SPS

SPVSurface Photovoltage Spectroscopy Measurement System

Surface photovoltage spectroscopy (SPV) is an important research tool in semiconductors and many modern high-tech fields. A surface potential barrier is generated at the contact between semiconductor and metal. When light is irradiated on the contact interface between the sample and metal, a potential difference is established between the illuminated and non illuminated surfaces. The relationship between this potential difference and the wavelength of the incident light is recorded to obtain the surface photovoltage spectrum. The surface photovoltage spectrum reflects the light absorption properties of materials and the band band transitions of electrons, while also being influenced by the lifetime of photogenerated carriers. SPV is commonly used to measure the lifetime of non-equilibrium minority carriers, and the steady-state measurement method is commonly employed. It uses stable lighting to stabilize the distribution of non-equilibrium minority carriers in semiconductors, thereby accurately and quickly estimating the lifespan of spoons.

Surface photovoltage (SPV) spectroscopy is one of the sensitive methods for studying the surface properties of solids (approximately 108 q/cm2, with q as the unit charge). Its sensitivity is several orders of magnitude higher than XPS and Auger electron spectroscopy, with simple operation, good reproducibility, and no damage to the sample or change in its morphology during testing.

A key measurement uncertainty factor in surface photovoltage spectroscopy measurement is the stability of the light source. Therefore, our company specially provides a high stability 500W xenon lamp as the light source, which greatly improves the accuracy of the measurement.

The series surface photovoltage measurement system mainly consists of xenon lamp light source, automatic scanning monochromator, fiber bundle, lock-in amplifier, optical chopper, darkroom, and data acquisition software.

Main technical parameters:

◆ Light source type: Xenon lamp

◆ Light source power: 500W

◆ Light source stability: better than 1% (can reach 0.5%)

◆ Monochromator focal length:300mm (type),500mm focal length (type)

Monochromator relative aperture: f/3.9 (type), f/6.5 (type)

Monochromator output bandwidth: 0.1-16nm (type), 0.05-8nm (type)

Spectral coverage range: 200-1100nm (optimal spectral range: 330-1000nm)

Monochromator data interface: USB 2.0

◆ Lock in amplifier brand and model: SR510 model from SRS company in the United States

◆ Chopper brand and model: SR540 model from SRS company in the United States

◆ Type of optical outlet: Fiber optic output

Fiber bundle length: 1

Fiber bundle diameter:1mm

The dark box can be operated horizontally or vertically, making it convenient to place different types of solids, powders, or solutions

The data acquisition software can directly control the monochromator to collect wavelength and surface photovoltage signals,

Optional models:

Specification Description

500W xenon lamp,300mm focal length monochromator, fiber bundle output to dark box, SR510+SR540, software

500W xenon lamp,500mm focal length monochromator, fiber bundle output to dark box, SR510+SR540, software

[Note] The configuration of monochromator and lock-in amplifier can be selected according to customer needs, but the random software is not suitable for all brands of lock-in amplifiers. Please consult the company's sales department for details.