Abstract:
In accordance with the present invention, there is provided multiple embodiments of a concentrated photovoltaic (CPV) module or package. In each embodiment of the present invention, the CPV module includes a mounting device or holder for use in maintaining an optical member or optical light guide of the module in a prescribed position relative to the solar cell or receiver die thereof.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     The present invention relates generally to semiconductor devices and, more particularly, to a concentrated photovoltaic (CPV) receiver module or package which includes a mounting device or holder for use in maintaining an optical member or optical light guide of the module or package in a prescribed position relative to the solar cell or receiver die thereof. 
     2. Description of the Related Art 
     Photovoltaic cells are a well known means for producing electrical current from electromagnetic radiation. Traditional photovoltaic cells comprise junction diodes fabricated from appropriately doped semiconductor materials. Such devices are typically fabricated as thin, flat wafers with the junction formed parallel to and near one of the flat surfaces. Photovoltaic cells are intended to be illuminated through their so-called “front” surface. Electromagnetic radiation absorbed by the semiconductor produces electron-hole pairs in the semiconductor. These electron-hole pairs may be separated by the electric field of the junction, thereby producing a photocurrent. Currently known photovoltaic cells typically have a generally quadrangular (e.g., square) configuration defining four peripheral side edges, and include a pair of bus bars which are disposed on the top or front surface and extend along respective ones of an opposed pair of the side edges. The bus bars are used to facilitate the electrical connection of the photovoltaic cell to another structure, as described in more detail below. 
     There is currently known in the electrical arts semiconductor devices known as CPV receiver die packages or modules. Currently known CPV modules typically comprise a ceramic substrate having a conductive pattern disposed on one side or face thereof. Attached to the substrate and electrically connected to the conductive pattern are electrical components, including a pair of preformed wire connectors and a packaged diode. Also attached to the substrate and electrically connected to the conductive pattern thereof is a CPV receiver cell or die. The electrical connection between the receiver die and the conductive pattern is often facilitated by a pair of punched thin metal foil or braided ribbon/mesh connectors which extend along and are welded or soldered to respective ones of opposed sides of the receiver die, which typically has a quadrangular or square configuration as indicated above. More particularly, the pair of punched thin metal foils or braided ribbon/mesh connectors are welded or soldered to respective ones of the bus bars on the top or front surface of the receiver die. In certain existing CPV modules, the electrical connection of the receiver die to the conductive pattern is facilitated by the use of multiple wires bonded to the bus bars on the front surface of the receiver die and the bond pads of the conductive pattern of the substrate, the wires being used as an alternative to the aforementioned braided ribbon or mesh interconnects. When wires are used as an alternative to the ribbon/mesh type interconnects, such wires require encapsulation, over-molding or other protection from the environment for long-term reliability of the CPV module including the same. 
     The CPV module may further include a light concentration means or optical light guide which is adapted to concentrate solar radiation onto the front surface of the receiver die. In this regard, CPV modules typically include a polished glass prism which is operatively connected to the solar cell or receiver die, and is used to guide the focused solar rays to the front surface of the receiver die. The prism also prevents light leak or mis-focused solar energy that may otherwise cause damage to the structures around the receiver die. 
     However, a drawback in the design of current CPV modules is that the aforementioned prisms require a special optical adhesive to attach the bottom surface thereof to the receiver die. The attachment of the prism to the receiver die through the use of the optical adhesive presents various problems in relation to the functionality of the CPV module. These problems include the possible delamination of the optical adhesive during transport or use of the CPV module, potential light loss through interface reflection or internal absorption, and optical adhesive “creep” on the sides of the prism that may cause light coupling loss or interference between the adhesive and incident light entering through the prism. In this regard, such interference may result in some of the incident light being lost, which in turn results in a lowering of the generation efficiency of electrical energy from the CPV module. 
