Patent Publication Number: US-2022238502-A1

Title: Optical device package

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 16/664,652 filed Oct. 25, 2019, the contents of which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     The instant disclosure relates to an optical device package, and more particularly, to a package structure with a low manufacturing cost and a confidential performance. 
     2. Description of Related Art 
     An optical device package can include some semiconductor devices on a carrier. Some of the semiconductor devices can be integrated or embedded into the carrier for miniaturization. However, cost of integrating or embedding the semiconductor devices into the carrier may be inevitably increased. 
     SUMMARY 
     In some embodiments, an optical device package comprises a carrier and a lid. The carrier comprises a first surface and a second surface recessed with respect to the first surface. The lid is disposed on the second surface of the carrier. 
     In some embodiments, an optical device package comprises a carrier and a lid. The carrier comprises a first surface and a second surface. The lid comprises a first surface supported by the second surface of the carrier. The first surface of the carrier and the first surface of the lid are not lying in s same plane. 
     In some embodiments, a method of manufacturing an optical device package comprises: providing a carrier; removing a portion of the carrier such that the carrier has a first surface and a second surface recessed with respect to the first surface, and disposing a lid on the second surface of the carrier. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 2  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 3  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 4  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 5  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 6  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 7  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 8  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 9  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 10  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 11  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 12  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 13  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 14  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 15  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; 
         FIG. 16  illustrates a cross-sectional view of an optical device package in accordance with some embodiments of the present disclosure; and 
         FIGS. 17A, 17B, 17C, 17D, 17E, 17F, 17G, 17H, 17I and 17J  illustrate one or more stages of a method of manufacturing optical device packages in accordance with some embodiments of the present disclosure. 
         FIGS. 18A, 18B, 18C, 18D, 18E, 18F, 18G, 18H, 18I and 18J  illustrate one or more stages of a method of manufacturing optical device packages in accordance with some embodiments of the present disclosure. 
     
    
    
     Common reference numerals are used throughout the drawings and the detailed description to indicate the same or similar components. The present disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings. 
     DETAILED DESCRIPTION 
     The aforementioned illustrations and following detailed descriptions are by example for the purpose of further explaining the scope of the instant disclosure. Other objectives and advantages related to the instant disclosure will be illustrated in the subsequent descriptions and appended drawings. 
     Spatial descriptions, such as “above,” “below,” “up,” “left,” “right,” “down,” “top,” “bottom,” “vertical,” “horizontal,” “side,” “higher,” “lower,” “upper,” “over,” “under,” and so forth, are indicated with respect to the orientation shown in the figures unless otherwise specified. It should be understood that the spatial descriptions used herein are for purposes of illustration, and that practical implementations of the structures described herein can be spatially arranged in any orientation or manner, provided that the merits of embodiments of this disclosure are not deviated by such arrangement. 
       FIG. 1  illustrates a cross-sectional view of an optical device package  1  in accordance with some embodiments of the present disclosure. The optical device package  1  comprises a carrier  10  and a lid  17 . In some embodiments, the carrier  10  may include ceramic material or a metal plate. In some embodiments, the carrier  10  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  10  may include a plurality of traces. The carrier  10  illustrated in  FIG. 1  comprises a redistribution structure  11 , electrical connections  12 , an encapsulant  13 , a semiconductor device  14 , an optical element  15  and an under-fill layer  16 . 
     The redistribution structure  11  has a surface  111  and a surface  112  opposite the surface  111 . At least one of the electrical connections  12  is on the surface  112  of the redistribution structure  11 . The encapsulant  13  encapsulates the surface  112  and the side surface  113  of the redistribution structure  11  and the electrical connections  12 . A portion of each electrical connection  12  is exposed by the encapsulant  13 . 
     The semiconductor device  14  is mounted on the surface  112  of the redistribution structure  11 . The semiconductor device  14  and the redistribution structure  11  are electrically connected by the bumps  141 . In some embodiments, the space between the bumps  141  is filled with an under-fill layer  16 . The electrical connections  12  surround a periphery of the semiconductor device  14  and are used to fan-out the inputs and outputs of the semiconductor device  14 . The optical element  15  (e.g., optical emitter or optical detector) is mounted on and electrically connected to the surface  111  of the redistribution structure  11 . 
     As shown in  FIG. 1 , the encapsulant  13  encapsulates the surface  112  and the side surface  113  of the redistribution structure  11  and the electrical connections  12 . The encapsulant  13  has a surface  131 , a surface  132  recessed with respect to the surface  131  and a surface  135  connecting the surface  131  and  132 . The surface  131  of the encapsulant  13  may be substantially coplanar with the surface  111  of the redistribution structure  11 , and thus the surface  132  of the encapsulant  13  is elevationally less than the surface  131  of the encapsulant  13  and the surface  111  of the redistribution structure  11 . In addition, the surface  132  is adjacent to the side surface  133  of the encapsulant  13 . 
     Given the above, referring to  FIG. 1 , the carrier  10  has a recessed portion at its side, which is formed by the surfaces  132  and  135 . 
     Further, a lid  17  is arranged on the carrier  10 . Referring to  FIG. 1 , the lid  17  is disposed on the surface  132  of the encapsulant  13  by the adhesive  19 . The adhesive  19  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 1 , the adhesive  19  is substantially arranged on the surface  132  of the encapsulant  13  and the side surface  135  of the encapsulant  13  which is connected to the surfaces  131  and  132  of the encapsulant  13 . That is, the adhesive  19  is arranged at the recessed portion of the carrier  10  and is substantially between the lid  17  and the carrier  10 . Moreover, since the adhesive  19  is arranged at the recessed portion of the carrier  10 , the adhesive  19  may not bleed on the surface  131  and the surface  111  to cover the wire  151 . The wire  151  is not pulled and dragged by the adhesive  19  during the assembly process, e.g., heating or curing process. The lid  17  has a surface  172  supported by the surface  132  of the encapsulant  13 . Thus, the surface  172  of the lid  17  is elevationally less than the surface  131  of the encapsulant  13  and the surface  111  of the redistribution structure  11 . In other words, the surface  172  of the lid  17  and the surface  131  of the encapsulant  13  and the surface  111  of the redistribution structure  11  are disposed in different elevations. In some embodiments, the surface  173  of the lid  17  and the side surface  133  of the encapsulant  13  may not be coplanar with each other. 
     The lid  17  has an aperture  175  at its top and the aperture  175  is substantially aligned with the optical element  15 . A filter material  18  is arranged within the aperture  175 . Moreover, since the lid  17  may be formed by injection molding, the roughness of the outer surface of the lid  17  may be substantially unified. That is, the roughness of the side surface  173  of the lid  17  may be identical to the roughness of the top surface  171  of the lid  17 . 
