The Quantum Efficiency Measurement Station is a complete experimental setup for solar cells spectral response investigation. The sample is illuminated with a monochromatic beam produced by the Monochromator with two types of light sources at the entrance: Xenon Lamp and Halogen Lamp. Both lamps provides wavelengths range that covers UV, VIS and IR light. Instrument with the BIAS Light extension enables to excite the sample with a normalized white AM1.5G light from an additional Xenon Lamp combined with the Air Mass Filter. The examined cell is placed on a motorized vacuum XY Table, with a manual Z shift. Measurements are performed in a chamber that screens the setup from ambient light and external EM fields. The incident light intensity, is monitored with a Dual Band Si/InGaAs Photodiode. All the system components are fully automated, controlled via software.

Quantities measured by the instrument:

• I-V characteristics,
• Open Circuit Potential (OCP) under illumination,
• Spectral reflection coefficient (R),
• Spectral transmission coefficient (T),

Characteristics:

• External quantum efficiency (EQE or IPCE),
• Internal quantum efficiency (IQE or APCE),
• Short-circuit current density (Jsc),
• Fill Factor.

The system consists of:

1. Sample Chamber,
2. Motorized Multi-Axis Vacuum Table with a built-in photodiode,
3. Integrating Sphere,
4. Monochromator with two entrance slits for automatic switching between light sources,
5. Xenon Lamp at the first entrance of the Monochomator,
6. Halogen Lamp at  the second entrance of the Monochromator,
7. Lockin for measured signals processing,
8. Xenon Lamp + AM1.5G Filter (BIAS Light extension)

Sample Chamber interior

General

• Total wavelengths range: 200 ÷ 1650 nm,
• Adjustable white light beam intensity on the sample: 0.01 ÷ 0.1 W/cm²,
• Illumination homogeneity: 10%,

Xenon Lamp

• 150 W xenon burner,
• Water cooling system,
• Low EM emission igniter,
• Stabilization modes:
  – electric current stabilization (distortions < 1%),
  – electric power stabilization,
  – light intensity stabilization (unique solution to provide constant sample illumination during the experiment),
• Maximum radiation intensity on the sample: 35 mW/cm²

Halogen Lamp

• Electrical power of halogen bulb: 150 W,
• Reflector type: elliptic,
• Air cooling system,

Monochromator

• Three gratings on the turret, each optimized for different wavelengths range,
• Automated grating switching depending on the wavelength selection,
• Motorized output and input slits, controlled via software,
• Two input slits for different light sources, switched via software,
• Entrance and output slit opening range: 0 ÷ 5 mm,
• Motorized internal shutter, that provides full cut off of the light beam,
• Maximal spectral resolution: 0.1 nm (depends on the input and output slits width),
• Chopper at the output,