Product category:
ATE Systems
News Release from: Keithley Instruments | Subject: Automated Characterisation Suite
Edited by the Electronicstalk Editorial
Team on 01 May 2008
Characterisation software addresses
wafer level
Reliability test and data analysis tools allow ACS-based test systems to produce lifetime predictions as much as five times faster than traditional WLR test solutions.
Keithley Instruments has enhanced its Automated Characterisation Suite (ACS) software to include optional wafer level reliability (WLR) test tools for semiconductor reliability and lifetime prediction testing applications Version 4.0 builds on the ACS software's existing single- and multiple-site parallel test capabilities, adding a database capability, as well as software tools and optional licenses for the new reliability test module (RTM) and ACS data analysis capabilities
This article was originally published on Electronicstalk on 11 Jan 2008 at 8.00am (UK)
Related stories
Software upgrade brings new semiconductor options
Keithley's Automated Characterisation Suite, V3.2 contains ready to run applications for its 4200-SCS, 2600 System SourceMeter instruments and other SMU-based systems.
Microwave switch system aids HF testing
Keithley Instruments' Model S46 microwave switch system is the first system of this type that can be ordered in a wide variety of configurations for off-the-shelf delivery.
Together, the new reliability test and data analysis tools allow ACS-based test systems to produce lifetime predictions as much as five times faster than traditional WLR test solutions.
By accelerating WLR testing during the technology development, process integration, and process monitoring phases of creating new integrated circuits, ACS systems can reduce time to market for new products significantly.
ACS-based test systems have the hardware configuration flexibility necessary to address a wide range of semiconductor characterisation needs at the device, wafer, or cassette level.
Further reading
First GPIB-controlled autotuning TEC tester
The Model 2510-AT autotuning TEC SourceMeter from Keithley Instruments is designed for testing and control of thermoelectric coolers (TECs) used in telecomms laser diode modules (LDMs).
Single-box L-I-V test solution for pulsed lasers
The Keithley Instruments Model 2520 pulsed laser diode test system is designed for electrical characterisation of laser diodes in either the chip/bar state or in finished modules.
Data acquisition upgrades to 32bit ActiveX
Keithley Instruments has released version 4.0 of its test and measurement data acquisition environment TestPoint.
They can incorporate either Keithley's Series 2600 System SourceMeter instruments, the company's Model 4200-SCS Semiconductor Characterisation System, or both.
Wafer level reliability (WLR) testing is used to predict reliable lifetimes for semiconductor components such as transistors, capacitors, and interconnects.
These tests, performed on on-wafer test structures, can reveal critical reliability information during research and development; similar tests are used to monitor the consistency of manufacturing processes once devices go into full production.
WLR testing is designed to accelerate failure mechanisms by stressing devices with elevated levels of voltage, current, and/or heat.
To determine acceleration factors, a set of devices will undergo various levels of stress over time.
Unlike traditional WLR systems, which stress-test one device at a time, the new WLR tools in the ACS software allow testing multiple devices in parallel while applying different stress conditions (voltage or current) to each device.
New technical challenges, including the continuing scaling of film thicknesses and the increasing importance of device reliability in high temperature applications, have made the need for parallel WLR testing more critical than ever.
Parallel testing approaches allow engineers to extract the lifetime acceleration factors by testing a single structure made up of several devices.
Many of the test structures already used in traditional WLR testing are compatible with parallel test techniques, making it possible to increase system throughput by a factor of 2-5x without the need to modify their test structures.
However, this level of true parallel WLR testing is only possible with test system architectures in which each pin has its own dedicated source-measure unit (SMU).
ACS-based test systems configured with multiple Series 2600 System SourceMeter instruments are the only commercial solutions capable of providing this level of SMU-per-pin testing flexibility.
ACS simplifies networking Series 2600 instruments into a highly flexible and dynamically reconfigurable array of SMUs by connecting their onboard test script processors (TSP) via a TSP-Link virtual backplane.