       FIG. 2  illustrates a cross-sectional view of an optical device package  1  in accordance with some embodiments of the present disclosure. The optical device package  1  shown in  FIG. 2  is similar in certain respects to the optical device package  1  shown in  FIG. 1 , except that in  FIG. 2 , a substrate  100  is attached to the surface  134  of the encapsulant  13 , which is opposite the surface  131  of the encapsulant  13 , and electrically connected to the electrical connections  12 . In addition, the electrical connections  12  may not be exposed. Thus, in at least some embodiments, the optical device package  1  further comprises a substrate  100 , and the encapsulant  13  encapsulates the surface  112  and the side surfaces  113  of the redistribution structure  11 , the surface  101  of the substrate  100  and the electrical connections  12 . 
       FIG. 3  illustrates a cross-sectional view of an optical device package  2  in accordance with some embodiments of the present disclosure. The optical device package  2  comprises a carrier  20  and a lid  27 . In some embodiments, the carrier  20  may include ceramic material or a metal plate. In some embodiments, the carrier  20  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  20  may include a plurality of traces. The carrier  20  illustrated in  FIG. 3  comprises a redistribution structure  21 , electrical connections  22 , an encapsulant  23 , a semiconductor device  24 , optical elements  25  and an under-fill layer  26 . 
     The redistribution structure  21  has a surface  211  and a surface  212  opposite the surface  211 . At least one of the electrical connections  22  is on the surface  212  of the redistribution structure  21 . The encapsulant  23  encapsulates the surface  212  and the side surface  213  of the redistribution structure  21  and the electrical connections  22 . A portion of each electrical connection  22  is exposed by the encapsulant  23 . 
     The semiconductor device  24  is mounted on the surface  212  of the redistribution structure  21 . The semiconductor device  24  and the redistribution structure  21  are electrically connected by the bumps  241 . In some embodiments, the space between the bumps  241  is filled with an under-fill layer  26 . The electrical connections  22  surround a periphery of the semiconductor device  24  and are used to fan-out the inputs and outputs of the semiconductor device  24 . The optical elements  25  are mounted on and electrically connected to the surface  211  of the redistribution structure  21 . Regarding these two optical elements  25 , they may be two optical emitters or two optical detectors or one is an optical emitter and the other is an optical detector. 
     As shown in  FIG. 3 , the encapsulant  23  encapsulates the surface  212  and the side surface  213  of the redistribution structure  21  and the electrical connections  22 . The encapsulant  23  has a surface  231 , a surface  232  recessed with respect to the surface  231  and a surface  235  connecting the surfaces  231  and  232 . The surface  231  of the encapsulant  23  may be substantially coplanar with the surface  211  of the redistribution structure  21 , and thus the surface  232  of the encapsulant  23  is elevationally less than the surface  231  of the encapsulant  23  and the surface  211  of the redistribution structure  21 . In addition, the surface  232  is adjacent to the side surface  233  of the encapsulant  23 . 
     Given the above, referring to  FIG. 3 , the carrier  20  has a recessed portion at its side, which is formed by the surfaces  232  and  235 . 
     Further, a lid  27  is arranged on the carrier  10 . Referring to  FIG. 3 , the lid  27  is disposed on the surface  211  of the redistribution structure  21  and the surface  232  of the encapsulant  23  by the adhesive  29 . The adhesive  29  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 3 , the adhesive  29  is substantially arranged on the surface  232  of the encapsulant  23  and the side surface  235  of the encapsulant  23  which is connected to the surfaces  231  and  232  of the encapsulant  23  and arranged on the first surface  211  of the redistribution structure  21 . That is, the adhesive  29  is arranged at the recessed portion of the carrier  20  and is substantially between the lid  27  and the carrier  20 . Moreover, since the adhesive  29  is arranged at the recessed portion of the carrier  20 , the adhesive  29  may not bleed on the surface  231  and the surface  211  to cover the wire  251 . The wire  251  is not pulled and dragged by the adhesive  29  during the assembly process, e.g., heating or curing process. The lid  27  has a surface  272  supported by the surface  232  of the encapsulant  23 . Thus, the surface  272  of the lid  27  is elevationally less than the surface  231  of the encapsulant  13  and the surface  211  of the redistribution structure  21 . In other words, the surface  272  of the lid  27  and the surface  231  of the encapsulant  23  and the surface  211  of the redistribution structure  21  are disposed in the different elevations. In addition, the lid  27  may have an inner wall  274  which isolates the optical elements  25  from each other. The inner wall  274  of the lid  27  has a surface  276  supported by the surface  211  of the redistribution structure  21 . Thus, the surface  272  is elevationally less than the surface  276 . That is, the surfaces  272  and  276  of the lid  27  are disposed in different elevations. In some embodiments, the surface  273  of the lid  27  and the side surface  233  of the encapsulant  23  may not be coplanar with each other. 
     The lid  27  has two apertures  275  at its top and each of the apertures  275  is substantially aligned with the optical element  25 . Further, the filter materials  28  are respectively arranged within the aperture  275 . Moreover, since the lid  27  may be formed by injection molding, the roughness of the outer surface of the lid  27  may be substantially unified. That is, the roughness of the side surface  273  of the lid  27  may be identical to the roughness of the top surface  271  of the lid  27 . 
       FIG. 4  illustrates a cross-sectional view of an optical device package  2  in accordance with some embodiments of the present disclosure. The optical device package  2  shown in  FIG. 4  is similar in certain respects to the optical device package  2  shown in  FIG. 3 , except that in  FIG. 4 , the substrate  200  is attached to the surface  234  of the encapsulant  23 , which is opposite the surface  231  of the encapsulant  23 , and electrically connected to the electrical connections  22 . In addition, the electrical connections  22  may not be exposed. Thus, in at least some embodiments, the optical device package  2  further comprises a substrate  200 , and the encapsulant  23  encapsulates the surface  212  and the side surfaces  213  of the redistribution structure  21 , the surface  201  of the substrate  200  and the electrical connections  22 . 
       FIG. 5  illustrates a cross-sectional view of an optical device package  3  in accordance with some embodiments of the present disclosure. The optical device package  3  comprises a carrier  30  and a lid  37 . In some embodiments, the carrier  30  may include ceramic material or a metal plate. In some embodiments, the carrier  30  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  30  may include a plurality of traces. The carrier  30  illustrated in  FIG. 5  comprises a redistribution structure  31 , electrical connections  32 , an encapsulant  33 , a semiconductor device  34 , an optical element  35  and an under-fill layer  36 . 
