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Can your present equipment solve these key
power device evaluation challenges?
Insufficient measurement capability
Power devices require characterization across their entire operating region, which can range from
nanoamps or microvolts up to more than one thousand amps and thousands of volts. In addition, the
ability to perform narrow (microsecond range) pulsed IV measurements is also important to prevent
device self-heating that can distort measurement results. Lastly, characterizing the switching speeds
of power devices necessitates some means to characterize gate resistance (Rg), gate charge (Qg) and
junction capacitances at biases of several thousand volts. These parameters have become extremely
important as end application switching frequencies have continued to increase. However, traditional
measurement equipment cannot meet all of these requirements.
Verification of power device reliability
Since many power devices are used in harsh environments and mission-critical applications, they have
to be extremely reliable. Characterizing performance under a wide range of operating temperatures
as well as near the safe operation area (SOA) is crucial to meeting reliability targets. Unfortunately,
temperature testing is time consuming, difficult and prone to oscillation issues caused by long cables
when an external thermal chamber is used. SOA testing typically requires dynamic testers, which are
difficult to use and lack sufficient accuracy.
Issues with novel new device (SiC, GaN, Ga
2
O
3
, IGBT) characterization
New wide band gap materials such as SiC, GaN and Ga
2
O
3
show great promise for emerging high
power applications because of their ability to withstand large voltages and their fast switching
speeds. IGBTs are becoming increasingly important as electronic switches for a variety of applications.
Characterization of large breakdown voltages (up to 10 kV), high currents (hundreds of amps), gate
charge, junction capacitances under high voltage DC biases (up to 3000 V), device temperature
dependency and the GaN device current collapse effect are measurement capabilities that are crucial
to bringing these new devices to market as quickly as possible.
No curve tracer hardware support or feature enhancements
Until recently, curve tracers have been the de facto standard tool for power device evaluation. However,
conventional curve tracers do not possess the abilities necessary to evaluate modern power devices.
They lack crucial capabilities such as transfer curve or junction capacitance characterization, they
cannot generate sufficiently short pulse widths and they do not possess sufficient accuracy. Extracting
PC-compatible data from curve tracers is also inconvenient and time consuming.
Safe and efficient packaged device testing
A test fixture that is both safe and easy to use is very important for packaged power device evaluation.
However, the lack of a standard test fixture for high-power devices has forced many people to create
their own solutions, which become difficult to manage when multiple package types need to be tested.
Moreover, temperature dependent testing (which is mandatory for power device evaluation) cannot be
done safely and reliably.
Power device development costs
The ability to probe devices on-wafer greatly saves both time and money by eliminating the need to
package the devices beforehand. However, on-wafer power device measurements have previously not
been easy to make. Not only the time and cost of supporting the on-wafer measurement environment
but also the safety of the on-wafer measurement environment are big concerns.