High-speed, flexible integrated circuits and methods for making high-speed, flexible integrated circuits

Abstract

The present invention provides flexible devices, such as integrated circuits, having a multilevel electronic device structure including two or more electronic components. The electronic components within the structure are electrically connected by an interconnect structure having multiple interconnect levels. In addition to the multilevel electronic device structure, the flexible devices include an elastomeric material disposed around the interconnect levels, including within the spaces between the interconnect levels.

What is claimed is: 
     
         1 . A flexible device comprising:
 (a) a multilevel electronic device structure comprising at least two electronic components electrically connected by an electrical interconnect structure having multiple interconnect levels along the vertical axis of the device; and   (b) an elastomeric dielectric material disposed around the electrical interconnect structure, including within spaces between the interconnect levels.   
     
     
         2 . The flexible device of  claim 1 , wherein the flexible device has a thickness of no greater than about 50 μm and can be formed into a rolled structure with a convex bending radius of 20 mm or less and still perform its intended functions. 
     
     
         3 . The flexible device of  claim 1 , wherein the electronic components and the electrical interconnect structure are encased in the elastomeric dielectric material. 
     
     
         4 . The flexible device of  claim 1 , wherein the flexible device is substantially free of inorganic dielectric material between interconnect levels, other that inorganic dielectric materials that form part of a device active region. 
     
     
         5 . The flexible device of  claim 1 , wherein the electrical interconnect structure has a least four interconnect levels. 
     
     
         6 . The flexible device of  claim 1 , wherein the elastomeric dielectric material comprises PDMS. 
     
     
         7 . The flexible device of  claim 1  comprising an integrated circuit having at least two transistors electrically connected by the electrical interconnect structure. 
     
     
         8 . The flexible device of  claim 7 , wherein at least one of the at least two transistors is a heterojunction bipolar transistor. 
     
     
         9 . The flexible device of  claim 8 , wherein the integrated circuit comprises a power amplifier. 
     
     
         10 . The flexible device of  claim 9 , wherein the power amplifier comprises SiGe heterojunction bipolar transistors having maximum oscillation frequencies of at least 40 GHz, the power amplifier having a power gain of at least 14 dB at 24 GHz. 
     
     
         11 . A method for fabricating a flexible device from a rigid device comprising: a multilevel electronic device structure comprising at least two electronic components electrically connected by an electrical interconnect structure having multiple interconnect levels along the vertical axis of the device; and a rigid dielectric material disposed around the electrical interconnect structure, including within spaces between the interconnect levels, the method comprising:
 (a) removing the rigid dielectric material to expose the electrical interconnect structure;   (b) backfilling the resulting spaces between the interconnect levels with a liquid elastomeric dielectric precursor; and   (c) curing the liquid elastomeric dielectric precursor to form an elastomeric dielectric material between the interconnect levels.   
     
     
         12 . The method of  claim 11  further comprising coating a front side and a back side of the electronic device structure with a liquid elastomeric dielectric precursor, and curing the liquid elastomeric dielectric precursor to form an elastomeric material on the front side and the back side of the electronic device structure, such that the electronic components and the electrical interconnect structure are encased in elastomeric dielectric material. 
     
     
         13 . The method of  claim 11 , wherein removing the rigid dielectric material comprises etching the rigid dielectric material with an etchant that selectively removes the rigid dielectric material. 
     
     
         14 . The method of  claim 13 , wherein the rigid dielectric material comprises SiO 2 , SiN x  or a combination thereof and the etchant comprise HF. 
     
     
         15 . The method of  claim 13  further comprising protecting one or more device active regions prior to etching the rigid dielectric material. 
     
     
         16 . The method of  claim 11 , wherein the elastomeric dielectric material comprises PDMS. 
     
     
         17 . The method of  claim 11 , wherein the device comprising an integrated circuit having at least two transistors electrically connected by the electrical interconnect structure.