Xcerna DxV

The Cohu Xcerna DxV is a tester manufactured by Cohu / Delta Design. The Xcerna DxV belongs to the test and probe equipment category.^[1][2]

Automated test equipment generates electrical stimulus patterns and applies them to a device under test through a dedicated interface. The interface may be a socket that receives a packaged device or, for wafer-level probing, a probe card whose contacts touch the bond pads of each die. After the device responds, the tester compares the measured values with programmed limits and records a pass or fail result. Test programs, limit sets, and data logging are managed by the tester's computer-based control system, and thermal conditioning is frequently included so that devices can be tested at defined temperatures.

Test and probe equipment is used at the electrical evaluation stages of the semiconductor manufacturing flow, after device structures have been formed. Wafer probing is performed before dicing to sort functional dice, and final test is performed after assembly and packaging. The results produced by test equipment are used to grade devices and to supply yield information that feeds back into process control.

Test and probe systems are applied to integrated circuits and discrete semiconductor devices for design validation, production screening, and reliability testing. Functional testing verifies that a device performs the operations it was designed for, while parametric testing measures electrical characteristics such as voltages, currents, and timing.

Test applications also include characterization of device behavior across temperature and other operating conditions. Devices that pass test are graded and sorted into product classes according to measured performance.