DD288235A5 - DEVICE FOR WAFER TEST UNDER HIGH FREQUENCY CONDITIONS - Google Patents

Abstract

The invention relates to a device for wafer test under high-frequency conditions. The apparatus for wafer test under high frequency conditions is used to realize a Meszkopfes for the functional testing of high-frequency circuits in the wafer association with a high number of connections, on the one hand the safe electrical contact between the bonding pads of the chips and the tester and on the other the loss and distortion low transmission of high-frequency signals in the Testing allowed. The device consists of four arranged on a Formstueck plates with Masseflaechen and coplanar lines, wherein on the inner conductors of Koplanarleitungen on one side probe needles and on the other side inner conductor of coaxial connectors are contacted {Wafertest; Meszkopf; High-frequency circuit; Bond Island; Anschluszzahl; Contact; Masseflaeche; coplanar; Inner conductor; Probe needle; coaxial}

Description

For this 2 pages drawings

Field of application of the invention

The invention relates to a measuring device for testing of Haibleitorchips for use in high-frequency technology in the wafer assembly, which can be applied in the functional test between the cycle I and the cycle II in the production in the semiconductor industry.

Characteristic of the known state of the art

The known technical solutions can be in coaxial and coplanar probe cards, the probing on the basis of ceramic needle carriers, metallic needle carriers, soldered needles or kink-wire principle, and differ in alternative solutions.

In US PS 4791363 a ceramic needle carrier is described which carries on one side with a continuous ground plane and on the other side a microstrip line. In addition to a straight probe needle, which serves the high-frequency feed, a needle is additionally applied to the ground surface. The connection to the tester is formed by directly contacted coaxial cable or coaxial connector. The good high-frequency properties in this solution is offset by a high manufacturing cost and a low bond density.

in US PS 4161692 a ceramic needle carrier is described, which is metallized only on its underside by means of thick film technology in order to keep the crosstalk low. At this metallization layer, a straight needle is contacted with angled tip. The achievable density on the Nadelkarto is low.

In the patent DE 4731577 a coaxial needle card is described with ceramic needle carriers, wherein the connection between the provided with a microstrip line needle carriers and provided with microwave connectors connector ring is made by coaxial cable. Thus, the mentioned disadvantages of the ceramic needle carrier also occur here.

In US PS 4686463 a shielded probe card is described with directly contacted needles, which is made by coaxial connector, the vertical connection to microstrip lines on a disposed below the support plate dielectric plates. At the other end of the microstrip line attaching the needles, wherein the possible spring travel of the needles is extremely small due to their brevity, so that the height tolerance is critical. The use of unshielded strip cables increases the risk of crosstalk.

No. 4,727,339 describes a solution similar to US Pat. No. 4,683,463, in which case the coaxial connectors were mounted at an angle to the strip lines in order to reduce the risk of reflection. There are also the disadvantages mentioned here.

In DE OS 2525166 a contact probe device is described according to the buckling wire principle, in which coaxial cables embedded in grooves of a carrier plate are used. Due to the dense pattern of the stripped inner conductor, however, a coupling can not be ruled out.

In the US PS 4593243 a probe card is described in which the high-frequency signal lines are formed as coplanar lines and geometrically shaped so that a defined characteristic impedance is achieved. The needles are mounted in metallic needle holders, or the needle carrier are designed so that a contact tip is formed. The achievable density of the arrangement is limited.

In the US PS 4764723 an alternative test head is presented, which has a multi-level structure with polyamide as an insulator layer, wherein the contacting of the chips is to take place directly on the coplanar strip lines. The manufacturing cost of such a solution is high, and in terms of contacting problems are unavoidable.

In DE OS 3705714 an alternative solution is likewise offered, in which the testing is carried out with a test chip designed mirror-inverted with respect to the bonding pad configuration. The Horstellungsprozeß for such a chip corresponds to that of the chip to be tested.

The aim of the invention is a test head for the functional testing of high-frequency circuits in the wafer assembly, with a high number of ports and density, a good contact behavior and a loss and distortion-free signal transmission is aimed at a reasonable manufacturing cost.

Explanation of the essence of the invention The object of the invention is the realization of a measuring head for the functional testing of high-frequency circuits in Wafer bond, on the one hand, the secure electrical contact between the bonding pads of the chips and the tester and the

others the loss and distortion-free transmission of high-frequency signals allows.

Compared to the known technical solutions is a high quality of transmission and a high connection density

sought.

According to the invention, the device consists of a molded piece which is either metallised or consists entirely of metal

the shape of a flat truncated pyramid, wherein the horizontal surface is formed as a recess. On the side surfaces of the truncated pyramid four metallized plates are arranged on both sides, wherein the upper metallization is formed as a ground plane and is contacted with the electrically conductive form fitting.

The lower metallization is formed as a plurality of coplanar lines, wherein the ground lines of the Coplanar lines are electrically connected by means of plated-through holes with the ground plane. On the recess of the Fitting facing side of the coplanar lines are provided with probe needles, which correspond to the configuration

the unit to be scanned are arranged. The outer ends of the inner conductors of the coplanar lines are conductive with the

Inner conductor connected by coaxial connectors and their housing are mechanically and electrically connected to the ground plane

contacted.

embodiment Reference to an embodiment of the invention will be explained in more detail according to the figures 1 to 4. Mean in it

Fig. 1: View of the device from the wafer side Fig. 2: sectional view of the device Fig. 3: sectional view of the compound

Coaxial Connector Flatte Fig. 4: View of the connection point

Coaxial connector plate from the wafer side.

Starting material for the production of the plates 1 is a ceramic with good high-frequency properties, ζ. B. Al ₂ O ₃ ceramic. The ground plane 5 and the coplanar lines 2 are realized by means of thin-film technology or chemical-reductive metal deposition and subsequent structuring. Subsequently, the plates 1 are arranged electrically conductive on the fitting 6, z. B. by gluing with a Loitkleber. At the ground surface 5, the housing of coaxial connectors 4 are mechanically and electrically contact part, z. B. by soldering and the inner conductor 7 of the coaxial connector 4 with the inner conductors of the coplanar lines 2 soldered. Finally, the adjustment and mounting of the probe needles 3 takes place on the coplanar lines 2.

Claims (2)

An apparatus for wafer testing under high frequency conditions, characterized in that four double-sided metallized plates (1) of insulating material, wherein the upper metallization of these plates (1) as a ground surface (5) and the lower metallization formed as a plurality of coplanar lines (2) in that the ground lines of the coplanar lines (2) are electrically conductively connected to the ground plane (5) by vias, by holding the plates (1) in the form of a flat truncated pyramid through a rectangular shaped recess (6) in the shape of a flat truncated pyramid the inner recesses of the coplanar lines (2) probe needles (3) are conductively secured so that the outer ends of the inner conductors of the coplanar lines (2) with the inner conductors (7) of coaxial connectors (4) and their housing with the ground plane (5) are conductively connected and that the connection of the ground surfaces (5) of the four plates (1) is realized by a metallization of the underside of the molding (fi). 2. Apparatus for wafer test under high frequency conditions according to claim 1, characterized in that the shaped piece (6) is preferably made of a metallic material.