Die-Level Test Sockets with Conversion Kit
Optical inspection and electrical test in one flexible platform
RTI’s die-level test sockets provide open-top access for SIL, EMMI, hand test, and electrical characterization. Devices reflowed onto PCB coupon boards are supported with a fixed pin-block base, while a drop-in conversion kit quickly reconfigures the socket to a floating base for packaged ICs and WLCSP devices. This dual setup eliminates hardware swaps and maintains consistent optical and electrical access across test methods.
Die-Level Test Sockets with Conversion Kit
Optical inspection and electrical test in one flexible platform
RTI’s die-level test sockets provide open-top access for SIL, EMMI, hand test, and electrical characterization. Devices reflowed onto PCB coupon boards are supported with a fixed pin-block base, while a drop-in conversion kit quickly reconfigures the socket to a floating base for packaged ICs and WLCSP devices. This dual setup eliminates hardware swaps and maintains consistent optical and electrical access across test methods.
Built for Die-Level Testing and Inspection
RTI’s die-level test sockets are engineered for precision, flexibility, and repeatable performance across inspection and electrical test environments. Whether performing advanced failure analysis or routine hand testing, this solution streamlines the process and maintains consistent hardware across configurations.
These open top test sockets support Solid Immersion Lens (SIL) and EMMI inspection methods that require direct physical access to the die. They also accommodate standard hand test applications through a convertible design that allows switching between solid and floating base configurations as needed.
- Supports high-density and interstitial pin layouts down to 0.3 mm pitch.
- Provides 100% unobstructed access to devices reflowed onto PCB coupon boards.
- Floating base is compatible with open-top FA lids, RTI sapphire window lids, and clip-on removable lids.
- Tooling holes on the PCB coupon board align with dowel pins in the socket base to ensure precise board placement and reliable pogo pin contact.
- Supports both hand testing and die-level inspection using the same socket hardware, ensuring consistent setups across test methods.
- Relief cutouts in the socket base provide clearance for backside SMT components on the coupon board.
Why Choose RTI’s Die-Level Sockets?
Consistency Across Test Applications
Use the same socket body and DUT board to test packaged ICs and die-level devices on coupon boards. This unified setup ensures consistent results across FA, characterization, and hand test environments.
Full Device Access
The open top configuration provides complete access to the device surface—essential for SIL, EMMI, or probe-based inspection tools used in failure analysis and reliability testing.
Cost-Effective and Scalable
One socket design supports multiple test needs. Using the same hardware across labs and teams reduces delays and equipment mismatches when the same DUT must be tested in different formats or locations.
Why Test PCB Coupon Boards?
No Optical Obstruction
When the DUT is reflowed onto a coupon board, nothing sits above the device surface. This allows close-proximity optical tools such as SIL objectives to contact the die without interference.
Cleaner Optical Data
By eliminating sapphire glass between the lens and the DUT, optical distortion is reduced and edge-to-edge scan quality improves.
Footprint Flexibility
Coupon boards can be standardized with universal gold-plated pads to support multiple device types. They can also adjust pitch between the DUT and the socket’s pin array to enable consistent contact across form factors.
Where This Socket Shines
Failure Analysis
Supports advanced inspection techniques such as SIL microscopy, which requires direct physical contact with the die.
Hand Testing
The conversion kit installs quickly while maintaining DUT alignment, making it easier to swap devices between test cycles without compromising precision.
Sensitive Test Methodology
Using the same socket and PCB across different applications reduces variability and minimizes the risk of false failures caused by mismatched setups.
PCB Coupon Board Setup
In this setup, the test socket functions as a spring pin block with either a universal or DUT-specific pin array to match the device footprint. PCB coupon boards with standardized tooling and mounting holes are secured to the socket base using hand-tightened screws.
Pins on the socket make contact with pads on the bottom of the coupon board, which connect to the leads or balls of the DUT. Since each DUT is reflowed onto the board in this configuration, no lid is required to apply compression force. This frees the working area surrounding the device for unobstructed access.
For more information, contact us or download the info sheet here.
Conversion Kit for Packaged Device Testing
The conversion kit includes a floating plate drilled to match the DUT’s dimensions and pin footprint, along with a screw-down cover to secure it to the socket base. This setup converts the standard die-level test socket into a traditional hand-test configuration for use with individual packaged ICs or WLCSP devices not reflowed onto coupon boards.
The floating plate rests on its own set of extended spring pins, separate from the main test pins. This allows balled devices to self-align to the recessed pin tips before compression is applied. A screw-down lid—open top, closed top, or sapphire windowed—applies the necessary force during testing.
For more information, contact us or download the info sheet here.
Lid Options for Coupon Board Setup & Conversion Kit Setup
Option 1: No Lid
This is where the socket’s design sets it apart. When the DUT is reflowed onto a coupon board and the board is mounted directly to the socket base, no lid is required to apply compression force. This leaves the area surrounding the DUT fully accessible for edge-to-edge SIL inspection, probing, or other techniques requiring this additional working space. In this configuration, nothing sits higher than the silicon.
Option 2: Low Profile Screw-Down Lids
These lids attach to the socket body with two or four screws. Their low-profile design adds only a few millimeters to the total height, making them ideal for optical inspection setups where a close working distance to the DUT is needed.
Lid Variants:
Open Top
Provides physical access to the top of the DUT. The opening is slightly smaller than the DUT footprint, allowing the lid to apply compression force while maintaining access to the die.
Closed Top:
Applies compression force across the entire surface of the DUT. This version has no cutouts and is typically used when physical access is not required during test.
Sapphire/Quartz Window:
Allows optical but not physical access to the exposed die. Often used with the conversion kit and WLCSP devices, these lids offer full-surface visibility and the optical clarity needed for emission microscopy and other advanced inspection techniques.
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