     The redistribution structure  31  has a surface  311  and a surface  312  opposite the surface  311 . At least one of the electrical connections  32  is on the surface  312  of the redistribution structure  31 . The encapsulant  33  encapsulates the surface  312  of the redistribution structure  31  and the electrical connections  32 . A portion of each electrical connection  32  is exposed by the encapsulant  33 . In addition, the redistribution structure  31  has a side surface  313 , and some plating lines may be exposed on the side surface  313 . 
     The semiconductor device  34  is mounted on the surface  312  of the redistribution structure  31 . The semiconductor device  34  and the redistribution structure  31  are electrically connected by the bumps  341 . In some embodiments, the space between the bumps  341  is filled with an under-fill layer  36 . The electrical connections  32  surround a periphery of the semiconductor device  34  and are used to fan-out the inputs and outputs of the semiconductor device  34 . The optical element  35  (e.g., optical emitter or optical detector) is mounted on and electrically connected to the surface  311  of the redistribution structure  31 . 
     As shown in  FIG. 5 , the encapsulant  33  encapsulates the surface  312  of the redistribution structure  31  and the electrical connections  32 . Thus, the encapsulant  33  has a surface  331  recessed with respect to the surface  311  of the redistribution structure  31  and adjacent to the side surface  313  of the redistribution structure  31 . That is, the surface  331  of the encapsulant  33  is elevationally less than the surface  311  of the redistribution structure  31 . In addition, the surface  331  of the encapsulant  33  may be coplanar with the surface  312  of the redistribution structure  31 . 
     Given the above, referring to  FIG. 5 , the carrier  30  has a recessed portion at its side, which is formed by the surfaces  331  and  313 . 
     Further, a lid  37  is arranged on the carrier  30 . Referring to  FIG. 5 , the lid  37  is disposed on the surface  331  of the encapsulant  13  by the adhesive  39 . The adhesive  39  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 5 , the adhesive  39  is substantially arranged on the surface  331  of the encapsulant  33  and the side surface  313  of the redistribution structure  31 , which connects the surface  311  of the redistribution structure  31  and the surface  331  of the encapsulant  33 . That is, the adhesive  39  is arranged at the recessed portion of the carrier  30  and is substantially between the lid  37  and the carrier  30 . Moreover, since the adhesive  39  is arranged at the recessed portion of the carrier  30 , the adhesive  39  may not bleed on the surface  311  to cover contact the wire  351 . The wire  351  is not pulled and dragged by the adhesive  39  during the assembly process, e.g., heating or curing process. The lid  37  has a surface  372  supported by the surface  332  of the encapsulant  33 . Thus, the surface  372  of the lid  37  is elevationally less than the surface  311  of the redistribution structure  31 . In other words, the surface  372  of the lid  37  and the surface  311  of the redistribution structure  31  are disposed in different elevations. In some embodiments, the surface  373  of the lid  37  and the side surface  333  of the encapsulant  33  may not be coplanar with each other. 
     The lid  37  has an aperture  375  at its top and the aperture  375  is substantially aligned with the optical element  35 . A filter material  38  is arranged within the aperture  375 . Moreover, since the lid  37  may be formed by injection molding, the roughness of the outer surface of the lid  37  may be substantially unified. That is, the roughness of the side surface  373  of the lid  37  may be identical to the roughness of the top surface  371  of the lid  37 . 
       FIG. 6  illustrates a cross-sectional view of an optical device package  3  in accordance with some embodiments of the present disclosure. The optical device package  3  shown in  FIG. 6  is similar in certain respects to the optical device package  3  shown in  FIG. 5 , except that in  FIG. 6 , a substrate  300  is attached to the surface  334  of the encapsulant  33 , which is opposite the surface  331  of the encapsulant  33 , and electrically connected to the electrical connections  32 . In addition, the electrical connections  32  may not be exposed. Thus, in at least some embodiments, the optical device package  3  further comprises a substrate  300 , and the encapsulant  33  encapsulates the surface  312  of the redistribution structure  31 , the surface  301  of the substrate  300  and the electrical connections  32 . 
       FIG. 7  illustrates a cross-sectional view of an optical device package  4  in accordance with some embodiments of the present disclosure. The optical device package  4  comprises a carrier  40  and a lid  47 . In some embodiments, the carrier  40  may include ceramic material or a metal plate. In some embodiments, the carrier  40  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  40  may include a plurality of traces. The carrier  40  illustrated in  FIG. 7  comprises a redistribution structure  41 , electrical connections  42 , an encapsulant  43 , a semiconductor device  44 , optical elements  45  and an under-fill layer  46 . 
     The redistribution structure  41  has a surface  411  and a surface  412  opposite the surface  411 . At least one of the electrical connections  42  is on the surface  412  of the redistribution structure  41 . The encapsulant  43  encapsulates the surface  412  of the redistribution structure  41  and the electrical connections  42 . A portion of each electrical connection  42  is exposed by the encapsulant  43 . In addition, the redistribution structure  41  has a side surface  413 , and some plating lines may be exposed on the side surface  413 . 
     The semiconductor device  44  is mounted on the surface  412  of the redistribution structure  41 . The semiconductor device  44  and the redistribution structure  41  are electrically connected by the bumps  441 . In some embodiments, the space between the bumps  441  is filled with an under-fill layer  46 . The electrical connections  42  surround a periphery of the semiconductor device  44  and are used to fan-out the inputs and outputs of the semiconductor device  44 . The optical elements  45  are mounted on and electrically connected to the surface  411  of the redistribution structure  41 . Regarding these two optical elements  45 , they may be two optical emitters or two optical detectors or one is an optical emitter and the other is an optical detector. 
     As shown in  FIG. 7 , the encapsulant  43  encapsulates the surface  412  of the redistribution structure  41  and the electrical connections  42 . The encapsulant  43  has a surface  431  recessed with respect to the surface  411  of the redistribution structure  41  and adjacent to the side surface  413  of the redistribution structure  41 . Thus, the surface  431  of the encapsulant  43  is elevationally less than the surface  411  of the redistribution structure  41 . In addition, the surface  431  of the encapsulant  43  may be coplanar with the surface  412  of the redistribution structure  41 . 
     Given the above, referring to  FIG. 7 , the carrier  40  has a recessed portion at its side, which is formed by the surfaces  431  and  413 . 
