Multilayer wiring base plate and probe card using the same

Abstract

A multilayer wiring base plate includes an insulating plate including a plurality of synthetic resin layers made of an insulating material, a wiring circuit provided in the insulating plate, a thin-film resistor formed along at least one of the synthetic resin layers to be buried in the synthetic resin layer and inserted in the wiring circuit, and a heat expansion and contraction restricting layer formed to be buried in the synthetic resin layer adjacent to the synthetic resin layer in which the thin-film resistor is formed to be buried, arranged along the thin-film resistor, and having a smaller linear expansion coefficient than a linear expansion coefficient of the adjacent synthetic resin layers.

What is claimed is: 
     
       1. A multilayer wiring base plate comprising:
 an insulating plate including a plurality of insulating synthetic resin layers; 
 a wiring circuit provided in the insulating plate; 
 a thin-film resistor formed along one of the synthetic resin layers to be buried in the synthetic resin layers and inserted in the wiring circuit; and 
 a heat expansion and contraction restricting layer formed to be buried in the synthetic resin layers adjacent to the one of the synthetic resin layers along which the thin-film resistor is formed, and having a smaller linear expansion coefficient than a linear expansion coefficient of the adjacent synthetic resin layers; 
 wherein the heat expansion and contraction restricting layer is arranged to be approximately parallel to the thin-film resistor and extends outward and beyond an arranging area of the thin-film resistor, and wherein the heat expansion and contraction restricting layer is made of a metal material and is electrically insulated from the wiring circuit; 
 wherein both ends of the thin-film resistor are electrically connected to connection electrodes as a pair connected to the wiring circuit, respectively, and the connection electrodes as a pair cover respective corresponding end portions and edges of the thin-film resistor; and 
 wherein the respective connection electrodes have on mutually opposed surfaces thereof step portions respectively receiving the corresponding end portions and edges of the thin-film resistor and are electrically and mechanically coupled with both the corresponding end portions and edges of the thin-film resistor by the opposed step portions. 
 
     
     
       2. The multilayer wiring base plate according to  claim 1 , wherein the heat expansion and contraction restricting layer is made of an equal metal material to a metal material constituting the wiring circuit. 
     
     
       3. The multilayer wiring base plate according to  claim 1 , wherein the pair of connection electrodes is supported by a conductive path constituting a part of the wiring circuit, and the conductive path extends in the synthetic resin layer in a thickness direction of the synthetic resin layer. 
     
     
       4. A probe card comprising:
 the multilayer wiring base plate according to  claim 1 ; and 
 a plurality of probes projecting from a surface of the multilayer wiring base plate. 
 
     
     
       5. A multilayer wiring base plate comprising:
 an insulating plate including a plurality of insulating synthetic resin layers; 
 a wiring circuit provided in the insulating plate; 
 a thin-film resistor formed along one of the synthetic resin layers to be buried in the synthetic resin layers and inserted in the wiring circuit, wherein both ends of the thin-film resistor are electrically connected to respective connection electrodes, the connection electrodes connected to the wiring circuit, and wherein each connection electrode comprises a step portion that receives and covers an end edge of the thin-film resistor; and 
 a heat expansion and contraction restricting layer formed to be buried in the synthetic resin layers adjacent to the one of the synthetic resin layers along which the thin-film resistor is formed, and having a smaller linear expansion coefficient than a linear expansion coefficient of the adjacent synthetic resin layers.