Greater support for reliability/high power device test

Keithley Instruments has upgraded the capabilities of its Automated Characterization Suite (ACS) Test Environment. ACS Version 4.4 is designed for use with a number of the company’s instrument and system configurations used mainly for automated device characterization and reliability analysis. It supports a newly enhanced reliability test option (Model ACS-2600-RTM), as well as expanded ultra-fast bias temperature instability (BTI) testing capabilities, high current testing of power components, and new project libraries designed for high voltage reliability, charge pumping, pulse-stress reliability, and stress migration testing applications. The latest revision also adds support for Windows® 7 operating systems, which simplifies staying current with a facility’s PC/system OS requirements.

New Reliability Test Option
ACS V4.4 supports an updated optional reliability test module (Model ACS-2600-RTM) that simplifies creating and executing complex stress-measure-analyze test sequences used in device reliability tests, such as HCI, TDDB, NBTI, J-Ramp, and more. This updated software module gives semiconductor test engineers doing device reliability testing and analysis in R&D or production test environments the tools they need to test more productively, whether they’re characterizing single devices or managing high device count test applications. ACS helps users manage complex system instrumentation configurations, quickly define test parameters common to large groups of devices or many sub-groups, execute tests with run-time results feedback, and begin analyzing large datasets of measurement results sooner.

In order to respond to the high-speed behaviors associated with semiconductor device failure mechanisms and produce the masses of data associated with reliability testing of multiple devices in parallel, each source measurement unit http://www.keithley.com/products/dcac/currentvoltage (SMU) instrument in a test configuration must not only be fast, but all SMU channels working as a group or several sub-groups must be fast as well. For reliability test applications of this type, the Model ACS-2600-RTM is designed to maximize the performance of Keithley’s Series 2600A System SourceMeter® instruments, which combine powerful embedded scripting capability (through the use of on-board Test Script Processors) with multi-unit integration via the TSP-Link® high-speed inter-unit communication bus. ACS leverages the inherent speed of Series 2600A instruments, accelerating the system reconfiguration process, uploading test conditions and scripts to the embedded processors in individual instruments, and beginning execution quickly. Test engineers have the flexibility of using ACS and the optional Model ACS-2600-RTM with individual Series 2600A units or with Keithley’s S500 Integrated Test Systems.

The updated reliability test module also provides other important advantages for device reliability testing. For example, dynamic limit current protects devices under test from severe damage by reducing the maximum breakdown current possible during the progress of the test sequence. In addition, device reliability test sequences can require hours, days, or even weeks to complete, producing enormous amounts of measurement data. The Model ACS-2600-RTM reliability test module provides compression techniques that allow the test system to capture the most important measurement results while continuing to make measurements over these extended periods.

Support for Additional Pulse-Measure Units for Ultra-Fast BTI Testing
Owners of Keithley’s Model 4200-SCS parameter analyzer can now make use of all six of the pulse-measure units (Model 4225-PMU) that system supports for ultra-fast bias temperature instability (BTI) testing. Previously, ACS supported operating a maximum of four units at once. The ACS V4.4 update allows testing more devices in parallel for higher system utilization and faster acquisition of BTI data.

Support for Keithley’s Newest SMU, Optimized for High Power Testing
The ACS V4.4 upgrade provides support for the Model 2651A High Power System SourceMeter instrument, the latest addition to the Series 2600A line. This instrument’s high current capability (up to 50A at 40V) is critical to labs and fabs involved in the development and production of vertical structure power components like insulated gate bipolar transistors (IGBTs http://www.keithley.com/data?asset=55786 ) and double-diffused metal-oxide semiconductors (DMOSs).

New Projects for Emerging Device Technologies
ACS V4.4 includes several turnkey test projects designed to address high voltage reliability, charge pumping, Wafer Level Reliability (WLR) with specified pulse/AC stress, and stress migration (reliability) testing. Many users will be able to employ these projects as provided; for others, they offer a starting point that can help them develop their own custom test projects more quickly.

ACS Test Environment Background
ACS combines multiple instruments used for semiconductor device characterization and parametric measurements into a unified test environment optimized for flexibility, speed, and productivity in testing and analysis. Its intuitive GUI helps novice users test devices productively almost immediately, regardless of their level of test programming experience. The GUI simplifies configuring test instrumentation, setting measurement parameters, making I‑V measurements, and displaying results. Even infrequent users can go from creating a new test setup to characterizing new devices in a fraction of the time older test development approaches require. Just as important, ACS provides all the tools needed to set up tests, analyze data, and export results—without ever leaving the ACS environment. ACS also simplifies integrating a variety of popular semiautomatic and fully automatic wafer probe stations into a test setup.