to extract the periodic signal buried deep in the noise. The specific method is: the light source is modulated by a chopper into a periodic signal having a fixed frequency (reference frequency), and the detector also outputs an electrical signal having the same frequency, and the electrical signal containing the reference frequency is detected by the lock-in amplifier, and Signals (noise) at other frequencies are suppressed, which improves the signal-to-noise ratio of the system and ensures measurement accuracy.
