Method and apparatus for de-embedding

Abstract

De-embedding apparatus and methods of de-embedding are disclosed. A de-embedding apparatus includes a test structure including a device-under-test (DUT) embedded in the test structure, and a plurality of dummy test structures including an open dummy structure, a distributed open dummy structure, and a short dummy structure. The distributed open dummy structure may include a first signal transmission line coupled to a left signal test pad and a second signal transmission line coupled to a right signal test pad, the first and second signal transmission lines having a smaller total length than a total length of signal transmission lines of the open dummy structure, and intrinsic transmission characteristics of the DUT can be derived from transmission parameters of the dummy test structures and the test structure

What is claimed is: 
     
         1 . An apparatus, comprising:
 a test structure including a device-under-test (DUT) embedded in the test structure; and   a plurality of dummy test structures including an open dummy structure, a distributed open dummy structure, and a short dummy structure,   wherein the distributed open dummy structure includes two signal test pads and no signal transmission line therebetween, and   wherein intrinsic transmission characteristics of the DUT can be derived from transmission parameters of the dummy test structures and the test structure.   
     
     
         2 . The apparatus of  claim 1 , wherein the distributed open dummy structure includes a plurality of ground lines running in parallel, each ground line disposed between two ground test pads, and the signal test pads and the ground test pads forming a ground-signal-ground configuration. 
     
     
         3 . The apparatus of  claim 2 , wherein each of the plurality of ground lines of the distributed open dummy structure includes a plurality of vias between a plurality of vertically-stacked conductive layers. 
     
     
         4 . The apparatus of  claim 2 , wherein each of the open and short dummy structures includes a plurality of secondary ground lines running perpendicular to ground lines disposed between two ground test pads, and wherein the distributed open dummy structure does not include a plurality of secondary ground lines running perpendicular to the ground lines between the two ground test pads. 
     
     
         5 . The apparatus of  claim 1 , further comprising:
 a second distributed open dummy structure including a first signal transmission line coupled to a left signal test pad and a second signal transmission line coupled to a right signal test pad, the first and second signal transmission lines having a smaller total length than a total length of corresponding signal transmission lines of the open dummy structure,   wherein intrinsic transmission characteristics of the DUT can be derived from transmission parameters of the open dummy structure, the distributed open dummy structure, the second distributed open dummy structure, and the test structure.   
     
     
         6 . The apparatus of  claim 1 , wherein the DUT of the test structure is coupled to a left signal pad by a third signal transmission line and to a right signal pad by a fourth signal transmission line. 
     
     
         7 . The apparatus of  claim 1 , wherein the open dummy structure includes a first signal transmission line coupled to a left signal test pad, a second signal transmission line coupled to a right signal test pad, and a plurality of ground lines running in parallel with each ground line disposed between two ground test pads, wherein the signal test pads and the ground test pads of the open dummy structure form a ground-signal-ground configuration. 
     
     
         8 . An apparatus, comprising:
 a test structure including a device-under-test (DUT) embedded in the test structure; and   a plurality of dummy test structures including an open dummy structure, a distributed open dummy structure, and a short dummy structure,   wherein the distributed open dummy structure includes a first signal transmission line coupled to a left signal test pad and a second signal transmission line coupled to a right signal test pad, the first and second signal transmission lines having a smaller total length than a total length of signal transmission lines of the open dummy structure, and   wherein intrinsic transmission characteristics of the DUT can be derived from transmission parameters of the dummy test structures and the test structure.   
     
     
         9 . The apparatus of  claim 8 , wherein each of the first and second signal transmission lines of the distributed open dummy structure includes a plurality of vias between a plurality of vertically-stacked conductive layers. 
     
     
         10 . The apparatus of  claim 8 , wherein the distributed open dummy structure further includes a plurality of ground lines running in parallel to the first and second signal transmission lines, each ground line disposed between two ground test pads, wherein the signal test pads and the ground test pads of the distributed open dummy structure form a ground-signal-ground configuration. 
     
     
         11 . The apparatus of  claim 10 , wherein each of the plurality of ground lines of the distributed open dummy structure includes a plurality of vias between a plurality of vertically-stacked conductive layers. 
     
     
         12 . The apparatus of  claim 10 , wherein each of the open and short dummy structures includes a plurality of secondary ground lines running perpendicular to ground lines disposed between two ground test pads, and wherein the distributed open dummy structure does not include a plurality of secondary ground lines running perpendicular to the ground lines between the two ground test pads. 
     
     
         13 . The apparatus of  claim 8 , further comprising:
 a second distributed open dummy structure including two signal test pads and no signal transmission line therebetween,   wherein intrinsic transmission characteristics of the DUT can be derived from transmission parameters of the open dummy structure, the distributed open dummy structure, the second distributed open dummy structure, and the test structure.   
     
     
         14 . The apparatus of  claim 8 , wherein the DUT of the test structure is coupled to a left signal pad by a third signal transmission line and to a right signal pad by a fourth signal transmission line. 
     
     
         15 . The apparatus of  claim 8 , wherein the open dummy structure includes a first signal transmission line coupled to a left signal test pad, a second signal transmission line coupled to a right signal test pad, and a plurality of ground lines running in parallel with each ground line disposed between two ground test pads, wherein the signal test pads and the ground test pads of the open dummy structure form a ground-signal-ground configuration. 
     
     
         16 . A method of de-embedding, comprising:
 forming a test structure including a device-under-test (DUT) coupled to a left signal pad by a first transmission line and a right signal pad by a second transmission line;   forming a plurality of dummy test structures including an open dummy structure, a distributed open dummy structure, and a short dummy structure,
 wherein the open dummy structure includes a third signal transmission line coupled to a left signal test pad and a fourth signal transmission line coupled to a right signal test pad, 
 wherein the distributed open dummy structure includes a fifth signal transmission line coupled to a left signal test pad and a sixth signal transmission line coupled to a right signal test pad, the fifth and sixth signal transmission lines having a smaller total length than a total length of the third and fourth signal transmission lines of the open dummy structure; 
   measuring transmission parameters of the test structure and the plurality of dummy test structures; and   determining intrinsic transmission characteristics of the DUT using the transmission parameters of the test structure and the plurality of dummy test structures.   
     
     
         17 . The method of  claim 16 , wherein each of the open dummy structure, the distributed open dummy structure, and the short dummy structure is formed to include a plurality of ground lines running in parallel to signal transmission lines, each ground line disposed between two ground test pads, and the signal test pads and the ground test pads of each dummy structure forming a ground-signal-ground configuration. 
     
     
         18 . The method of  claim 16 , wherein each of the open and short dummy structures is formed to include a plurality of secondary ground lines running perpendicular to ground lines disposed between two ground test pads, and wherein the distributed open dummy structure is formed to not include a plurality of secondary ground lines running perpendicular to the ground lines between the two ground test pads. 
     
     
         19 . The method of  claim 16 , further comprising:
 forming a plurality of dummy test structures including a second distributed open dummy structure having two signal test pads and no signal transmission line therebetween; and   determining intrinsic transmission characteristics of the DUT from transmission parameters of the open dummy structure, the distributed open dummy structure, the second distributed open dummy structure, and the test structure.   
     
     
         20 . The method of  claim 16 , wherein the intrinsic transmission characteristics of the DUT are determined using an open-short de-embedding technique or an open-short-through de-embedding technique.