     The present invention addresses these and other shortcomings of prior art CPV modules by providing a CPV module or package which includes a mounting device or holder for use in maintaining an optical member or optical light guide of the module or package in a prescribed position relative to the solar cell or receiver die thereof. These, and other features of the present invention will be described in more detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These, as well as other features of the present invention, will become more apparent upon reference to the drawings wherein: 
         FIG. 1A  is a top perspective view of a CPV module constructed in accordance with a first embodiment of the present invention; 
         FIG. 1B  is an exploded view of the CPV module shown in  FIG. 1A ; 
         FIG. 1C  is an enlarged, top perspective view of the receiver die assembly of CPV module shown in  FIG. 1B ; 
         FIG. 1D  is a cross-sectional view of the CPV module shown in  FIG. 1A ; 
         FIG. 2  is a cross-sectional view of a CPV module constructed in accordance with a second embodiment of the present invention; 
         FIG. 3  is a cross-sectional view of a CPV module constructed in accordance with a third embodiment of the present invention; 
         FIG. 4  is a top perspective view of the holder member of the receiver die assembly included in the CPV modules shown in  FIGS. 1D and 3 , the holder member used in conjunction with the CPV module shown in  FIG. 3  further including a block member; 
         FIG. 5  is a flow chart identifying an exemplary sequence of steps which may be used to facilitate the fabrication of the CPV module of the first embodiment shown in  FIGS. 1A-1D ; 
         FIGS. 6A-6D  are views illustrating an exemplary sequence of steps which may be used to facilitate the fabrication of the CPV module of the first embodiment corresponding to the steps identified in  FIG. 5 ; 
         FIG. 7  is a flow chart identifying an exemplary sequence of steps which may be used to facilitate the fabrication of the CPV module of the second embodiment shown in  FIG. 2 ; 
         FIG. 8  is a view illustrating one of the steps in the exemplary sequence of steps which may be used to facilitate the fabrication of the CPV module of the second embodiment corresponding to the steps identified in  FIG. 7 ; 
         FIG. 9  is a flow chart identifying an exemplary sequence of steps which may be used to facilitate the fabrication of the CPV module of the third embodiment shown in  FIG. 3 ; and 
         FIGS. 10 and 11  are views illustrating two of the steps in the exemplary sequence of steps which may be used to facilitate the fabrication of the CPV module of the third embodiment corresponding to the steps identified in  FIG. 9 . 
     
    
    
     Common reference numerals are used throughout the drawings and detailed description to indicate like elements. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings wherein the showings are for purposes of illustrating preferred embodiments of the present invention only, and not for purposes of limiting the same,  FIGS. 1A-1D  depict a CPV module  1000  constructed in accordance with a first embodiment of the present invention. The CPV module  1000  comprises a receiver die assembly  100  which is shown in detail in  FIG. 1C . The receiver die assembly  100  itself comprises a generally quadrangular (e.g., square) substrate  110  which defines a generally planar first (top) surface  111  and an opposed, generally planar second (bottom) surface  112 . The substrate  110  further includes a peripheral side surface which defines four generally straight peripheral side surface segments. The substrate  110  is preferably fabricated from silicon or ceramic, though the present invention is not intended to be limited to any specific material for the substrate  110 . 
     In addition to the substrate  110 , the receiver die assembly  100  comprises a solar cell or receiver die  120  which is attached or coupled to a central area of the first surface  111  of the substrate  110 . The receiver die  120  is adapted to receive sunlight, and to convert such sunlight into electrical energy. The receiver  120  itself has a generally quadrangular (e.g., square) configuration, and may be formed as a III-V solar cell, a II-IV solar cell, a silicon solar cell, or the like. More particularly, it is contemplated that the receiver die  120  may include an active layer, a dielectric layer, and a metal layer, with the receiver die  120  receiving photons from the active layer (which defines the active front surface thereof) to generate charge carriers (i.e., holes and electrons) in response to the received photons. To this end, the receiver die  120  may also have three junction layers, including a germanium (Ge) junction layer, a gallium arsenide (GaAs) junction layer and a gallium indium phosphide (GaInP) junction layer. It is contemplated that the aforementioned juncture layers will have different bandgap energies from one another, so that they absorb photons of energies in respective specific ranges. 
     The receiver die assembly  100  of the CPV module  1000  further comprises a conductive member  130  which is fabricated from a conductive material and is interposed or positioned between the receiver die  120  and the first surface  111  of the substrate  110  in the manner best shown in  FIG. 1D . In the receiver die assembly  100 , the conductive member  130  is electrically connected to the receiver die  120  through the use of a conductive connecting member  125 . In the receiver die assembly  100 , the connecting member  125  is preferably a gold wire, though those of ordinary skill in the art will recognize that the connecting member  125  may be fabricated from a conductive material other than for gold. Those of ordinary skill in the art will further recognize that the connecting member  125  also need not necessarily be a wire, and may optionally comprise an alternative structure such as a leadframe, the present invention not being limited to any particular structure for the connecting member  125 . 
     In addition to the aforementioned structural features, the receiver die assembly  100  includes an identically configured pair of connectors  140  which are in contact with the conductive member  130 , and protrude generally perpendicularly relative to the first surface  111  of the substrate  110  in the manner best shown in  FIGS. 1C and 1D . As further seen in  FIG. 1C , the connectors  140  are further positioned on the substrate  110  so as to be located in relative close proximity to respective ones of a diagonally opposed pair of the corner regions defined by the quadrangular receiver die  120 . The connectors  140  are sized and configured to facilitate the coupling of respective ones of a pair of wires  400  (shown in  FIGS. 1A and 1B ) thereto. To this end, each of the connectors  140  preferably includes a base portion  141  which is configured as a generally tubular pillar having a generally square cross-sectional configuration. In addition to the base portion  141 , each connector  140  includes a hook portion  142  which is disposed within the interior of the base portion  141 . The wires  400  which are ultimately coupled to respective ones of the connectors  140  each comprise an internal conductor  410  covered by an external sheath  420 . To facilitate its connection to a corresponding connector  140 , each wire  140  is prepared such that an end portion of the conductor  410  protrudes from one end of the corresponding sheath  420  (and is thus exposed) in the manner shown in  FIG. 1B . Each connector  140  is configured to allow the corresponding wire  400  to be inserted upwardly into the hollow interior of the base portion  141  thereof, with the exposed end portion of the conductor  410  ultimately being hung on thus electrically connected to the hook portion  142  within the interior of the base portion  141  in the manner best shown in  FIG. 1D . 
