FOUR-POINT PROBE
The Ossila Four-Point Probe is an easy-to-use tool for the rapid measurement of sheet resistance of thin films. Sheet resistance (also known as surface resistance or surface resistivity) is a common electrical property used to characterize thin films of conducting and semiconducting materials. It is a measure of the lateral resistance through a thin square of material, i.e. the resistance between opposite sides of a square. The key advantage of sheet resistance over other resistance measurements is that it is independent of the size of the square, enabling easy comparisons between different samples.
Specification
Electrical Specifications:
Voltage Range ±100 μV to ±10 V
Current Range ±1 μA to ±200 mA (5 ranges)
Sheet Resistance Range 100 mΩ/□ to 10 MΩ/□ (ohms per square)
| Sheet Resistance | Accuracy* | Precision** | Measured at Range |
| 100 mΩ/□ | ±8% | ±3% | 200 mA |
| 1 Ω/□ | ±2% | ±0.5% | 200 mA |
| 10 Ω/□ | ±1% | ±0.5% | 200 mA |
| 100 Ω/□ | ±1% | ±0.05% | 20 mA |
| 1 kΩ/□ | ±1% | ±0.03% | 20 mA |
| 10 kΩ/□ | ±1% | ±0.02% | 2000 µA |
| 100 kΩ/□ | ±2% | ±0.05% | 200 µA |
| 1 MΩ/□ | ±8% | ±0.5% | 20 µA |
| 10 MΩ/□ | ±30% | ±5% | 20 µA |
Physical Specifications:
| Probe Spacing | 1.27 mm (0.05") |
| Rectangular Sample Size Range | Long Edge Minimum: 5 mm (0.20") Short Edge Maximum: 152.4 mm (6") |
| Circular Sample Size Range (Diameter) | 5 mm to 152.4 mm (0.20" to 6.00") |
| Maximum Sample Thickness | 8 mm (0.31") |
| Overall Dimensions (W x H x D) | 145 mm x 150 mm x 240 mm (5.71" x 5.91" x 9.45") |