Crackstop with embedded passive radio frequency noise suppressor and method

Abstract

Disclosed is a radio frequency integrated circuit (RFIC) chip that includes an integrated circuit (IC) area and a crackstop laterally surrounding the IC area. The crackstop includes a metallic barrier (or, alternatively, concentric metallic barriers) electrically isolated from the IC area. One or more noise suppressors and, particularly, one or more passive filters (e.g., low pass filter(s), high pass filter(s), band pass filter(s), and/or band stop filter(s)) are integrated into the structure of the metallic barrier(s) to inhibit propagation, through the crackstop, of noise signals within a specific RF range. The specific RF range can be a customer-specified operating parameter. By embedding customized noise suppressor(s) into the crackstop, local signal interference unique to the customer-specified operating parameters can be minimized while also avoiding or at least minimizing the risk of moisture ingress to the IC area. Also disclosed is a method of forming the chip.

What is claimed is: 
     
         1 . A method comprising:
 forming an integrated circuit area on a substrate, wherein the integrated circuit area includes radio frequency devices; and   forming, on the substrate, at least one metallic barrier laterally surrounding and physically separated from the integrated circuit area, wherein the at least one metallic barrier includes at least one passive filter that inhibits signal propagation through the at least one metallic barrier of radio frequency noise emitted by at least one of the radio frequency devices.   
     
     
         2 . The method of  claim 1 , further comprising:
 accessing a design for a chip, wherein the chip includes: the substrate having a center portion and an edge portion laterally surrounding the center portion; and the integrated circuit area is on the center portion;   establishing a specific radio frequency range for operation of the radio frequency devices;   updating the design to include, on the edge portion, the at least one metallic barrier and, integrated into the at least one metallic barrier, the at least one passive filter such that the at least one passive filter inhibits radio frequency noise signal propagation within the specific radio frequency range through the at least one metallic barrier; and   manufacturing the chip according to the updated design.   
     
     
         3 . The method of  claim 1 , wherein the passive filter is any of a low pass filter, a high pass filter, a band pass filter, and a band stop filter. 
     
     
         4 . The method of  claim 1 , wherein the at least one electromagnetic device is any of a resistor, a capacitor, an inductor, and a stub. 
     
     
         5 . The method of  claim 1 , wherein the at least one metallic barrier is a single continuous metallic barrier. 
     
     
         6 . The method of  claim 1 ,
 wherein the at least one metallic barrier includes: a first metallic barrier laterally surrounding and physically separated from the integrated circuit area and a second metallic barrier laterally surrounding the first metallic barrier, and   wherein at least the second metallic barrier is a continuous metallic barrier.   
     
     
         7 . A method comprising:
 forming, on a substrate, an integrated circuit area including radio frequency devices and non-radio frequency devices, wherein the radio frequency devices have a specific radio frequency range for operation; and   forming, on the substrate, at least one metallic barrier laterally surrounding and physically separated from the integrated circuit area and including at least one passive filter including at least one electromagnetic device, wherein the at least one passive filter inhibits radio frequency noise signal propagation within the specific radio frequency range through the at least one metallic barrier between a first device at a first location within the integrated circuit area and a second device at a second location within the integrated circuit area.   
     
     
         8 . The method of  claim 7 , wherein the first device is one of the radio frequency devices, and the second device is any of one of the radio frequency devices and one of the non-radio frequency devices. 
     
     
         9 . The method of  claim 7 , wherein the passive filter is any of a low pass filter, a high pass filter, a band pass filter, and a band stop filter. 
     
     
         10 . The method of  claim 7 , wherein the at least one electromagnetic device is any of a resistor, a capacitor, an inductor, and a stub. 
     
     
         11 . The method of  claim 7 , wherein the at least one metallic barrier is a single continuous metallic barrier. 
     
     
         12 . The method of  claim 7 ,
 wherein the at least one metallic barrier includes: a first metallic barrier laterally surrounding and physically separated from the integrated circuit area and a second metallic barrier laterally surrounding the first metallic barrier, and   wherein at least the second metallic barrier is a continuous metallic barrier.   
     
     
         13 . A method comprising:
 forming an integrated circuit area on a substrate; and   forming multiple metallic barriers on the substrate, wherein the multiple metallic barriers include:
 a first metallic barrier laterally surrounding and physically separated from the integrated circuit area; 
 a second metallic barrier laterally surrounding the first metallic barrier; and 
 a passive filter including at least one electromagnetic device, 
   wherein the passive filter is any of embedded in the first metallic barrier, embedded in the second metallic barrier, embedded in both the first metallic barrier and the second metallic barrier, and embedded in a space between the first metallic barrier and the second metallic barrier,   wherein the passive filter inhibits radio frequency noise signal propagation through the metallic barriers between different locations in the integrated circuit area,   wherein the first metallic barrier is on a first well region in the substrate,   wherein the second metallic barrier is on a second well region in the substrate, and   wherein the first well region and the second well region have different conductivity types.   
     
     
         14 . The method of  claim 13 , further comprising:
 accessing a design for a chip including: the substrate having a center portion and an edge portion laterally surrounding the center portion; and the integrated circuit area on the center portion and including radio frequency devices;   establishing a specific radio frequency range for operation of the radio frequency devices;   updating the design to include, on the edge portion, the metallic barriers and, integrated into the metallic barriers, the passive filter such that the passive filter is configured to inhibit signal propagation of radio frequency noise within the specific radio frequency range through the metallic barriers; and   manufacturing the chip according to the updated design.   
     
     
         15 . The method of  claim 13 ,
 wherein the integrated circuit area includes radio frequency devices cooperating within a specific radio frequency range,   wherein the radio frequency noise signal propagation inhibited by the passive filter is within the specific radio frequency range, and   wherein, when a radio frequency signal in the specific radio frequency range is emitted by a first device at a first location within the integrated circuit area and couples with the first metallic barrier, the passive filter inhibits transmission of the radio frequency signal through any of the first metallic barrier and the second metallic barrier to prevent interference with operation of a second device at a second location within the integrated circuit area.   
     
     
         16 . The method of  claim 15 , wherein the integrated circuit area further includes non-radio frequency devices, wherein the first device is one of the radio frequency devices and the second device is any of one of the radio frequency devices and one of the non-radio frequency devices. 
     
     
         17 . The method of  claim 13 ,
 wherein the substrate is a semiconductor substrate and includes: a first well region with a first-type conductivity; and a second well region physically separated from the first well region and having a second-type conductivity,   wherein an area of the substrate between the first well region and second well region has the first-type conductivity at a lower conductivity level than the first well region,   wherein the first metallic barrier is on the area of the substrate between the first well region and the second well region, and   wherein the second metallic barrier is on the second well region.   
     
     
         18 . The method of  claim 13 ,
 wherein the passive filter is any of a low pass filter, a high pass filter, a band pass filter, and a band stop filter, and   wherein the at least one electromagnetic device is any of a resistor, a capacitor, an inductor, and a stub.   
     
     
         19 . The method of  claim 13 , wherein the second metallic barrier is electrically isolated from the first metallic barrier and the at least one electromagnetic device is integrated into the first metallic barrier. 
     
     
         20 . The method of  claim 13 ,
 wherein the at least one electromagnetic device is an inductor, and   wherein the inductor is embedded in any of the first metallic barrier, the second metallic barrier, and a space between the first metallic barrier and the second metallic barrier.