Membrane probing method using improved contact
View Patent ↗A method of probing an electrical device using a membrane probing system having an improved contact. A membrane probe forms a contact having a ridge with a pair of inclined surfaces defining an acute angle such that, when pressed into an electrical pad of a device to be tested, the ridge penetrates into the electrical pad, shearing away any oxide on the surface of the pad. The device may then be tested.
1. A probing assembly for probing an electrical device comprising:
(a) a pair of contacts formed by locating conductive material within a plurality of depressions of a sacrificial substrate, each contact having a length and a contacting portion located nearer a first end of said length than a second end of said length, said contacting portions spaced apart but nearer to each other than said second ends are to one another and sufficiently near to each other to enable simultaneous contact with a single contact pad of said electrical device;
(b) each contact being electrically connected to a corresponding conductor; and
(c) an elastic assembly operating in respect to each contact to urge each contact, wherein each of said contacts is supported by a single continuous surface of said elastic assembly, when placed into pressing engagement with said electrical device, into tilting motion so that each contact is driven in accordance with said tilting motion into lateral scrubbing movement across said device, so that said lateral scrubbing movement of a first contact is opposite to that of the other contact of said pair.
2. The probing assembly for claim 1 wherein said elastic assembly comprises an elastomeric member having a first surface substantially resisting outward displacement normal to said first surface.
3. The probing assembly of claim 1 wherein each one of said contacts is tiltable independently of the other one of said contacts.
4. The probing assembly of claim 1 further including a base arranged substantially parallel to a surface of said electrical device, said elastic assembly being coupled to said base so as to enable portions of said surface of said elastic assembly to automatically tilt relative to said base in response to pressing engagement between said pair of contacts and said electrical device.
5. The probing assembly of claim 1 wherein each of said contacts has a downwardly protruding contacting portion.
6. The probing assembly of claim 1 wherein a first contact of said pair of contacts is electrically connected to a force connection of a Kelvin testing arrangement and a second contact of said pair of contacts is electrically connected to a sense connection of said Kelvin testing arrangement.