     Further, a lid  47  is arranged on the carrier  40 . Referring to  FIG. 7 , the lid  47  is disposed on the surface  411  of the redistribution structure  41  and the surface  431  of the encapsulant  43  by the adhesive  49 . The adhesive  49  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 7 , the adhesive  49  is substantially arranged on the surface  431  of the encapsulant  43  and the side surface  413  of the redistribution structure  41 , which connects to the surface  411  of the redistribution structure  41  and the surface  431  of the encapsulant  43 , and arranged on the surface  411  of the redistribution structure  41 . That is, the adhesive  49  is arranged at the recessed portion of the carrier  47  and is substantially between the lid  47  and the carrier  40 . Moreover, since the adhesive  49  is arranged at the recessed portion of the carrier  40 , the adhesive  49  may not bleed on the surface  411  to cover the wire  451 . The wire  451  is not pulled and dragged by the adhesive  49  during the assembly process, e.g., heating or curing process. The lid  47  has a surface  472  supported by the surface  431  of the encapsulant  43 . Thus, the surface  472  of the lid  47  is elevationally less than the surface  431  of the encapsulant  43 . In other words, the surface  472  of the lid  47  and the surface  411  of the redistribution structure  41  are disposed in the different elevations. In addition, the lid  47  may have an inner wall  474  which isolates the optical elements  45  from each other. The inner wall  474  of the lid  47  has a surface  476  supported by the surface  411  of the redistribution structure  41 . Thus, the surface  472  is elevationally less than the surface  476 . That is, the surfaces  472  and  476  of the lid  47  are disposed in different elevations. In some embodiments, the surface  473  of the lid  47  and the side surface  433  of the encapsulant  43  may not be coplanar with each other. 
     The lid  47  has two apertures  475  at its top and each of the apertures  475  is substantially aligned with the optical elements  45 . Further, the filter materials  48  are respectively arranged within the aperture  475 . Moreover, since the lid  47  may be formed by injection molding, the roughness of the outer surface of the lid  47  may be substantially unified. That is, the roughness of the side surface  473  of the lid  47  may be identical to the roughness of the top surface  471  of the lid  47 . 
       FIG. 8  illustrates a cross-sectional view of an optical device package  4  in accordance with some embodiments of the present disclosure. The optical device package  4  shown in  FIG. 8  is similar in certain respects to the optical device package  4  shown in  FIG. 7 , except that in  FIG. 8 , a substrate  400  is attached to the surface  434  of the encapsulant  43 , which is opposite the surface  431  of the encapsulant  43 , and electrically connected to the electrical connections  42 . In addition, the electrical connections  42  may not be exposed. Thus, in at least some embodiments, the optical device package  4  further comprises a substrate  400 , and the encapsulant  43  encapsulates the surface  412  of the redistribution structure  41 , the surface  401  of the substrate  400  and the electrical connections  42 . 
       FIG. 9  illustrates a cross-sectional view of an optical device package  5  in accordance with some embodiments of the present disclosure. The optical device package  5  comprises a carrier  50  and a lid  57 . In some embodiments, the carrier  50  may include ceramic material or a metal plate. In some embodiments, the carrier  50  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  50  may include a plurality of traces. The carrier  50  illustrated in  FIG. 9  comprises a redistribution structure  51 , electrical connections  52 , an encapsulant  53 , a semiconductor device  54 , an optical element  55  and an under-fill layer  56 . 
     The redistribution structure  51  has a surface  511 , a surface  512  recessed with respect to the  511 , a surface  513  opposite the surfaces  511  and  512 , a surface  514  connecting the surfaces  512  and  513  and a surface  515  connecting the surfaces  511  and  512 . At least one of the electrical connections  52  is on the surface  513  of the redistribution structure  51 . The encapsulant  53  encapsulates the surface  513  and the side surface  514  of the redistribution structure  51  and the electrical connections  52 . A portion of each electrical connection  52  is exposed by the encapsulant  53 . In addition, some plating lines may be exposed on the surface  515  of the redistribution structure  51 . 
     The semiconductor device  54  is mounted on the surface  513  of the redistribution structure  51 . The semiconductor device  54  and the redistribution structure  51  are electrically connected by the bumps  541 . In some embodiments, the space between the bumps  541  is filled with an under-fill layer  56 . The electrical connections  52  surround a periphery of the semiconductor device  54  and are used to fan-out the inputs and outputs of the semiconductor device  54 . The optical element  55  (e.g., optical emitter or optical detector) is mounted on and electrically connected to the surface  511  of the redistribution structure  51 . 
     As above-mentioned, the redistribution structure  51  has a surface  511 , a surface  512  recessed with respect to the  511  and a surface  513  opposite the surfaces  511  and  512 , and the encapsulant  53  encapsulates the surface  513  and the side surface  513  of the redistribution structure  51  and the electrical connections  52 . The encapsulant  53  has a surface  531  which may be adjacent to and coplanar with the surface  512  of the redistribution structure  51 . That is, the surface  512  of the redistribution structure  51  and the surface  531  of the encapsulant  53  is elevationally less than the surface  511  of the redistribution structure  51 . 
     Given the above, referring to  FIG. 9 , the carrier  50  has a recessed portion at its side, which is formed by the surfaces  515 ,  512  and  531 . 
     Further, a lid  57  is arranged on the carrier  50 . Referring to  FIG. 9 , the lid  57  is disposed on the surface  512  of the redistribution structure  51  and the surface  531  of the encapsulant  53  by the adhesive  59 . The adhesive  59  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 9 , the adhesive  59  is substantially arranged on the surface  531  of the encapsulant  53 , the surface  512  of the redistribution structure  51  and the side surface  515  of the redistribution structure  51  which is connected to the surfaces  511  and  512  of the redistribution structure  51 . That is, the adhesive  59  is arranged at the recessed portion of the carrier  50  and is substantially between the lid  57  and the carrier  50 . Moreover, since the adhesive  59  is arranged at the recessed portion of the carrier  50 , the adhesive  59  may not bleed on the surface  511  to cover the wire  551 . The wire  551  is not pulled and dragged by the adhesive  59  during the assembly process, e.g., heating or curing process. The lid  57  has a surface  572  supported by the surface  512  of the redistribution structure  51  and the surface  531  of the encapsulant  53 . Thus, the surface  572  of the lid  57  is elevationally less than the surface  511  of the redistribution structure  51 . In other words, the surface  572  of the lid  57  and the surface  511  of the redistribution structure  51  are disposed in different elevations. In some embodiments, the surface  573  of the lid  57  and the side surface  533  of the encapsulant  53  may not be coplanar with each other. 