     The receiver die assembly  100  further comprises a first (lower) holder member  200  which is attached to a peripheral portion of the receiver die  120  and defines an opening  200   a  in which the active, front surface of the receiver die  120  is exposed. More particularly, the opening  200   a  of the first holder member  200  is defined by a generally quadrangular (e.g., square) peripheral wall portion  210  of the first holder member  200 . The wall portion  210  itself comprises four wall segments  210   a ,  210   b ,  210   c ,  210   d  which are arranged in a generally quadrangular pattern and collectively define the opening  200   a . In addition to the wall portion  210 , the first holder member  200  includes an opposed pair of support portions  220  which protrude laterally from respective ones of the wall segments  210   a ,  210   b  of the wall portion  210  in the manner best shown in  FIG. 4 . As best seen in  FIG. 1D , the opening  200   a  of the first holder member  200  is sized to receive and thus accommodate a lower end portion of an optical light guide  500  of the CPV module  1000 . As will be discussed in more detail below, the optical light guide  500  is coupled to the active front surface of the receiver die  120 , with the first holder member  200  being adapted to facilitate the proper alignment between the optical light guide  500  and the receiver die  120 . It is contemplated that the first holder member  200  may be made of aluminum (Al), copper (Cu), ceramic, or equivalents thereof, though the present invention is not intended to be limited to any particular material for the first holder member  200 . 
     In addition to the receiver die assembly  100  described above, the CPV module  1000  includes a heat spreader  300  which has a generally quadrangular (e.g., square) configuration. As best seen in  FIGS. 1A, 1B and 1D , the heat spreader  300  includes a generally planar first (top) surface  310  and an opposed, generally planar second (bottom) surface  320 . The heat spreader  300  also includes a peripheral side surface  300  which extends generally perpendicularly between the first and second surfaces  310 ,  320 , and includes at least four peripheral side surface segments. In addition, the heat spreader  300  includes a spaced pair of elongate wire receiving grooves  312  within the first surface  310  thereof, each of the wire receiving grooves  312  extending to respective ones of an opposed pair of the side surface segments defined by the side surface  330 . The wire receiving grooves  312  are sized and configured to accommodate portions of respective ones of the above-described wires  400 . 
     In the CPV module  1000 , the second surface  112  of the substrate  110  is attached to the first surface  310  of the heat spreader  300  through the use of an adhesive member  115 . The adhesive member  115  has a generally quadrangular (e.g., square) configuration with length and width dimensions substantially mirroring those of the substrate  110  of the receiver die assembly  100 . It is contemplated that the adhesive member  115  may be made of a silver die adhesive epoxy, thermal grease, curable thermal grease, a silicon adhesive, or equivalents thereto, though the present invention is not intended to be limited to any specific material for the adhesive member  115 . In the CPV module  1000 , the heat spreader  300  is operative to emit heat generated from the substrate  110 . To this end, it is also contemplated that the heat spreader  300  may be made of aluminum or equivalents thereto, though the present invention is not intended to be limited to any specific material for the heat spreader  300 . As will be recognized, the heat spreader  300  also serves to support the substrate  110  of the receiver die assembly  100 . 
     As indicated above, the wire receiving grooves  312  of the heat spreader  300  are adapted to receive respective ones of the wires  400 , with such wires  400  thereafter being operatively coupled to respective ones of the connectors  140  of the receiver die assembly  100  in the aforementioned manner, i.e., each of the wires  400  is upwardly advanced into the hollow interior of the base portion  141  of a corresponding connector  140 , with the exposed portion of the conductor  410  of such wire  400  being hung on the hook portion  142  of the corresponding connector  140 . As seen in  FIG. 1D , to facilitate its coupling to a corresponding connector  140  in the aforementioned manner, each wire  400  residing within a corresponding wire receiving groove  312  also passes through a respective one of a pair of openings disposed within the substrate  110 . These openings each extend between the first and second surfaces  111 ,  112  of the substrate  110 , and are aligned with the hollow interior of the base portion  141  of a respective one of the connectors  140 . As further seen in  FIG. 1D , when the wires  400  are operatively coupled to the receiver die assembly  100  through the use of respective ones of the connectors  140 , the sheath  420  of each of the wires  400  extends between the corresponding wire receiving groove  312  of the heat spreader  300  and the hook portion  142  of the corresponding connector  140 . Further, when the wires  400  are received into respective ones of the wire receiving grooves  312 , the outermost surface defined by the sheath  420  of each wire  400  is exposed in the first surface  310  of the heat spreader  300 , and extends in generally co-planar relation to the first surface  310 . However, it is contemplated that the receiving grooves  312  may be formed to have a depth such that when the wires  400  are nested therein in the aforementioned manner, the outermost surface of the sheath  420  is actually positioned lower than or is recessed relative to the first surface  310  of the heat spreader  300 , rather than extending in generally co-planar relation thereto. 
