How to make a sweep measurement with 2 channel sources

Agilent B2902/12A Precision Source/Measure Unit
How to make a sweep measurement with 2 channel sources
This material shows how to perform a sweep measurement with 2 channel sources through an example of IdVg
characterization of FET. Figure 1 illustrates the connection and condition supposed in the example of measuring FET using
a member of the B2902A or B2912A.
Ch1
A
High Force
Gate
-
V
Ch2
-
Drain
V
-
Source
A
-
Low Force
DUT : FET
Ch1
Source Mode
Start Value
Stop Value
Points
Current Limit
: Gate
: Voltage
:0V
:2V
: 101
: 1 uA
Ch2
Source Mode
Start Value
Stop Value
Points
Current Limit
: Drain
: Voltage
:2V
:2V
: 101
: 100 mA
Figure 1. Connection and condition supposed in the example
Figure 2 shows the timing chart for the sweep measurement using 2 channel sources with the front panel operation. The
specified source values are sourced immediately after turning on each
. Then, when you press
, the
instrument will make a sweep measurement. If it is necessary, you can specify any measurement trigger delay time which
is the wait time after sourcing each source value and before making a measurement. The measurement time consists of
Measurement Speed and some overhead time. Measurement Speed is the parameter specified by the user. Overhead
time includes the time to change the measurement range, etc.
Ch 2 V or I
Output ON
:Measurement
Source Value
Start/Stop Value
Output Off State
TMD
TM
TMD
TM
TMD
TM
Time
TMD
Ch 1 V or I
Stop Value
Source Value
TMD
TMD
TM
TM
TM
Start Value
Output Off State
Output ON Press Trigger
TMD : Measurement Trigger Delay Time
Internal Trigger
Time
TM : Measurement Time
Figure 2. Timing chart for the sweep measurement using 2 channel sources
Agilent B2902/12A Precision Source/Measure Unit
Performing a sweep measurement with 2 channel sources
1.
Setting up Channel 1
Step 1.
Press
Step 2.
Press
repeatedly until Single View for Channel 1 is shown in the display.
to edit the channel 1 source function, and then select
(1) Press Mode
Step 3.
Press
Press
(2) Enter Source Value
to edit the channel 1 limit value, and then enter 1 uA to set it to 1 uA.
(1) Press Limit
Step 5. Press
current.
(2) Press VOLTS (V)
to edit the channel 1 source value, and then enter 0 V to set it to 0 V.
(1) Press Source
Step 4.
to set it to the voltage source.
(2) Enter Limit Value
to configure the channel 1 measurement parameter, and then select
(1) Press Measure
(2) Press AMPS (I)
to set it to the
Agilent B2902/12A Precision Source/Measure Unit
Step 6. Press
Sub-Panel.
to change the keys shown in Assist keys, and then press
(1) Press Show Sweep
Step 7.
Press
, then press
(2) Sweep Sub-Panel appears
to turn on Single Linear Sweep Mode. After turning on Single Linear
Sweep Mode, you can see Source Shape which shows the single linear sweep mode.
(1) Press LINEAR SINGLE
Step 8.
Rotate
to show Sweep
Source Shape
to select Channel 1 Sweep Parameters and set them up as below.
(Start: 0 V, Stop: 2 V, Points: 101, Step: 20 mV)
Agilent B2902/12A Precision Source/Measure Unit
2.
Setting up Channel 2
Step 1.
Press
Step 2.
Press
to show Single View for Channel 2.
to edit the channel 2 source function, and then select
(1) Press Mode
Step 3.
Press
Press
(2) Enter Source Value
to edit the channel 2 limit value, and then enter 100 mA to set it to 100 mA.
(1) Press Limit
Step 5. Press
current.
(2) Press VOLTS (V)
to edit the channel 2 source value, and then enter 0 V to set it to 0 V.
(1) Press Source
Step 4.
to set it to the voltage source.
(2) Enter Limit Value
to configure the channel 2 measurement parameter, and then select
(1) Press Measure
(2) Press AMPS (I)
to set it to the
Agilent B2902/12A Precision Source/Measure Unit
Step 6.
Rotate and press
to edit the channel 2 sweep parameters. Then press
Linear Sweep Mode.
(1) Rotate and press
to edit
Channel 2 Sweep Parameters
Step 7.
Rotate
(2) Press LINEAR SINGLE
to select Channel 2 Sweep Parameters and set them up as below.
(Start: 2 V, Stop: 2 V, Points: 101, Step: 0 mV)
3.
Setting up Graph View
Step 1.
Press
to show Graph View
Step 2.
Rotate and press
(1) Rotate
Type field
to edit the X-axis data type
to select X-axis Data
(2) Press
Type
to edit X-axis Data
to turn on Single
Agilent B2902/12A Precision Source/Measure Unit
Step 3.
Press
, and then select
to set the X-axis data type to the channel 1 voltage.
(1) Press More …
4.
(2) Press Ch 1 V (V1)
Performing measurement
Step 1. Press
measurement.
for both channels to source the voltage, and then press
(The status information will show
to perform a
during the measurement.)
Step 2. Press
to adjust the scale of the graph after finishing the measurement. Now you can see the
measurement result on the GUI of the B2902/12A as bellow.
Step 3.
