Patent Publication Number: US-2011062571-A1

Title: Optical device, integrated circuit device and system

Description:
BACKGROUND 
     1. Technical Field 
     The present invention relates to the field of integrated circuit devices or packages and integrated circuit systems. 
     2. Description of the Related Art 
     A known integrated circuit system comprises a mounting plate, an integrated circuit die having an optical area mounting on the mounting plate and an annular support mounting on the mounting plate around the die and provided with an optical lens placed in front of the optical area. 
     BRIEF SUMMARY 
     It is proposed an optical device for an integrated circuit device, which can include a laminated substrate having a through-passage and a tubular frame in which an optical lens is mounted, the tubular frame having an end part inserted or integrated in the through-passage of the laminated substrate. 
     The tubular frame can comprise a peripheral shoulder inserted or integrated in the laminated substrate. 
     The laminated substrate can comprise a core layer having a through-passage receiving the peripheral shoulder of the tubular frame and at least a side layer placed above a side of the core layer. 
     The laminated substrate can comprise a core layer having a through-passage receiving the peripheral shoulder of the tubular frame and side layers placed on each side of the core layer. 
     The laminated substrate can include an electrical connection network. 
     It is proposed an integrated circuit device, which can include an optical device and an integrated circuit die carried by the laminated substrate and having an active optical area placed in front of the optical lens. 
     The device can comprise an encapsulated means for encapsulating the integrated circuit die on a face of the substrate. 
     It is proposed an integrated circuit system, which can include an integrated circuit device and a mounting plate on which the integrated circuit device is mounted by means of connection balls placed between the laminated substrate and the mounting plate, the mounting plate having a through-passage through which the tubular frame extends. 
     It is proposed an integrated circuit system, which can include a mounting plate on which the integrated circuit device is mounted by means of connection balls placed between the laminated substrate and the mounting plate, the frame being placed at the opposite side of the mounting plate. 
     It is proposed a process for manufacturing an optical device comprising a tubular frame and an optical lens, which can include making an annular groove inside the tubular frame, heating the tubular frame for obtaining a radial dilatation thereof, placing the optical lens in the tubular frame in a position in which the peripheral edge of the lens is in front of the groove while the tubular frame is dilated and cooling the tubular frame for obtaining a radial retraction thereof permitting the peripheral edge of the optical lens to be insert in the annular groove. The process can also include introducing an end peripheral shoulder of the tubular frame in a cavity of a core layer of a substrate having a build-up layer on a face of the core layer and extending on a face of the peripheral shoulder, and placing a die on the substrate, this die having an optical area in front of the optical lens. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Other advantages and features will become apparent by studying integrated circuit systems, described by way of non-limited examples and illustrated by the appended drawings in which: 
         FIG. 1  represents a cross section of an integrated circuit system; 
         FIG. 2  represents a cross section of another integrated circuit system; 
         FIG. 3  represents a cross section of an intermediate step of fabrication of an optical device of  FIG. 1 ; 
         FIG. 4  represents a cross section of another intermediate step of fabrication of an optical device of  FIG. 1 ; 
         FIG. 5  represents a cross section of an intermediate step of fabrication of an integrated circuit device of  FIG. 1 ; 
         FIG. 6  represents a cross section of another intermediate step of fabrication of an integrated circuit device of  FIG. 1 ; and 
         FIG. 7  represents a cross section of another intermediate step of fabrication of an integrated circuit device of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , it can be seen that an integrated circuit system  1  is represented, comprising an optical integrated circuit device or package  2  and a connection mounting plate  3 . 
     The integrated circuit package  2  includes an optical device  4  comprising a laminated substrate  5  and a tubular frame  6  placed perpendicularly to the laminated substrate  5  and supporting an optical lens  7  in its passage  6   a.    
     The laminated substrate  5  comprises a dielectric core layer  8  having a through-passage  9 . 
