Methods related to packaged modules having tuned shielding

Abstract

Disclosed are devices and methods related to radio-frequency (RF) shielding of RF modules. In some embodiments, tuned shielding can be achieved by utilizing different structures and/or arrangements of shielding-wirebonds to increase shielding in areas where needed, and to decrease shielding where not needed. Such tuning of shielding requirements can be obtained by measuring RF power levels at different locations of a module having a given design. Such tuned RF shielding configurations can improve the overall effectiveness of shielding, and can also be more cost effective to implement.

What is claimed is: 
     
         1 . A method for fabricating a radio-frequency (RF) module, the method comprising:
 providing a packaging substrate configured to receive a plurality of components;   mounting one or more RF components on the packaging substrate; and   forming an RF shield relative to the one or more RF components, the RF shield including a first segment configured to provide a base-level of shielding, and a second segment configured to provide a selective-level of shielding that is different than the base-level based on an RF emission pattern associated with operation of the RF module.   
     
     
         2 . The method of  claim 1  wherein the RF shield includes a plurality of wirebonds that are electrically connected to a ground plane on or within the packaging substrate. 
     
     
         3 . The method of  claim 2  wherein the second segment providing the selective-level of shielding is configured based on an emission hotspot in the RF emission pattern. 
     
     
         4 . The method of  claim 3  wherein the selective-level of shielding is enhanced when compared to the base-level of shielding. 
     
     
         5 . The method of  claim 4  wherein the second segment is positioned to provide the enhanced selective-level of shielding of the emission hotspot for a location within the RF module or external to the RF module. 
     
     
         6 . The method of  claim 3  wherein the selective-level of shielding is reduced when compared to the base-level of shielding. 
     
     
         7 . The method of  claim 6  wherein the second segment is positioned at a location where the reduced selective-level of shielding does not have a significant impact from the emission hotspot. 
     
     
         8 . The method of  claim 2  further comprising forming an overmold over the packaging substrate to substantially encapsulate the plurality of RF components and the wirebonds of the RF shield. 
     
     
         9 . The method of  claim 8  further comprising forming a conductive layer over the overmold such that the wirebonds of the RF shield provide an electrical connection between the conductive layer and the ground plane. 
     
     
         10 . The method of  claim 2  wherein each of the plurality of wirebonds has two ends attached to the packaging substrate, or one end attached to the packaging substrate. 
     
     
         11 . A method for shielding a radio-frequency (RF) module, the method comprising:
 determining a shielding location for a tuned RF shield within the RF module such that presence of the tuned RF shield at the shielding location selectively reduces an impact of a hotspot in an RF emission pattern relative to the RF module; and   implementing one or more wirebonds to yield the tuned RF shield at the shielding location.   
     
     
         12 . The method of  claim 11  wherein the hotspot is located within the RF module. 
     
     
         13 . The method of  claim 12  wherein the impact of the hotspot is selectively reduced at another location within the RF module or external to the RF module. 
     
     
         14 . The method of  claim 13  wherein the hotspot is based on a radiated power level at or near the location within the RF module. 
     
     
         15 . The method of  claim 14  further comprising determining the location of the hotspot prior to the determining of the shielding location. 
     
     
         16 . The method of  claim 12  wherein the one or more wirebonds are configured to provide the selective reduction in the impact of the hotspot sufficiently without unnecessary wirebonds. 
     
     
         17 . The method of  claim 16  wherein the tuned RF shield is an independent RF shield. 
     
     
         18 . The method of  claim 16  wherein the tuned RF shield includes a modification to an existing RF shield. 
     
     
         19 . The method of  claim 18  wherein the modification includes an increased number of wirebonds at or near the shielding location. 
     
     
         20 . The method of  claim 18  wherein the modification includes a decreased number of wirebonds at or near a location away from the shielding location.