     The lid  57  has an aperture  575  at its top and the aperture  575  is substantially aligned with the optical element  55 . A filter material  58  is arranged within the aperture  575 . Moreover, since the lid  57  may be formed by injection molding, the roughness of the outer surface of the lid  57  may be substantially unified. That is, the roughness of the side surface  573  of the lid  57  may be identical to the roughness of the top surface  571  of the lid  57 . 
       FIG. 10  illustrates a cross-sectional view of an optical device package  5  in accordance with some embodiments of the present disclosure. The optical device package  5  shown in  FIG. 10  is similar in certain respects to the optical device package  5  shown in  FIG. 9 , except that in  FIG. 10 , a substrate  500  is attached to the surface  534  of the encapsulant  53 , which is opposite the surface  531  of the encapsulant  53 , and electrically connected to the electrical connections  52 . In addition, the electrical connections  52  may not be exposed. Thus, in at least some embodiments, the optical device package  5  further comprises a substrate  500 , and the encapsulant  53  encapsulates the surface  513  and the side surface  514  of the redistribution structure  51 , the surface  501  of the substrate  500  and the electrical connections  52 . 
       FIG. 11  illustrates a cross-sectional view of an optical device package  6  in accordance with some embodiments of the present disclosure. The optical device package  6  comprises a carrier  60  and a lid  67 . In some embodiments, the carrier  60  may include ceramic material or a metal plate. In some embodiments, the carrier  60  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  60  may include a plurality of traces. The carrier  60  illustrated in  FIG. 11  comprises a redistribution structure  61 , electrical connections  62 , an encapsulant  63 , a semiconductor device  64 , optical elements  65  and an under-fill layer  66 . 
     The redistribution structure  61  has a surface  611 , a surface  612  recessed with respect to the  611 , a surface  613  opposite the surfaces  611  and  612 , a surface  614  connecting the surfaces  612  and  613  and a surface  615  connecting the surfaces  611  and  612 . At least one of the electrical connections  62  is on the surface  613  of the redistribution structure  51 . The encapsulant  63  encapsulates the surface  613  and the side surface  614  of the redistribution structure  61  and the electrical connections  62 . A portion of each electrical connection  62  is exposed by the encapsulant  63 . In addition, some plating lines may be exposed on the surface  515  of the redistribution structure  51 . 
     The semiconductor device  64  is mounted on the surface  613  of the redistribution structure  61 . The semiconductor device  64  and the redistribution structure  61  are electrically connected by the bumps  641 . In some embodiments, the space between the bumps  641  is filled with an under-fill layer  66 . The electrical connections  62  surround a periphery of the semiconductor device  64  and are used to fan-out the inputs and outputs of the semiconductor device  64 . The optical elements  65  are mounted on and electrically connected to the surface  611  of the redistribution structure  61 . Regarding these two optical elements  65 , they may be two optical emitters or two optical detectors or one is an optical emitter and the other is an optical detector. 
     As above-mentioned, the redistribution structure  61  has a surface  11 , a surface  12  recessed with respect to the  611  and a surface  613  opposite the surfaces  611  and  612 , and the encapsulant  63  encapsulates the surface  613  and the side surface  613  of the redistribution structure  61  and the electrical connections  62 . The encapsulant  63  has a surface  631  which may be adjacent to and coplanar with the surface  612  of the redistribution structure  61 . That is, the surface  612  of the redistribution structure  61  and the surface  631  of the encapsulant  63  is elevationally less than the surface  611  of the redistribution structure  61 . 
     Given the above, referring to  FIG. 11 , the carrier  60  has a recessed portion at its side, which is formed by the surfaces  615 ,  612  and  631 . 
     Further, a lid  67  is arranged on the carrier  60 . Referring to  FIG. 11 , the lid  67  is disposed on the surface  611  of the redistribution structure  61 , the surface  612  of the redistribution structure  61  and the surface  631  of the encapsulant  63  by the adhesive  69 . The adhesive  69  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 11 , the adhesive  69  is substantially arranged on the surface  611  of the redistribution structure  61 , the surface  631  of the encapsulant  63 , the surface  612  of the redistribution structure  61  and the side surface  615  of the redistribution structure  61  which is connected to the surfaces  611  and  612  of the redistribution structure  61 . That is, the adhesive  69  is arranged at the recessed portion of the carrier  60  and is substantially between the lid  67  and the carrier  60 . Moreover, since the adhesive  69  is arranged at the recessed portion of the carrier  60 , the adhesive  69  may not bleed on the surface  611  to cover the wire  651 . The wire  651  is not pulled and dragged by the adhesive  69  during the assembly process, e.g., heating or curing process. The lid  67  has a surface  672  supported by the surface  612  of the redistribution structure  61  and the surface  631  of the encapsulant  63 . Thus, the surface  672  of the lid  67  is elevationally less than the surface  611  of the redistribution structure  61 . In other words, the surface  672  of the lid  67  and the surface  611  of the redistribution structure  61  are disposed in different elevations. In addition, the lid  67  may have an inner wall  674  which isolates the optical elements  65  from each other. The inner wall  674  of the lid  67  has a surface  676  supported by the surface  611  of the redistribution structure  61 . Thus, the surface  672  is elevationally less than the surface  676 . That is, the surfaces  672  and  676  of the lid  67  are disposed in different elevations. In some embodiments, the surface  673  of the lid  67  and the side surface  633  of the encapsulant  63  may not be coplanar with each other. 
     The lid  67  has two apertures  675  at its top and each of the apertures  675  is substantially aligned with the optical elements  65 . Further, the filter materials  68  are respectively arranged within the aperture  675 . Moreover, since the lid  67  may be formed by injection molding, the roughness of the outer surface of the lid  67  may be substantially unified. That is, the roughness of the side surface  673  of the lid  67  may be identical to the roughness of the top surface  671  of the lid  67 . 
       FIG. 12  illustrates a cross-sectional view of an optical device package  6  in accordance with some embodiments of the present disclosure. The optical device package  6  shown in  FIG. 11  is similar in certain respects to the optical device package  6  shown in  FIG. 12 , except that in  FIG. 11 , a substrate  600  is attached to the surface  634  of the encapsulant  63 , which is opposite the surface  631  of the encapsulant  63 , and electrically connected to the electrical connections  62 . In addition, the electrical connections  62  may not be exposed. Thus, in at least some embodiments, the optical device package  6  further comprises a substrate  600 , and the encapsulant  63  encapsulates the surface  613  and the side surface  614  of the redistribution structure  61 , the surface  601  of the substrate  600  and the electrical connections  62 . 