     The tubular frame  6  is provided with a peripheral end shoulder  10  which is inserted in the passage  9 . 
     The laminated substrate  5  comprises a first dielectric build-up layer  11  placed above a side of the core layer  8  and above the radial end of the tubular frame adjacent to the shoulder  10 , this first build-up layer  11  having a through-passage  12  corresponding to the passage  6   a  of the frame  6 . 
     The thickness of the shoulder  10  can be substantially equal to the thickness of the core layer  8 . 
     The laminated substrate  5  comprises also a second dielectric build-up layer  13  placed above another side of the core layer  8  and the other side of the shoulder  10 , this second build-up layer  11  having a through-passage  14  traversed by the tubular frame  6 . 
     The laminated substrate  5  includes an electrical connection network  15  which comprises a connection pattern  16  formed on the external face of the build-up layer  11 , a connection pattern  17  formed between the core layer  8  and the build-up layer  11 , a connection pattern  18  formed between the core layer  8  and the build-up layer  13 , and an external connection pattern  19  formed on the external face of the build-up layer  13 . 
     The electrical connection network  15  comprises further electrical vias  20  crossing the build-up layer  11  for connecting the connection pattern  16  and the connection pattern  17 , electrical vias  21  crossing passages  21   a  of the core layer  8  for connecting the connection pattern  17  and the connection pattern  18 , and electrical vias  22  crossing the build-up layer  13  for connecting the connection pattern  18  and the connection pattern  19 . 
     The integrated circuit package  2  includes further an integrated circuit die  23 , opposite to the tubular frame  6  and mounted by intermediate electrical connection balls  24  located between connection points of a face of the die  23  and the connection pattern  16 . The integrated circuit die  23  includes an active optical area  25  placed in correspondence to the passage  6   a  of the tubular frame  6  and in consequence in front of the optical lens  7 . 
     The integrated circuit package  2  includes also an encapsulating block  26  which encapsulates the die  23  and the connection balls  24  above the external face of the side layer  11 . 
     As an example, the package  2  can be manufactured according to the following steps. 
     For fabricating the tubular frame  6  provided with the lens  7 , a groove  6   b  is made inner a metal tubular frame ( FIG. 3 ). This frame  6  is heated for obtaining a radial dilatation thereof and an optical lens  7  is placed in the tubular frame in a position in which the peripheral edge of the lens  7  is in front of the groove while the tubular frame is dilated ( FIG. 4 ). After this, the tubular frame is cooled for obtaining a radial retraction thereof permitting the peripheral edge of the lens  7  to be inserted in the annular groove  6   b.    
     Having a core layer plate, through-holes  21   a  are realized and metal vias  21  are realized. Metal layers are formed on the sides of the core layer plate and are etching for obtaining connection patterns  17  and  18 . Having a side build-up layer  13  providing with a metal connection pattern  19  and metal vias  22 , this side layer  13  is linked to the corresponding side of the core layer plate. After this, a hole  9  is realized through the core layer plate and a hole  14  is realized through the side layer  13 . 
     The structure obtained at the end of the above step is illustrated on  FIG. 5 . 
     After this, the tubular frame  6  is introduced through the holes  9  and  14  up to insert the shoulder  10  thereof in the hole  9  of the core layer  8 , eventually with interposition of glue, in contact with the side layer. 
     The structure obtained at the end of the above step is illustrated on  FIG. 6 . 
     After this, a side build-up layer  11  with a metal connection pattern  16  and metal vias  20  is formed on the corresponding side of the core layer  8 , this side build-up layer  11  having the through-hole  12 . 
     An optical device  4  obtained at the end of the above step is illustrated on  FIG. 7 . 
     Consequently, the end part of the tubular frame  6  is inserted in the laminated substrate  5 , by the means of the peripheral shoulder  10  integrated in the through-hole  9  of the core layer  8  and between the side layers  11  and  13 , around the through-holes  12  and  14  thereof, of the laminated substrate  5 . 