This system architecture makes it possible for the application to instruct the SMUs either to work together as a large, tightly co-ordinated group or as several smaller groups that work in concert to test several devices.
The Series 2600's onboard processors and virtual backplane combine with these instruments' best-in-class measurement speed to provide precision source/measure timing, which is critical to capturing the details of fast-moving breakdown events.
ACS-based systems can be configured with anywhere from two to more than forty high power Keithley SMUs, which can source and/or measure 200V or 1.5A.
The new reliability test module (RTM) option available with ACS 4.0 is a powerful stress/measure sequencing tool that provides an interactive interface for testing device reliability (HCI, BTI, etc), gate oxide integrity (TDDB, JRAMP, VRAMP etc), and metal interconnects (EM).
The module's flexible test sequencing capabilities support pre- and post-testing, as well as intra-stress testing and stress monitoring.
It's designed in compliance with JEDEC standard test methodologies (such as JESD61 and JESD92), but it also offers the flexibility needed to create new test routines quickly to characterise advanced nanoscale structures.
During reliability testing, the raw test data can be logged to the database and/or plotted in real time.
These real-time plots offer reliability engineers a "sneak peek" at a test's outcome before its completion, which allows them to judge whether time-consuming tests are on track to deliver meaningful results.
The optional data analysis module imports test results from the database, and then applies the rules and models defined in the analysis project the reliability engineer selects.
Once an analysis process has been defined, it can be reused to analyse newly imported data easily.
For those who are new to WLR testing, this option eliminates the need to create custom analysis software and to manipulate data manually with spreadsheets.
However, for those who have already developed their own custom analysis software that they wish to continue using, ACS 4.0 provides software tools that simplify extracting data from the database.
The data analysis option supports standard analysis techniques like normal fitting, acceleration, and distribution models, including Lognormal and Weibull.
Models can be easily reorganised and edited to create new analysis processes.
A built-in scripting language also lets users define their own models easily.
The reliability formulator tool provides a variety of advanced functions, including modelling, line-fitting, standard parametric extractions, and standard math functions that allow custom data manipulation.
Both the ACS 4.0 test executive and the data analysis option allow for offline installations (that is, on a PC not linked to the source-measure hardware).
For test environments where multiple users or departments share access to the same ACS hardware, this allows convenient access to the software tools for building test sequences and reviewing and analysing data offline without tying up the test system's workstation.
When purchasing the data analysis option, extra licenses are available to allow multiple offline installations; the ACS test executive can be installed offline without an extra license.
ACS 4.0 software can be used to drive test systems made up exclusively of Series 2600 System SourceMeter instruments, just the Model 4200-SCS semiconductor characterisation system, or a combination of both.
With the unique capabilities of each integrated into a single system, reliability engineers can bring together the advantages of high speed, SMU-per-pin flexibility (Series 2600) and the high power pulse I-V testing capability (Model 4200-PIV) needed to characterise interface traps and isothermal behaviour, which are common in new gate stack technologies.
Typically, Model 4200-SCS applications are found in the reliability lab, while the Series 2600's high speed makes these instruments invaluable in process development, process integration, and process monitoring applications.
An ACS-based system that combines both instrument types simplifies a device's transition from the lab to the fab by allowing engineers to use the same characterisation tool in both environments.
Keithley's ACS-based test systems are designed to interoperate with a wide range of hardware components typically used in WLR testing, including popular wafer probers and probe card adapters, hot chuck controllers, single- and multiple-site probe cards, and high temperature probing options.
Pricing for Keithley's ACS integrated test systems is based on the particular configuration and licensing and customisation options desired.
Systems and software upgrades are available immediately. Request a free brochure from Keithley Instruments ...
• Keithley Instruments: contact details and other news
• Email this article to a colleague
• Register for the free Electronicstalk email newsletter
• Electronicstalk Home Page
Search the Pro-Talk network of sites