       FIG. 13  illustrates a cross-sectional view of an optical device package  7  in accordance with some embodiments of the present disclosure. The optical device package  7  comprises a carrier  70  and a lid  77 . In some embodiments, the carrier  70  may include ceramic material or a metal plate. In some embodiments, the carrier  70  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  70  may include a plurality of traces. The carrier  70  illustrated in  FIG. 13  comprises a redistribution structure  71 , electrical connections  72 , an encapsulant  73 , a semiconductor device  74 , an optical element  75  and an under-fill layer  76 . 
     The redistribution structure  71  has a surface  711  and a surface  712  opposite the surface  711 . At least one of the electrical connections  72  is on the surface  712  of the redistribution structure  71 . The encapsulant  73  encapsulates the surface  712  of the redistribution structure  71  and the electrical connections  72 . A portion of each electrical connection  72  is exposed by the encapsulant  73 . In addition, the redistribution structure  71  has a side surface  713 , and some plating lines may be exposed on the side surface  713 . 
     The semiconductor device  74  is mounted on the surface  712  of the redistribution structure  71 . The semiconductor device  74  and the redistribution structure  71  are electrically connected by the bumps  741 . In some embodiments, the space between the bumps  741  is filled with an under-fill layer  76 . The electrical connections  72  surround a periphery of the semiconductor device  74  and are used to fan-out the inputs and outputs of the semiconductor device  74 . The optical element  75  (e.g., optical emitter or optical detector) is mounted on and electrically connected to the surface  711  of the redistribution structure  71 . 
     As shown in  FIG. 13 , the encapsulant  73  encapsulates the surface  712  of the redistribution structure  71  and the electrical connections  72 . The encapsulant  73  has a surface  731 , a surface  732  recessed with respect to the surface  731  and a side surface  735  connected to the surface  731  and the surface  732 . The surface  731  of the encapsulant  73  is substantially attached to the  712  of the redistribution structure  71 . The side surface  735  of the encapsulant  73  may be adjacent to the side surface  713  of the redistribution structure  71  and substantially coplanar with the side surface  713  of the redistribution structure  71 . Referring to  FIG. 13 , the surface  732  of the encapsulant  73  is elevationally less than the surface  711  of the redistribution structure  71 . 
     Given the above, referring to  FIG. 13 , the carrier  70  has a recessed portion at its side, which is formed by the surfaces  713 ,  732  and  735 . 
     Further, a lid  77  is arranged on the carrier  70 . Referring to  FIG. 13 , the lid  77  is disposed on the surface  732  of the encapsulant  73  by the adhesive  79 . The adhesive  79  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 13 , the adhesive  79  is substantially arranged on the surface  732  of the encapsulant  73 , the side surface  735  of the encapsulant  73 , which connects the surface  732  of the encapsulant  73 , and the side surface  713  of the redistribution structure  71 , which connects the surface  711  of the redistribution structure  71 . That is, the adhesive  79  is arranged at the recessed portion of the carrier  70  and is substantially between the lid  77  and carrier  70 . Moreover, since the adhesive  79  is arranged at the recessed portion of the carrier  70 , the adhesive  79  may not bleed on the surface  711  to cover the wire  751 . The wire  751  is not pulled and dragged by the adhesive  79  during the assembly process, e.g., heating or curing process. The lid  77  has a surface  772  supported by the surface  732  of the encapsulant  73 . Thus, the surface  772  of the lid  77  is elevationally less than the surface  731  of the encapsulant  73  and the surface  711  of the redistribution structure  71 . In other words, the surface  772  of the lid  77  and the surface  731  of the encapsulant  73  and the surface  711  of the redistribution structure  71  are disposed in different elevations. In some embodiments, the surface  773  of the lid  77  and the side surface  733  of the encapsulant  73  may not be coplanar with each other. 
     The lid  77  has an aperture  775  at its top and the aperture  775  is substantially aligned with the optical element  75 . A filter material  78  is arranged within the aperture  775 . Moreover, since the lid  77  may be formed by injection molding, the roughness of the outer surface of the lid  77  may be substantially unified. That is, the roughness of the side surface  773  of the lid  77  may be identical to the roughness of the top surface  771  of the lid  77 . 
       FIG. 14  illustrates a cross-sectional view of an optical device package  7  in accordance with some embodiments of the present disclosure. The optical device package  7  shown in  FIG. 14  is similar in certain respects to the optical device package  7  shown in  FIG. 13 , except that in  FIG. 14 , a substrate  700  is attached to the surface  734  of the encapsulant  73 , which is opposite the surfaces  731  and  732  of the encapsulant  73 , and electrically connected to the electrical connections  72 . In addition, the electrical connections  72  may not be exposed. Thus, in at least some embodiments, the optical device package  7  further comprises a substrate  700 , and the encapsulant  73  encapsulates the surface  712  of the redistribution structure  71 , the surface  701  of the substrate  700  and the electrical connections  72 . 
       FIG. 15  illustrates a cross-sectional view of an optical device package  8  in accordance with some embodiments of the present disclosure. The optical device package  8  comprises a carrier  80  and a lid  87 . In some embodiments, the carrier  80  may include ceramic material or a metal plate. In some embodiments, the carrier  80  may be a substrate, an organic substrate or a leadframe. In some embodiment, the carrier  80  may include a plurality of traces. The carrier  80  illustrated in  FIG. 15  comprises a redistribution structure  81 , electrical connections  82 , an encapsulant  83 , a semiconductor device  84 , optical elements  85  and an under-fill layer  86 . 
     The redistribution structure  81  has a surface  811  and a surface  812  opposite the surface  811 . At least one of the electrical connections  82  is on the surface  812  of the redistribution structure  81 . The encapsulant  83  encapsulates the surface  812  of the redistribution structure  81  and the electrical connections  82 . A portion of each electrical connection  82  is exposed by the encapsulant  83 . In addition, the redistribution structure  81  has a side surface  813 , and some plating lines may be exposed on the side surface  813 . 
     The semiconductor device  84  is mounted on the surface  812  of the redistribution structure  81 . The semiconductor device  84  and the redistribution structure  81  are electrically connected by the bumps  841 . In some embodiments, the space between the bumps  841  is filled with an under-fill layer  86 . The electrical connections  82  surround a periphery of the semiconductor device  84  and are used to fan-out the inputs and outputs of the semiconductor device  84 . The optical elements  85  are mounted on and electrically connected to the surface  811  of the redistribution structure  81 . Regarding these two optical elements  85 , they may be two optical emitters or two optical detectors or one is an optical emitter and the other is an optical detector. 