     After this, an integrated circuit die  23  is attached by means of connection solder balls  24 , in a position in which the sensitive optical area  24  is turned towards the lens  7 , and an encapsulated block  26  is formed for example by molding. 
     At the end of the above step, an integrated circuit package  2  is realized. 
     As illustrated on  FIG. 1 , the integrated circuit package  2  as above described can be carried by the connection mounting plate  3  by the intermediate of electrical connection solder balls  27  located between the connection pattern  19  and a printed-circuit pattern  28  formed on a face  29  of the mounting plate  3 , the tubular frame  6  being engaged freely through a through-passage  30  of the mounting plate  3  and the die  23  being opposite to the mounting plate  3  with respect to the laminated substrate  5 . 
     Referring now to  FIG. 2 , as another example, it can be seen that an integrated circuit system  31  is represented, comprising an integrated circuit device or package  32  including an optical device  33 . 
     The optical device  33  differs from the optical device  4  by the fact that it includes a different laminated substrate  34 . 
     The laminated substrate  34  comprises a dielectric core layer  35  having a through-passage  36 , a side dielectric build-up layer  37  having a through-passage  38 , corresponding to the build-up layer  11 , and a simple dielectric layer  39  replacing the build-up layer  13  and having a through-passage  39   a.    
     The laminated substrate  34  includes a metal electrical connection network  40  which comprises a connection pattern  41  formed between the core layer  35  and the build-up layer  37 , a connection pattern  42  formed on the external side of the build-up layer  37  and vias  43  through the build-up layer  37  for connecting the connection pattern  41  and the connection pattern  42 . A metal layer  44  is provided between the core layer  35  and the simple layer  39 . 
     As in the previous example, a tubular frame  44  provided with an optical lens  45  extends perpendicularly to the laminated substrate  34  and has an end peripheral shoulder  46  which is integrated in the through-passage  36  of the core layer  35  and between the build-up layer  37  and the simple layer  39 , this frame extending through the through-passage  39   a  of the simple layer  39 . 
     The integrated circuit package  32  includes further an integrated circuit die  47 , opposite to the tubular frame  44  and mounted by intermediate electrical connection balls  48  located between connection points of a face of the die  47  and certain points of the connection pattern  42 . The integrated circuit die  47  includes an active optical area  49  placed in correspondence to the through-passage  44   a  of the tubular frame  44  and in consequence in front of the optical lens  45 . 
     The integrated circuit package  32  includes also an encapsulating block  50  which encapsulates the die  47  and the connection solder balls  48  above the external face of the side build-up layer  37 . The encapsulating block  50  is such that a peripheral portion of the connection pattern  42  is not covered. 
     The integrated circuit package  32  can be fabricated substantially as the package  2  of the previous example. 
     The integrated circuit system  31  includes further a mounting plate  51  providing with a printed-circuit pattern  52  on a face  53 . 
     The integrated circuit package  32  is linked to the mounting plate  51  by the intermediate of connection solder balls  54  which are placed between the peripheral portion of the connection pattern  42  and the printed-circuit pattern  52 , the tubular frame  44  extending opposite to the mounting plate  51  with respect to the laminated substrate and further the integrated circuit die  47  and the mounting plate  51  being placed at the same side with respect to the laminated substrate  34 . 
     It results from the above description the following advantages. 
     The core layer  8  gives the principle resistance of the substrate  5 . 
     The fixing end part of the frame  6  and  11  having eventually the shoulder  10  is inserted or integrated in a cavity of the substrate  5  formed in the passage  9  of the core layer  8  and eventually between the side layers  11  and  13 . 
     Resulting from this integration, the frame  6  and the lens  7  carried thereby are perfectly positioned. 
     Although embodiments of the devices and systems of the present disclosure have been illustrated in the accompanying drawings and described in the foregoing detailed description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the spirit of the disclosure. 
     The various embodiments described above can be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.