Abstract:
An integrated package arrangement for an electronic system includes a photodetector module for incorporating a photodetector for use by the electronic system. An analog to digital converter (ADC) module is coupled to the photodetector module. The ADC module includes a plurality of ADC dies for use by an ADC of the electronic system.

Description:
PRIORITY INFORMATION  
       [0001]     This application claims priority from provisional application Ser. No. 60/808,194 filed May 24, 2006, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The invention is related generally to a wide array of sensor applications where the sensor needs to be in close proximity to the data acquisition electronics to minimize interconnect complexity, improve electrical performance and reduce system size and cost.  
         [0003]     This invention describes a specific application in the field of, for example, continuous time (CT) scanners, and in particular to a single package detector and digital converter integration, which can be used in a CT scanner.  
         [0004]     The CT scanner market is undergoing a revolution in system integration to enable faster machines in the medical market. These machines are capable of providing clear 3-D view of human body at a high patient throughput rate. At the core of these machines, design innovations are required to enable more efficient system performance, space savings and cost.  
         [0005]     Currently, the detectors and the associated converter electronics used in CT scanner are located in separate locations, which make it difficult to gain the performance and higher throughput advantages. There is a need in the art to combine the detector and associated converter electronics in a single package for effectively increase performance and higher throughput advantages.  
       SUMMARY OF THE INVENTION  
       [0006]     According to one aspect of the invention, there is provided an integrated package arrangement for an electronic system. The integrated package arrangement includes a An analog to digital converter (ADC) module is coupled to the photodetector module. The ADC module includes a plurality of ADC dies for use by an ADC of the electronic system.  
         [0007]     According to another aspect of the invention, there is provided a method of integrating a photodetector and an analog digital converter (ADC) of an electronic system. The method includes providing photodetector module for incorporating a photodetector for use by the electronic system. Also, the method includes coupling an analog to digital converter (ADC) module to the photodetector module. The ADC module includes a plurality of ADC dies for use by an ADC of the electronic system.  
         [0008]     According to another aspect of the invention, there is provided a method of forming an integrated package arrangement for an electronic system. The method includes a forming photodetector module for incorporating a photodetector for use by the electronic system. Also, the method includes forming an analog to digital converter (ADC) module being coupled to the photodetector module. The ADC module includes a plurality of ADC dies for use by an ADC of the electronic system. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a schematic diagram illustrating a package arrangement integrating a photodetector and an analog to digital converter (ADC) dies of a CT scanner;  
         [0010]      FIG. 2  is a schematic diagram illustrating a package arrangement having substantially similar components as the package element of  FIG. 1  except a photodetector is removed;  
         [0011]      FIG. 3  is a schematic diagram illustrating a package arrangement having no laminate substrate; and  
         [0012]      FIG. 4  is schematic diagram illustrating a package arrangement having ADC dies mounted on the top side of a laminate. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]     The invention provides a solution enabling efficient usage of system space which in turn helps to provide enhanced system detection capability, more patient scanning per unit time and overall lower system cost for electronic systems, such as a CT scanner. The invention also aids in designing flexible, scaleable detector modules which can be used for varying electronic system configurations, such as other medical electronics, digital cameras, IR imagers, laboratory instruments, photodiodes, or the like.  
         [0014]      FIG. 1  shows a package arrangement  2  integrating a photodetector  11  and an analog to digital converter (ADC) dies  16  of a CT scanner. The package arrangement  2  includes a photodetector  11  having solder balls  10  for coupling on a laminate substrate  8  with multiple ADC dies  16 . The photodetector  11  includes a photodiode junction  5  on the top scintillator side and photodetector dies  6 . Vias  4  are used for coupling the photodiode junctions  5  to solder balls  10 . The solder balls  10  are encapsulated using organic material on the laminate substrate  8 . An underfill  12  encapsulates the solder balls  10  and the region between the photodetector dies  6  and laminate substrate  8 . This allows for overhang of the photodetector dies  6  to meet at least a 160 μm spacing used in other customer boards. The photodetectors dies  6  are designed to be longer then the laminate substrate  8  and the underfill  12  includes a region that is slightly larger lengthwise then the laminate substrate  12 . This permits overhanging of the photodector dies  6 .  
         [0015]     The ADC dies  16  are plastic molded on the opposite side of the laminate substrate  8 . On the same side, solder balls  14  are provided so as to allow a PC board to be coupled to the package arrangement  2 . In other embodiments, ceramic interposers can be provided in place of the laminate substrate  8 . Also, multiple ADC dies can be provided for one BGA package.  
         [0016]     The package arrangement  2  can also be applied in other electronic systems such as medical electronics, digital cameras, IR imagers, laboratory instruments, photodiodes, or the like.  
         [0017]     However, the invention permits other types of photodetector modules to be used beside the one described in  FIG. 1 .  FIG. 2  shows a package arrangement  20  having substantially similar components as the package element  2  of  FIG. 1  except the photodetector is removed. This allows a user to attach their preferred photodetector on the topside of a laminate substrate  22 . The package arrangement  20  includes the laminate substrate  22 , ADC plastic molded dies  26 , and the solder balls  30  to couple to a PC board, which is similarly arranged as package arrangement  2 .  
         [0018]     The package arrangement  22  can also be applied in other electronic systems such as medical electronics, digital cameras, IR imagers, laboratory instruments, photodiodes, or the like.  
         [0019]      FIG. 3  shows a package arrangement  40  having no laminate substrate. A multiple bump ADC dies flip chip  46  is mounted directly on the underside of a photodetector die  44 . The bottom side of the photo detector die  44  is metal patterned to interconnect the ADC dies  46  to the photo detector die  44 . Vias  42  are used for coupling the photodiode to it&#39;s bottom side. The photodetector die  44  can sit directly on a system PC board using solder balls  48 . The package arrangement  40  can also be applied in other electronic systems such as medical electronics, digital cameras, IR imagers, laboratory instruments, photodiodes, or the like.  
         [0020]      FIG. 4  shows a package arrangement  66  integrating a photodetector  82  and an analog to digital (ADC) converter dies  76  of a CT scanner. The package arrangement  66  includes a photodetector  82  having solder balls  70  for coupling on a laminate substrate  72  with multiple bumped flip chip ADC dies  76 . The photodetector  82  includes photodiode junctions  80  on the top scintillator side and photodetector dies  68 . Vias  78  are used for coupling the photodiode junctions  80  to solder balls  70 .  
         [0021]     The ADC dies  76  is on the front side of the laminate substrate  72 . On the other side, solder balls  74  are provided so as to allow a PC board to be coupled to the package arrangement  66 . In other embodiments, ceramic interposers can be provided in place of the laminate substrate  72 . Also, multiple ADC dies can be provided for one BGA package. The package arrangement  66  can also be applied in other electronic systems such as medical electronics, digital cameras, IR imagers, laboratory instruments, photodiodes, or the like.  
         [0022]     Although the present invention has been shown and described with respect to several preferred embodiments thereof, various changes, omissions and additions to the form and detail thereof, may be made therein, without departing from the spirit and scope of the invention.