Aehr launches FOX-CP wafer-level test & reliability screening system

In booth 4046 at the SPIE Photonics West 2019 event in San Francisco (5–7 February), Aehr Test Systems of Fremont, CA, USA has launched the FOX-CP low-cost single-wafer compact test and reliability verification system for logic, memory and photonic devices as the newest addition to its FOX-P product family.

“The new single-wafer FOX-CP system is integrated with a wafer prober and performs wafer-level testing and reliability cycling for logic, memory and photonic devices,” says president & CEO Gayn Erickson. “This newest addition to our FOX-P product family is optimal for test times ranging from minutes to a few hours or where multiple touchdowns are required to test the entire wafer. It complements the capabilities of the FOX-XP and FOX-NP systems, which are optimal when the test time is measured in hours or days and the full wafer can be tested in a single touchdown. The FOX-CP system offers a low-cost integrated package for both initial evaluations and production applications,” he adds.

Picture: The new FOX-CP test and reliability verification system.

“We are very optimistic about the silicon photonics and photonics sensors markets and believe they will be significant growth drivers for Aehr,” Erickson continues. “The rapid growth of integrated optical devices in high-performance servers and data centers, mobile devices, automotive applications and now wearable biosensors is driving substantially higher requirements for initial quality and long-term reliability, and the requirements are increasing with every new product generation,” he adds. “These new applications are driving an entirely new level of quality and reliability expectation for these systems and pose a significant long-term growth opportunity for Aehr.”

The FOX-CP single-wafer test system reduces test cost by functionally testing wafers during reliability screening to identify failing logic/memory/photonic die before the die are integrated into their final package. This integrated test system with wafer handling and stepping capabilities utilizes Aehr’s custom FOX WaferPak contactor and wafer prober available with thermal chucks to support a wide range of wafer power requirements. Key features of the FOX-CP include:

2048 ‘Universal Channels’ per wafer, enabling massively parallel test;
an innovative Universal Channel architecture, where any channel can be any function - I/O, Device Power Supply (DPS) or Per-pin Precision Measurement Unit (PPMU);
configurable with Universal Channel Modules, High Voltage Channel Modules or High Current Channel Modules;
the ability to perform single-touchdown or multiple-touchdown wafer probing;
available as an integrated solution with prober and custom-designed WaferPak Contactor; and
compatible with industry-standard wafer probers and probe cards.

Photonics applications

The FOX-CP system features unique capabilities for testing and reliability screening of vertical-cavity surface-emitting laser (VCSEL) arrays for 3D sensing applications and silicon photonics for 5G communications applications, including:

testing tens of thousands of arrays per wafer with amps of current per array;
stabilizing lase and identifying infant mortalities through extended stress/test programs; and
electrical and go/no-go optical detection.

One application is to conduct single-touchdown sampling test to confirm that the processing of the wafer is within specified limits and the yield exceeds minimum requirements. The large number of 2A channels (4A with pulsing) available enables a large sample size (as many as 1024 die) with a single touchdown, while providing an individual power supply per die. Individual power supplies per die enable maximum monitoring for device reliability characterization.

Another application is to perform multiple-touchdown (stepping) aging of the full wafer to stabilize the lasing parameters of the die. The large number of high-current power channels can reduce the number of steps by an order of magnitude and increases production throughput. Stabilizing/aging the lasers allows higher-bandwidth performance of the end product, since the laser parameters can be matched and don’t change over time and bring the laser parameters into the narrow range required for effective control of the devices.

FOX-P platform

The FOX-P Platform is Aehr’s next-generation multi-wafer and singulated die/module test solution that is capable of functional test and burn-in/cycling of photonics devices, flash memories, microcontrollers, sensors and other leading-edge ICs before they are assembled into single- or multi-die stacked packages. The FOX wafer-level systems utilize Aehr’s FOX WaferPak contactors, which provide cost-effective solutions for making electrical contact with a full wafer or substrate in a multi-wafer environment. The configuration with the DiePak Carriers enables burn-in of singulated die and multi-die modules to screen for defects in both the die and the module assembly process. The resulting known-good die, single-die or stacked-die packaged parts can then be used for high-reliability and quality applications such as enterprise solid-state drives, automotive devices, highly valuable mobile applications, and mission-critical integrated circuits and sensors.

The key features of the FOX-P Platform that contribute to cost-effectiveness include the ability to provide up to 2048 ‘Universal Channels’ per wafer or DiePak carrier, which allows the system to test all the devices on the wafer or DiePak carrier in parallel. The innovative Universal Channel architecture allows any channel to be any function: I/O, Device Power Supply (DPS) or Per-pin Precision Measurement Unit (PPMU). This enhanced architecture now allows customers to perform per-pin parametric testing, more extensive digital pattern test with deeper data stimulus/capture memory (32M per pin), and deeper scan (768M) optimized for BIST/DFT testing. A single FOX-XP test system may be configured with up to 18 blades of wafer test resources, enabling up to 18 wafers to be tested simultaneously. The footprint of the 18-wafer test system is similar to the footprint of typical automatic test equipment (ATE) that can only test one wafer at a time. The highly integrated 2-blade FOX-NP system has a very small footprint and is designed to be easily integrated into product design, reliability and test lab applications. The new FOX-CP single-wafer system is integrated with a wafer prober and performs wafer-level testing and reliability screening.

The FOX-CP system is available now for order and for shipment with standard lead times.

Tags: Semiconductor test instrument

Visit: http://spie.org/photonics-west.xml

Visit: www.aehr.com