Keysight Graphical Picoammeter/Electrometer
World's Only Unit that can Confidently Measure Down to 0.01 fA and Up to 10Ω

September 2, 2014

1. Introduction
2. Confidently Measure Down to 0.01 fA and up to 10 PΩ
3. Capturing Transient Signal Effects and Selecting Desired Measurements
4. Instant Statistical Analysis of Measurement Data
5. Eliminating AC Power Line Noise from Measurement
6. Ensuring Maximum Measurement Accuracy
7. Summary
8. Related Information

Research and development into new substances such as nanomaterials, graphene, polymers, and dielectric materials has increased significantly in recent years. One key challenge facing this rapidly growing market is that these new materials require extremely sensitive electronic measurements (e.g., ultra-low current measurements below the pA level and high-resistance measurements beyond the GΩ range) that conventional Digital Multimeters (DMMs) cannot handle. Instead, high performance picoammeters and electrometers are commonly used to make these types of sensitive measurements. However, conventional picoammeters and electrometers only provide a numeric display and do not support any graphical capabilities to help improve measurement confidence.

The Keysight B2980A Series of femto/picoammeters and electrometers/high resistance meters now offers engineers and researchers performing sensitive measurements on new materials a better alternative (Figures 1 and 2). These instruments not only provide an industry-best 0.01 fA current measurement resolution, but they also have the world’s only graphical display that provides innovative capabilities designed to maximize measurement confidence. .

The B2980A Series of femto/picoammeters and electrometers feature a 2 pA to 20 mA operating range and an internal 1000 V source designed to enable accurate measurement down to 0.01 fA (10-17A) and up to 10 PΩ (1016 Ohm). The best-in-class 2-pA range with 0.01 fA resolution help users make the super sensitive measurements required for the research and development of new materials.

The Keysight B2980A Series is available in four versions, allowing users to purchase an instrument with the exact amount of testing capability they need (see the Table).

B2980A Series Specifications
Model		Femto/Picoammeter		Electrometer/ High Resistance Meter
		B2981A	B2983A	B2985A	B2987A
Measurement resolution		6½ digits	6½ digits	6½ digits	6½ digits
Current measurement		0.01 fA to 20 mA	0.01 fA to 20 mA	0.01 fA to 20 mA	0.01 fA to 20 mA
	Minimum range	2 pA	2 pA	2 pA	2 pA
Maximum measurable Resistance				Up to 10 PΩ	Up to 10 PΩ
Voltage measurement				1 μV to 20 V	1 μV to 20 V
	Input resistance			> 200 TΩ	> 200 TΩ
Charge measurement				1 fC to 2 μC	1 fC to 2 μC
Temperature measurement				✔	✔
Humidity measurement				✔	✔
Voltage source				Up to ±1,000 V	Up to ±1,000 V
	Minimum resolution			700 μV	700 μV
Reading rate		20,000 rdg/s	20,000 rdg/s	20,000 rdg/s	20,000 rdg/s
Battery operation			✔		✔
Other key features		Graphical capability (Meter View, Graph View, Histogram View, Roll View), Auto navigation, 100 k points sample buffer,  Interface (USB, LAN, GPIB, LXI Core), Free PC control software, etc.

A significant challenge with conventional picoammeters/electrometers is that they only have numeric displays (Figure 3). This presents a problem for engineers and researchers since it does not give them any control over when to take data during a transient response.

With the B2980A Series’ time-domain view (Roll View), users can visually choose when to capture data (Figure 4). Up to 100,000 of these data points can be stored for later retrieval. With a sampling rate of up to 100 kHz, the time-domain view can reveal real-time measurement trends and provides valuable insight into the dynamics of the Device’s-Under-Test (DUT’s) behavior.

To facilitate data analysis, the B2980A Series features flexible graphing capabilities. In Graph View, the electrometers can plot I-V curves on their displays using values from either the internal voltage source or voltage measurement data. A variety of other X-Y plots such as I-t, V-t, R-t, Q-t, and I-R can also be easily generated; although the specific graphical display capabilities available will depend on the product model being used. These powerful and versatile graphical capabilities allow users to gain valuable insight when making sensitive measurements.

A real-time histogram view provides quick statistical analysis of measurement data. Previously, with conventional picoammeters/electrometers the only way to generate histogram plots was using an external PC, and it could often take a lot of time to transfer and process the data. Since histogram data can often reveal instabilities or fluctuations in measurement data, being able to view this information in real-time is extremely important. The B2980A Series’ histogram display overcomes these challenges (see Figure 5). The display is continuously updated on a real-time basis, which allows users to instantly debug their measurement setup environment.

AC power line noise strongly impacts sensitive measurements. To overcome this challenge, the B2980A Series features two battery operated models that enable users to make power-line-noise-free measurements (Figure 6). This allows the B2980A Series to detect low-level signals that conventional instruments are unable to detect.

When performing sensitive measurements, making appropriate cabling connections is often one of the more difficult challenges. Many factors can contribute to measurement noise or instability, including incorrect cabling, poor cable quality and improper guarding. However, determining the root cause of a measurement fixturing issue from among these factors is not easy. Conventional instruments do not help users solve these types of issues and they typically only offer written guidance on best practices. In contrast, the B2980A Series features a Setup Integrity Checker function that isolates the cause of noise related to setup elements, including such things as: cables, adapters, shields, and chambers, and displays the information in tabular format on the front-panel interface.

As shown in Figure 7, the Setup Integrity Checker function allows users to compare the noise level of the instrument with no cables connected against the noise level with different setup elements connected. By comparing the noise levels (as standard deviation) of different setup elements side-by-side, it is easy to determine the quality of cables and other setup elements necessary for any given measurement. As an added benefit, the B2980A Series has specialized accessories available to facilitate certain types of measurements.

The Keysight B2980A Series of femto/picoammeters and electrometers/high resistance meters offers best-in-class measurement performance to meet the current and future requirements necessary to execute highly sensitive measurements. In addition, numerous innovative features help maximize measurement confidence.

Keysight is a global electronic measurement technology and market leader helping to transform its customers’ measurement experience through innovation in wireless, modular, and software solutions. Keysight provides electronic measurement instruments and systems and related software, software design tools and services used in the design, development, manufacture, installation, deployment and operation of electronic equipment. Information about Keysight is available at www.keysight.com.