16-Needle Mini-Probing Card

For Experiments with IC Prototypes
Specimen Stage "Module" for Experiments on integrated circuitry prototypes (stroboscopic experiments, voltage contrast, EBIC, OBIC). The IC is placed into a spring loaded catch-lock holder, which assures reproducible clamping.
A sub-miniaturized prober card with 16 needles folds down from the left, until it touches an adjustable mechanical stop. The pads, arranged around the periphery, are each contacted extremely gentle by one of the needles. The ultra-fine tungsten tips always touch the same place on the IC.
The only requirement in making the chip is, that the squares where the pads will be lithographed, must be defined in the image before writing. The rest of the structure can then be designed independently.
This "Mini-Probecard"-Module fits on nearly any SEM-specimen stage. Some chambers are suitable to group a small interferometer (20 mm x 20 mm travel) around the device. If the SEM has an air interlock loading mechanism which accepts specimens of 70 mm width and 40 mm height, then this module can also be inserted through there. The photograph shows the module in its configuration for a JEOL 6400, equipped with an interlock at the left.
On the right, there is the detachable needle-bending-jig, which allows to bend new needles precisely to shape. In the foreground, the lower half of this bending device. It fits the specimen holding square. The upper half of the bending jig is shown "open." These two halves allow to bend all 16 needles down 45 degrees in one stroke, accurately defined. After completing the bending operation, the whole right side of the jig is taken off, and the specimen holder is put back in place. Now, the specimen may be seated there.
Functional sketches
Preparing new Contact Needles: The 16 Needles are placed into the Vee-groves of the lower half of the mini-prober card, using a stereo light microscope, and then the upper half is tightened down (this automatically makes electrical contact). Instead of a specimen, the opposing piece of the bending "jig" is inserted, and the mini card is then turned to horizontal position until it touches the mechanical stop. Now, the bending frame is mounted at the left with two screws, and then closed down. This bends down all 16 Needles at once to the same angle.
16_prober_needle_module Contact module with bending frame mounted in left hinge, ready for bending. The mini card frame was turned down horizontal already, (turning in the right hinge)
In this view, the bending jig was taken out, and the specimen is now in the same place where before the lower half of the bending jig was attached. Now, the mini card frame can be turned down until the mechanical stop limits it. All 16 needles get in contact with the pads. A mini plug with 18 precision contacts is mounted at the rear of the specimen stage. The assembly contacts there. If the SEM has a large enough air interlock (70mm wide x 45 mm high), then this fully assembled device may also be inserted through it. It will then meet the 18 contacts, from where the cable bundle plus a faraday cup and ground are connected to the outside using a vacuum tight electrical feedthrough flange.

Pic.1: 16-Needle Mini-Probing Card

Pic.1: 16-Needle Mini-Probing Car

Dortmund Skyline