     As shown in  FIG. 15 , the encapsulant  83  encapsulates the surface  812  of the redistribution structure  81  and the electrical connections  82 . The encapsulant  83  has a surface  831 , a surface  832  recessed with respect to the surface  831  and a side surface  833  connected to the surface  831  and the surface  832 . The surface  831  of the encapsulant  83  is substantially attached to the  812  of the redistribution structure  81 . The side surface  833  of the encapsulant  83  may be adjacent to the side surface  813  of the redistribution structure  81  and substantially coplanar with the side surface  813  of the redistribution structure  81 . Referring to  FIG. 15 , the surface  832  of the encapsulant  83  is elevationally less than the surface  811  of the redistribution structure  81 . 
     Given the above, referring to  FIG. 15 , the carrier  80  has a recessed portion at its side, which is formed by the surfaces  813 ,  832  and  835 . 
     Further, a lid  87  is arranged on the carrier  80 . Referring to  FIG. 15 , the lid  87  is disposed on the surface  811  of the redistribution structure  81  and the surface  832  of the encapsulant  83  by the adhesive  89 . The adhesive  89  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Especially, as shown in to  FIG. 15 , the adhesive  89  is substantially arranged on the surface  811  of the redistribution structure  81 , the surface  832  of the encapsulant  83 , the side surface  833  of the encapsulant  83   m  which connects the surface  832  of the encapsulant  83 , and the side surface  813  of the redistribution structure  81 , which connects the surface  811  of the redistribution structure  81 . That is, the adhesive  89  is arranged at the recessed portion of the carrier  80  and is substantially between the lid  87  and the carrier  80 . 
     Moreover, since the adhesive  89  is arranged at the recessed portion of the carrier  80 , the adhesive  89  may not bleed on the surface  811  to cover contact the wire  851 . The wire  851  is not pulled and dragged by the adhesive  89  during the assembly process, e.g., heating or curing process. The lid  87  has a surface  872  supported by the surface  832  of the encapsulant  83 . Thus, the surface  872  of the lid  87  is elevationally less than the surface  831  of the encapsulant  83  and the surface  811  of the redistribution structure  81 . In other words, the surface  872  of the lid  87  and the surface  831  of the encapsulant  83  and the surface  811  of the redistribution structure  81  are disposed in different elevations. In addition, the lid  87  may have an inner wall  874  which isolates the optical elements  85  from each other. The inner wall  874  of the lid  87  has a surface  876  supported by the surface  811  of the redistribution structure  81 . Thus, the surface  672  is elevationally less than the surface  876 . That is, the surfaces  872  and  876  of the lid  87  are disposed in different elevations. In some embodiments, the surface  873  of the lid  87  and the side surface  835  of the encapsulant  83  may not be coplanar with each other. 
     The lid  87  has two apertures  875  at its top and each of the apertures  875  is substantially aligned with the optical elements  85 . Further, the filter materials  88  are respectively arranged within the aperture  875 . Moreover, since the lid  87  may be formed by injection molding, the roughness of the outer surface of the lid  87  may be substantially unified. That is, the roughness of the side surface  873  of the lid  87  may be identical to the roughness of the top surface  871  of the lid  87 . 
       FIG. 16  illustrates a cross-sectional view of an optical device package  8  in accordance with some embodiments of the present disclosure. The optical device package  8  shown in  FIG. 16  is similar in certain respects to the optical device package  8  shown in  FIG. 15 , except that in  FIG. 16 , a substrate  800  is attached to the surface  834  of the encapsulant  83 , which is opposite the surfaces  831  and  832  of the encapsulant  83 , and electrically connected to the electrical connections  82 . In addition, the electrical connections  82  may not be exposed. Thus, in at least some embodiments, the optical device package  8  further comprises a substrate  800 , and the encapsulant  83  encapsulates the surface  812  of the redistribution structure  81 , the surface  801  of the substrate  800  and the electrical connections  82 . 
       FIGS. 17A, 17B, 17C, 17D, 17E, 17F, 17G, 17H, 17I and 17J  illustrate one or more stages of a method of manufacturing optical device packages  2  in accordance with some embodiments of the present disclosure.  FIG. 17A  illustrates substrates (e.g., redistribution structures)  21  that have been processed through stages of: baking substrate strip. 
     As shown in  FIG. 17B , the following stages are then performed to the substrates  21 : mounting dies  24  onto the surfaces  212  of the substrates  21  by flip-chip (FC) bonding. 
     As shown in  FIG. 17C , the following stages are then performed to the substrates  21 : dispersing under-fill (UF)  26 ; and curing the UF  26 . 
     As shown in  FIG. 17D , the following stages are then performed to the substrates  21 : mounting electrical connections  22  onto the surfaces  212  of the substrates  21  the substrate. 
     As shown in  FIG. 17E , a substrate  200  is attached to and connected to the electrical connections  22 . 
     As shown in  FIG. 17F , a film-type molding compound (e.g., encapsulant)  23  is applied on the substrates  21 , the substrates  200 , the electrical connections  22  and the dies  24 . Thus, the encapsulant  23  encapsulates the side surfaces  213  and the surfaces  212  of the substrates  21 , the surface  201  the substrate  200  and the electrical connections  22  and the dies  24 . The encapsulant  23  has a surface  231 , wherein the surface  231  may be substantially coplanar with surfaces  211  of the substrates  21 , which are opposite the surfaces  212  of the substrates  21 . 
     As shown in  FIG. 17G , the following stages are then performed to the substrates  21 : cutting the substrate  200  and the encapsulant  23 . 
     As shown in  FIG. 17H , two optical elements  25  are mounted onto the surface  211  of the redistribution structure  21 . Regarding these two optical elements  25 , they may be two optical emitters or two optical detectors or one is an optical emitter and the other is an optical detector. 
     As shown in  FIG. 17I , a portion of the encapsulant  239  is removed. Thus, the encapsulant  23  has a surface  232  adjacent to the side surface  233  of the encapsulant  23  and recessed with respect to the surface  231  of the encapsulant  23 . 
     As shown in  FIG. 17J , a lid  27 , which may be formed by injection molding, is disposed on the surface  211  of the redistribution structure  21  and the surface  232  of the encapsulant  23  by the adhesive  29 . The adhesive  29  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Moreover, the apertures  275  of the lid  27  are substantially aligned with the optical elements  25 . Further, the lid  27  is formed before the lid  27  is disposed on the surface  211  of the redistribution structure  21  and the surface  232  of the encapsulant  23 , and thus the side surface  273  of the lid  27  may not be coplanar with the side surface  233  of the encapsulant  23 .  FIG. 17J  shows the optical device packages  2  in accordance with some embodiments of the present disclosure. 
