Scientific grade Kelvin probe

Scientific grade Kelvin probe：

The characteristics of many materials are determined by their surface. One of the most important surface properties is the work function.

Scientific grade Kelvin probeIt can accurately measure the work function of different semiconductors and conductive materials with high precision and accuracy.

Non contact measurement involves oscillating capacitance, where one electrode is the sample and the other electrode is the gold gate oscillating reference electrode. Therefore, the measured value refers to the work function of gold (5.1 eV). The measurement resolution can reach 0.1 meV, and the integration time is long enough. Kelvin probes can be used for various types of surface studies, including corrosion, adsorption/desorption, surface charging, catalytic activity, etc.

For ease of use, the probe is equipped with a laser pen and a digital microscope. The electric vertical positioning system allows for the reproduction of reference electrodes at the same distance from the specimen surface (with an accuracy of 10 μ m). X-Y positioning can be installed as an option. The system is also equipped with broadband optical guides, which can be used in conjunction with CNC monochromators and high-pressure xenon arc lamps. The wavelength range from 300 to 1000 nm can be used for continuous or pulsed sample illumination.

This configuration allows for the measurement of surface functionality and charge, surface photovoltage spectroscopy, and other photophysical techniques, with a photovoltage resolution of better than 5 mV (0.1 mV when applied for longer integration times). The entire system adopts a grounded Faraday cage to reduce the impact of electrical noise and stray light. This surface photovoltage spectrometer is a necessary tool for studying photocatalysts, organic and inorganic semiconductors, solar cells, and other photoactive materials and devices.

With the help of this Kelvin probe/surface photovoltage spectrometer, real-time monitoring of semiconductor photocorrosion, photodesorption, and photocatalytic reactions has also become possible.

Design

The device consists of a swinging gold probe installed on a fixed bracket, a z-axis electric worktable, an electronic control unit, and a Faraday cage.

The sample is placed on a manual or electric XY table with a movement range of 1.5 cm in any direction.

The probe is connected to a z-level and can be placed at the desired distance from the sample.

A red laser indicator displays the location where the probe oscillates during the measurement process.

When the system is covered by a Faraday cage, the USB microscope and white LED can play a good role at this time.

Light is transmitted into the sample through liquid waveguides or optical fibers, thus eliminating the electromagnetic interference that may be generated by the light source.

During idle operation or storage, fragile gold probes are placed in a protected space to prevent accidental damage.

The system is also equipped with an automatic sample height sensor.

probeIt is from our companyComponents designed and manufactured. It provides:

Even at a distance of 0.5 mm above the sample, there can be a significant signal, so whether the sample surface is rough or polished is not important.

Transparency that allows light to pass through. Through this method, the sample can be illuminated by a vertical beam of light.

The oscillation is generated by an electromagnet.

The entire detector is covered with a Faraday cage, making it unaffected by the external environment.

Specifications