If you’d like to change the graph scaling of Y-axis from LINEAR to LOG, rotate and press
Y-axis scaling.
(1) Rotate and press
Y-axis scaling
to select
(2) Press LOG
to select
Agilent B2902/12A Precision Source/Measure Unit
Step 4.
If you’d like to change the graph scale value of Y-axis, rotate and press
(1) Rotate and press
Y-axis scale value
to select
to modify Y-axis scale value.
(2) Enter the scale such as 10 pA
Configuring the measurement speed
In the default setting, the instrument selects the appropriate measurement speed and range automatically to get the fine
accuracy. However, you can also specify these parameters on the GUI of the B2902/12A to meet a variety of the
requirement to the measurement conditions.
For example, let’s try to change the measurement speed to NORMAL to make a measurement more carefully. If you select
NORMAL, the aperture time is set to 1 PLC. Here, PLC stands for power line cycle and the specified number of power line
cycles is used per a measurement.
Step 1.
Press
Step 2.
Press
repeatedly until Single View for Channel 2 is shown in the display.
to edit the channel 2 measurement speed, and then select
(If you can’t see
in Assist keys, press
(1) Press Speed
to set it to NORMAL.
to change the keys shown in Assist keys.)
(2) Press NORMAL
Agilent B2902/12A Precision Source/Measure Unit
Configuring the measurement range operation
The parameters which configure the measurement range operation can be displayed in Range Sub-panel in Single View,
although Sweep Sub-Panel is shown at this moment. In the default setting, the B2902/12A performs the current
measurement using 1 uA current minimum measurement range with AUTO range operation. With AUTO range operation,
the B2902/12A selects the proper range for the measurement with specified minimum measurement range so that you
don’t need to take care about it. To know how to change the measurement range setting, try to configure to use 10 nA
current minimum measurement range with AUTO range operation.
Step 1.
Press
repeatedly until Single View for Channel 2 is shown in the display.
Step 2. Press
to show Range Sub-Panel. (If you can’t see
change the keys shown in Assist keys.)
(1) Press More... (if necessary)
Step 3.
Rotate and press
in Assist keys, press
to
(2) Press Hide Sweep
to edit the channel 2 current minimum measurement range, and then select
to set it to 10 nA.
(1) Rotate and press
to edit
Current Minimum Measurement Range
(2) Press 10nA
Agilent B2902/12A Precision Source/Measure Unit
If you’d like to fix the measurement range, you can select FIXED range operation as below.
Step 4.
Rotate and press
to edit the channel 2 current measurement range operation. Then Select
to set it to FIXED.
(1) Rotate and press
to edit
Current Measurement Range Operation
(2) Press FIXED
Configuring the measurement trigger delay time
The trigger parameters including the measurement trigger delay time and the trigger period can be displayed in Trigger
Sub-panel in Single View, although Range Sub-Panel is shown at this moment. In the default setting, the trigger type is set
to the automatic trigger type (AUTO) so that you don’t need to specify these trigger parameters.
If you’d like to specify the measurement trigger delay time, take the following steps.
Step 1.
Press
repeatedly until Single View for Channel 1 is shown in the display.
Step 2. Press
to show Trigger Sub-Panel. (If you can’t see
change the keys shown in Assist keys.)
(1) Press More... (if necessary)
Step 3.
Press
in Assist keys, press
(2) Press Show Trigger
to edit the channel 1 trigger type, and then select
(1) Press
(2) Press SYNC
to set it to SYNC.
to
Agilent B2902/12A Precision Source/Measure Unit
Step 4.
Rotate
to select Channel 1 Trigger Parameters and set them up as below.
(Source Trigger Count: 101, Measurement Trigger Count: 101, Measurement Trigger Delay Time: 100ms)
Note) Source and Measurement Trigger Count should be the same number as Sweep Points.
Step 5.
Press
to show Single View for Channel 2 is shown in the display.
Step 6.
Rotate and press
to edit the channel 2 trigger type, and then select
(1) Rotate and press
Trigger Type
Step 7.
Rotate
to edit
to set it to SYNC.
(2) Press SYNC
to select Channel 2 Trigger Parameters and set them up as below.
(Source Trigger Count: 101, Measurement Trigger Count: 101, Measurement Trigger Delay Time: 100ms)
Note) Source and Measurement Trigger Count should be the same number as Sweep Points.
Now you’ve configured 100 ms measurement trigger delay time.
Agilent B2902/12A Precision Source/Measure Unit
Viewing the list of measurement results
The measurement results including the measurement time stamp can be referred by the following steps.
Step 1.
Step 2.
If you aren’t on the top of the Function menu, press
repeatedly to return to the top level.
On the top level of the Function menu
Any tree structure can’t be seen
In the middle level of the Function menu
Some tree structure can be seen
If you’d like to see the list of measurement results, press
, then press
Measure Result dialogue.
(1) Press Result
(2) Press Measure
Step 3.
Rotate and press
(1) Rotate
field
Step 4.
to select Channel field. Then press
to select Channel
Rotate and press
(1) Rotate and press
Data field
(2) Press Ch 2
to select Data field. Then rotate
to select
to select Channel 2.
to scroll the data list.
(2) Rotate
or press Assist key
to scroll the list
to open