The QE-PV-SI QE/IPCE measurement kit allows researchers to measure Quantum efficiency (QE) and Incident Photon to Charge Carrier Efficiency (IPCE) measurement for solar cells, detectors, or any other photon-to-charge converting device. We selected the most suitable components for your measurements needs. All Oriel® components are from Newport Corporation, an industry leader in light sources and spectroscopy products, as well as continuous wave solar simulators.
What are QE and IPCE?
Quantum efficiency (QE) and Incident Photon to Charge Carrier Efficiency (IPCE) indicates the ratio of the number of photons incident on a solar cell to the number of generated charge carriers. Quantum efficiency is a measure of external efficiency.
The QE/IPCE measurements is critical especially during the materials research and cell design stage to understand the conversion efficiency as a function of the wavelength of light impingent on the cell. In this way, the composition and topography can be modified to optimize conversion over the broadest possible range of wavelengths. The system is built by an industry leader in light sources and spectroscopy, so you can rely on our expertise to ensure accuracy of the measurement.
Figure 1. External QE measurement obtained on a mono-Si solar cell.
How to Measure QE and IPCE?
The key to accurately measure the QE/IPCE of a solar cell is to quantify the intensity of monochromatic light incident to the device under test and how much current is generated. We can provide the light sources, monochromators and related accessories, which are the most common building blocks of a QE/IPCE system that will allow you to quickly set up the experiment, or we can provide our QE-PV-SI factory assembled kit that has been tested against a reference to insure performance.
Components
The QE-PV-SI kit combines all the components necessary to build a free space QE measurement setup to measure the external QE measurements including:
- Light source(s) – Uses a 300 W Xe Arc Research Source see 200 - 500 W Hg Research Arc Sources. The light source is coupled to a monochromator to create the scanning light.
- CS260 Monochromator – The monochromator provides excellent throughput and resolution, and is controlled via USB connection through our 77890 Tracq Basic software.
- Merlin lock-in amplifiers, optical chopper and Si detector – A dual channel Merlin lock-in amplifier is utilized for the sensitive optical power and current measurements. The Merlin lock-in amplifier comes with a built-in chopper controller. An optical chopper with one two-aperture blade is also included in the kit.
- Optics and opto-mechanical components – Basic focusing optics and opto-mechanical components are provided for your convenience so that the output spot size can be controlled. Depending on the desired spot size other combinations of optics can be used for the incident beam on the cell under test.
- Current Preamp – We included an Oriel® Preamp and a cable specifically designed to interface a current generating device to work with the Merlin Digital Lock-in Amplifier. All you need to prepare is a connection from your test cell to the BNC input of the preamp. The 70710QE is not suitable when white light bias is required as the white light may saturate the signal. A 70714 Light Bias preamp is also available which can handle light bias with white light or colored light.
- Start-up Instruction – This detailed start-up instruction includes background information and step-by-step instruction on how to construct a QE measurement setup, using the provided components.
- Automated filter wheel and order sorting filters – An automated filter wheel, which is easily configured in the QE software for a computer control, and suitable order sorting filters are included in the kit.
Solar Cell Fixture Available
A basic solar cell and detector mounting configuration is available with the kit and a customized configuration can be specified using Newport components. The output beam propagates in the horizontal direction and the user must provide his or her fixture for the test solar cell. For beam routing, we supply a minimal set of lenses and optomechanical components.
Software
The QE software is constructed within the familiar 77890 Oriel® Tracq Basic V6.0 software. The software controls all the components, including the monochromator, the order sorting filter wheel, the Merlin lock-in amplifier and the chopper. One can also perform the data collection measurements in separate scans and save the data for post processing or the software can calculate and display a QE curve.
Figure 2: Simple scans can be taken and saved for external processing or a simple QE scan can be run directly within TracqBasic 5.0 or above.
