Wafer Chuck Guide for Probe Tables

A wafer chuck is used to hold wafers or chips in place when they are detected. The chuck may use a mechanical fixture or a vacuum can be applied from the back of the wafer. Vacuum wafer holders are preferred in the majority of applications.

In general, chucks are slightly larger than the size of the wafer and have concentric vacuum rings to accommodate substrates of different sizes.

In general, wafer chucks are made of aluminum and plated with nickel or gold, but they are also available in steel if business application development requires it. They usually have a flatness range of 4 mm to 8 mm.

When configuring probe stations, operators can use a variety of chuck types depending on their application. Examples include.

HF/microwave chucks, high voltage chucks, package part holders, lifting pin chucks, MEMS chucks, heated chucks

There are a variety of options available with Probe Table Wafer Chucks

Thermoelectric chucks:

Often, chucks must be able to heat or cool the substrate. This requires a "hot chuck", sometimes referred to as a "hot" chuck. Hot Chucks are capable of covering a wide temperature range, with the standard range being ambient to 200 °C. In order to prevent exposing the operator to hot surfaces at higher temperatures like 300 or 400 degrees Celsius, the probe arms, pressure plates, and chuck adapters should be carefully chosen.

A thermal chuck with cooling capabilities requires coolers and coolants that are isolated from their surroundings. There are many types of coolants such as water, nitrogen, Galden, and clean air.

Environmental chambers located locally:

In order to shield the device from external factors and accurately detect temperatures, it is necessary to use a local development environmental chamber (LEC). These specialized chambers provide controlled conditions, free from frost, light, and EMI interference. The designer must ensure that the chamber not only accommodates the device under test, but also allows for unrestricted movement of the manipulator and probe arm during testing.

Chucks with two sides:

Occasionally, testing requires access to both the front and back of the device under test. It is possible to configure these chucks with openings on the bottom to allow optical inspection of the chip or contact with the probes, depending on the needs of the test application.

Chucks with high frequency:

It is common to use HF Chucks to hold a wafer and two calibration substrates,micromanipulator or a calibration substrate and a contact substrate. They are equipped with vacuum manifold kits that provide independent vacuum control for three quadrants. These are designed for testing high frequency devices.

Chucks with high power:

These probe station are designed for high power probing systems with voltages up to 3 kV or 10 kV with coaxial, triaxial, or Kelvin connectors.

Fixtures for encapsulated parts:

As a variation of the flat chuck, package part fixtures are used to hold package parts,test probe substrates, and printed circuit boards. They can also hold wafer chucks for testing entire wafers and package assemblies simultaneously.

Chucks with lift pins:

Robotic arms transfer wafers using Chucks with lifting pins to enable fully automated problem solving scenarios. The lifting pins allow the student to handle material information safely and repeatably as the wafer is lifted off the chuck base. Various mechanical, pneumatic, and electrical systems can be used to simultaneously raise or lower wafers or substrates.

Chucks made of MEMS:

In vacuum chambers, these chucks can be tilted in an x or y direction for inspection of specific regions of a MEMS device that are not easily accessible from above or below.

For your inspection application or specific requirements, you can use a chuck or customized solution.