The Electrochemical Kelvin Probe measures CPD (Contact Potential Difference) value and evaluates Work Function of  electrochemical samples in contact with electrolyte.

Measurements of work function is particularly useful in semiconductor physics because they provide a position of Fermi level in examined material.

The Electrochemical Kelvin Probe, when coupled with a light source, measures Surface Photovoltage (SPV) of a sample when dry or wet interface is illuminated.

Electrochemical Kelvin Probe comes with a dedicated electro-chemical cuvette. There, a sample is floating on an electrolyte. The Kelvin probe tip approaches the exposed top side of the sample. This way, there is no electrolyte layer of top of the sample that can affect the measured CPD. Still, the bottom side of the sample remains in contact with an electrolyte.

Light can illuminate either top surface of the sample or bottom sample-electrolyte interface.

A possible chemical reaction on the sample-electrolyte interface will affect the measure value of CPD. Also a choice of Reference Electrode (RE) selected for the measurement will offset the CPD.

Optionally, the Electrochemical Kelvin Probe may be equipped with the inert gas flow system to provide neutral environment inside the Faraday’s cage.

The Electrochemical Kelvin Probe set consists of:

• Controller unit,
• Kelvin Probe instrument with the Probe Tip,
• Electrochemical cuvette,
• Faraday Cage.

The Electrochemical Kelvin Probe instrument is equipped with:

• Protective bay to park the Probe Tip after experiment,
• Laser pointer to indicate the area directly,
• Light source that helps to handle the sample when the instrument is covered with the Faraday Cage,
• Laser barrier to precisely detect the Probe Tip distance to the sample,
• Golden Probe Tip,
• Sample holder for the Electrochemical cuvette,
• Electrochemical cuvette with the sample placed on top.

Probe Tip

The most important part of the Kelvin Probe instrument is the Probe Tip. The probe is fully designed and manufactured by Instytut Fotonowy. The reference electrode is made of Au mesh of 2.5 mm diameter. It provides high signal to noise ratio, even from a distance of 0.5 mm above the sample. Thus, it does not matter if the examined sample surface is rough or polished. The tip oscillations are generated with an electromagnet.

Sample illumination

Although you may use any light source at your disposal to provide sample illumination, it is convenient to opt for our LED Revolver or Xenon Lamp with a Monochromator because FotoGUI software handles them already and carries out automatic experiments with LED switching or wavelength scans.

• Light delivery from the top

Faraday Cage

A Faraday Cage covers the entire instrument, shielding the setup from the ambient light and electromagnetic fields.

Gas-tight Faraday Cage with inert gas flow system

Since measurement of the CPD is often sensitive to environmental factors like temperature, humidity, dust and chemical contaminants, Kelvin Probe may be placed inside the hermetic version of the Faraday Cage filled with the inert gas.

Laser barrier

The Kelvin Probe is equipped with the Laser barrier system. It automatically detects the sample top edge. Each time the probe approaches the sample being examined, an accurate distance between the sample surface and the Probe Tip is measured with 20 µm precision.

General:

• Weight: 15 kg,
• Size: 40x40x45 cm,
• PC connectivity: USB 2.0,
• Power supply: 230 V, 50 Hz or 115 V, 60 Hz,
• Measurement technique: 2-channel lock-in-amplifier,
• Laser barrier to automatically detect the substrate and prevent the tip from running into the sample,
• Auxiliary sensors: humidity, temperature,
• Small lamp,
• Laser pointer for examined point of the surface indication,
• Sample holders:
  – Freely shaped solid state with top contact holder,
  – Bottom contact holder,
  – Electrochemical holder,

Faraday Cage:

• Standard / gas-tight with inert gas flow system,

Measurement unit:

• Bias voltage range: -5 ÷ 5 V,
• Voltage measurement resolution: 0.15 mV,
• Current ranges: 300 nA, 30 nA, 3 nA, 300 pA,

电化学开尔文探针可以测量接触电位差（CPD）值，并评估需要电解质提供电接触的电化学样品的功函数。这种测量不仅可以在样品表面的单个点上进行，而且可以扫描整个样品表面。

功函数的测量在半导体物理学中特别有用，因为它提供了被检查材料费米能级的位置。

配备光源的开尔文探针使得可以检查样品的电子表面态。电子表面态在电荷转移中起着重要作用，这对于光伏材料和光电化学尤为重要。

电化学开尔文探针是一种创新的设置，配备专用的电化学比色皿。通过提供新型的比色皿，该设置使得被检测表面既与电解质接触，又位于比色皿顶部，从而在满足探针主要与样品表面相互作用的要求下进行CPD测量。同时，样品仍然与电解质接触。

开尔文探针可以配备光源，从而可以检查样品的电子表面态。

将光传送到样品可采用两种方式：从上方照明样品表面，或从下方照射样品-电解质界面。
通过比较干燥样品和与电解质接触的样品的CPD，可以探索可能发生的化学反应维持的电化学电池电压，这种反应发生在样品和参考电极之间。

可选地，电化学开尔文探针可以配备惰性气体流系统，以在法拉第笼内提供中性环境。

电化学开尔文探针套装包括：

• 控制器单元，
• 带有探针尖的开尔文探针仪器，
• 电化学试样池，
• 法拉第笼。

电化学开尔文探针仪器配备有：

• 保护隔间，用于实验后停放探针尖，
• 激光指示器，可直接指示区域，
• 光源，在仪器覆盖着法拉第笼时有助于处理样品，
• 激光障碍物，精确检测探针尖到样品的距离，
• 金色探针尖，
• 用于电化学槽的样品支架，
• 放置在顶部的电化学槽中的样品。

探针尖

开尔文探针仪器最重要的部分是探针头。探针完全由Instytut Fotonowy设计和制造。参考电极由直径为2.5毫米的金网制成。它提供了高信噪比，即使在距离样品表面0.5毫米的位置也是如此。因此，无论被检查的样品表面是粗糙还是光滑都无关紧要。探针尖的振动是由电磁铁产生的。

样品照明

样品可以在测量过程中通过光纤进行照明。光纤输入处的光可以由LED旋转器、与单色仪结合的氙灯或任何其他所需类型的光源提供。

• 从顶部进行光传递

法拉第笼

整个仪器被法拉第笼覆盖，以屏蔽来自环境光和电磁场的干扰。

带有惰性气体流系统的气密法拉第笼

由于CPD的科学测量通常对温度、湿度、灰尘和化学污染物等环境因素敏感，Kelvin探针可以放置在带有惰性气体流系统的气密法拉第笼内部。

激光屏障

凯文探针配备了激光屏障系统。该系统会自动检测待检样品的衬底。每当探针接近被检样品时，系统会以20微米的精度测量样品表面与探针尖端之间的准确距离。

总体:

• 重量：15公斤，
• 尺寸：40x40x45厘米，
•  PC连接：USB 2.0，
•  电源：230V，50Hz 或 115V，60Hz，
•  测量技术：2通道锁定放大器，
• 激光屏障，可自动检测衬底并防止尖端碰撞样品，
• 辅助传感器：湿度，温度，
•  小灯，
• 激光指示器，用于指示表面检测点，
•  样品夹具：
  – 自由形状固态顶部接触夹具，
  – 底部接触夹具，
  – 电化学夹具，

法拉第笼：

• 标准/气密型，配备惰性气体流系统，

测量单位：

• 偏压范围：-5÷5 V，
• 电压测量分辨率：0.15 mV，
• 电流范围：300 nA、30 nA、3 nA、300 pA、