       FIGS. 18A, 18B, 18C, 18D, 18E, 18F, 18G, 18H, 18I and 18J  illustrate one or more stages of a method of manufacturing optical device packages  6 ′ in accordance with some embodiments of the present disclosure.  FIG. 18A  illustrates substrates (e.g., redistribution structures)  61  that have been processed through stages of: baking substrate strip. Further, the substrate  61  comprises plating lines  617 . 
     As shown in  FIG. 18B , the following stages are then performed to the substrates  61 : mounting dies  64  onto the surfaces  613  of the substrates  61  by flip-chip (FC) bonding. 
     As shown in  FIG. 18C , the following stages are then performed to the substrates  61 : dispersing under-fill (UF)  66 ; and curing the UF  66 . 
     As shown in  FIG. 18D , the following stages are then performed to the substrates  61 : mounting electrical connections  62  onto the surfaces  613  of the substrates  61  the substrate. 
     As shown in  FIG. 18E , a substrate  600  is attached to and connected to the electrical connections  62 . 
     As shown in  FIG. 18F , a film-type molding compound (e.g., encapsulant)  63  is applied on the substrates  61 , the substrates  600 , the electrical connections  62  and the dies  64 . Thus, the encapsulant  63  encapsulates the side surfaces  614  and the surfaces  613  of the substrates  61 , the surface  601  the substrate  600  and the electrical connections  62  and the dies  64 . 
     As shown in  FIG. 18G , the following stages are then performed to the substrates  61 : cutting the substrate  600  and the encapsulant  63 . 
     As shown in  FIG. 18H , two optical elements  65  are mounted onto the surface  611  of the redistribution structure  61 . Regarding these two optical elements  65 , they may be two optical emitters or two optical detectors or one is an optical emitter and the other is an optical detector. 
     As shown in  FIG. 18I , a portion of the encapsulant  639  and a portion of the substrate (redistribution structure)  619  are removed. Thus, the redistribution structure  61  has a surface  612  recessed with respect to the surface  611  and a surface  615  connecting the surfaces  611  and  612  and the encapsulant  63  has a surface  631  substantially coplanar with the surface  612  of the redistribution structure  61 . Moreover, since a portion of the substrate (redistribution structure)  619  is removed, the plating lines  617  may be exposed on the surface  615  of the redistribution structure  61 . 
     As shown in  FIG. 18J , a lid  67 , which may be formed by injection molding, is disposed on the surface  612  of the redistribution structure  61  and the surface  631  of the encapsulant  63  by the adhesive  69 . The adhesive  69  may be the optical glue and the optical density (OD) value of the optical glue is greater than 3. Moreover, the apertures  675  of the lid  67  are substantially aligned with the optical elements  65 . Further, the lid  67  is formed before the lid  67  is disposed on the surface  612  of the redistribution structure  61  and the surface  631  of the encapsulant  63 , and thus the side surface  673  of the lid  67  may not be coplanar with the side surface  633  of the encapsulant  63 .  FIG. 18J  shows the optical device packages  6 ′ in accordance with some embodiments of the present disclosure. 
     As used herein, relative terms, such as “inner,” “interior,” “outer,” “exterior,” “top,” “bottom,” “front,” “back,” “upper,” “upwardly,” “lower,” “downwardly,” “vertical,” “vertically,” “lateral,” “laterally,” “above,” and “below,” refer to an orientation of a set of components with respect to one another; this orientation is in accordance with the drawings, but is not required during manufacturing or use. 
     As used herein, the singular terms “a,” “an,” and “the” may include plural referents unless the context clearly dictates otherwise. 
     As used herein, the terms “connect,” “connected,” and “connection” refer to an operational coupling or linking. Connected components can be directly or indirectly coupled to one another, for example, through another set of components. 
     As used herein, the terms “conductive,” “electrically conductive” and “electrical conductivity” refer to an ability to transport an electric current. Electrically conductive materials typically indicate those materials that exhibit little or no opposition to the flow of an electric current. One measure of electrical conductivity is Siemens per meter (S/m). Typically, an electrically conductive material is one having a conductivity greater than approximately 10 4  S/m, such as at least 10 5  S/m or at least 10 6  S/m. The electrical conductivity of a material can sometimes vary with temperature. Unless otherwise specified, the electrical conductivity of a material is measured at room temperature. 
     As used herein, the terms “approximately,” “substantially” “substantial,” and “about” refer to a considerable degree or extent. When used in conjunction with an event or situation, the terms can refer to instances in which the event or situation occurs precisely as well as instances in which the event or situation occurs to a close approximation, such as when accounting for typical tolerance levels of the manufacturing methods described herein. For example, when used in conjunction with a numerical value, the terms can refer to a range of variation less than or equal to +/−10% of that numerical value, such as less than or equal to +/−5%, less than or equal to +/−4%, less than or equal to +/−3%, less than or equal to +/−2%, less than or equal to +/−1%, less than or equal to +/−0.5%, less than or equal to +/−0.1%, or less than or equal to +/−0.05%. For example, two numerical values can be deemed to be “substantially” the same or equal if a difference between the values is less than or equal to +/−10% of an average of the values, such as less than or equal to +/−5%, less than or equal to +/−4%, less than or equal to +/−3%, less than or equal to +/−2%, less than or equal to +/−1%, less than or equal to +/−0.5%, less than or equal to +/−0.1%, or less than or equal to +1-0.05%. 
     Two surfaces can be deemed to be coplanar or substantially coplanar if a displacement between the two surfaces is no greater than 5 μm, no greater than 2 μm, no greater than 1 μm, or no greater than 0.5 μm. 
     A surface can be deemed to be planar or substantially planar if a difference between a highest point and a lowest point on the surface is no greater than 5 μm, no greater than 2 μm, no greater than 1 μm, or no greater than 0.5 μm. 
     Additionally, amounts, ratios, and other numerical values are sometimes presented herein in a range format. It is understood that such range formats are used for convenience and brevity, and should be interpreted flexibly to include numerical values explicitly specified as limits of a range, as well as all individual numerical values or sub-ranges encompassed within that range, as if each numerical value and sub-range is explicitly specified. 
     In the description of some embodiments, a component provided “on” or “over” another component can encompass cases where the former component is directly on (e.g., in physical contact with) the latter component, as well as cases where one or more intervening components are located between the former component and the latter component. 
     While the present disclosure has been described and illustrated with reference to specific embodiments thereof, these descriptions and illustrations do not limit the present disclosure. It should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the present disclosure as defined by the appended claims. 
     The construction and arrangement of the structures and methods as shown in the various example embodiments are illustrative only. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions and arrangement of the example embodiments without departing from the scope of the present disclosure.