     As indicated above, the CPV module  1000  includes an optical light guide  500  which is coupled to the active front surface of the receiver die  120 . The light guide  500  is preferably formed as a pillar-shaped prism which, from the perspective shown in  FIG. 1D , has a generally quadrangular (e.g., square) first (top) surface  510 , a generally quadrangular (e.g., square) second (bottom) surface  530 , and a side surface  520  which extends between the first and second surfaces  510 ,  530 . As is most apparent from  FIG. 1B , the side surface  520  defines four separate side surface sections. Additionally, the length and width dimensions of the first surface  510  of the light guide  500  exceed those of the second surface  530  thereof, thus resulting in the side surface  520  having a downwardly tapered configured when viewed from the perspectives shown in  FIGS. 1B and 1D . In the CPV module  1000 , the second surface  530  of the light guide  500  is operatively coupled to the active top or front surface of the receiver die  120  through the use of a layer  550  of a transparent adhesive. As indicated above, the optical light guide  500  is operative to focus light incident from the sun and transmit such light to the receiver die  120 . 
     The CPV module  1000  of the present invention further comprises a generally conical second (upper) holder member  600  which effectively covers the receiver die assembly  100 , but exposes the first surface  510  of the optical light guide  500 . As seen in  FIGS. 1A, 1B and 1D , it is contemplated that the second holder member  600  may be coupled to the first surface  310  of the heat spreader  300  through the use of coupling members  645  such as screws. The second holder member  600  includes a first (top) surface  610 , a second (bottom) surface  630 , and a side wall  620  which has a generally circular cross-sectional configuration and extends between the first and second surfaces  610 ,  630 . In the second holder member  600 , the diameter of the side wall  620  at its point of transition to the second surface  630  exceeds the diameter of the side wall  620  at its point of transition to the first surface  610 . As a result, the second holder member  600  assumes the general configuration of a truncated cone. When the second holder member  600  is operatively coupled to the substrate  300  in the aforementioned manner, the first surface  510  of the optical light guide  500  is exposed in and substantially flush with the first surface  610  of the second holder member  600  in the manner shown in  FIG. 1D . As also shown in  FIG. 1D , the second holder member  600  includes a tapered inner surface  611  which defines an opening passing axially through the second holder member  600 . The inner surface  611  has a configuration which is complimentary to the side surface  520  of the optical light guide  500 . In the CPV module  1000 , the light guide  500  is nested within the opening defined by the inner surface  611  such that the first surface  510  of the light guide  500  extends in substantially flush relation to the first surface  610  of the second holder member  600  as indicated above. 
     The CPV module  1000  of the present invention further comprises a generally conical second (upper) holder member  600  which effectively covers the receiver die assembly  100 , but exposes the first surface  510  of the optical light guide  500 . As seen in  FIGS. 1A, 1B and 1D , it is contemplated that the second holder member  600  may be coupled to the first surface  310  of the heat spreader  300  through the use of coupling members  645  such as screws. The second holder member  600  includes a first (top) surface  610 , a second (bottom) surface  630 , and a side wall  620  which has a generally circular cross-sectional configuration and extends between the first and second surfaces  610 ,  630 . In the second holder member  600 , the diameter of the side wall  620  at its point of transition to the second surface  630  exceeds the diameter of the side wall  620  at its point of transition to the first surface  610 . As a result, the second holder member  600  assumes the general configuration of a truncated cone. When the second holder member  600  is operatively coupled to the substrate  300  in the aforementioned manner, the first surface  510  of the optical light guide  500  is exposed in and substantially flush with the first surface  610  of the second holder member  600  in the manner shown in  FIG. 1D . As also shown in  FIG. 1D , the second holder member  600  includes a tapered inner surface  611  which defines an opening passing axially through the second holder member  600 . The inner surface  611  has a configuration which is complementary to the side surface  520  of the optical light guide  500 . In the CPV module  1000 , the light guide  500  is nested within the opening defined by the inner surface  611  such that the first surface  510  of the light guide  500  extends in substantially flush relation to the first surface  610  of the second holder member  600  as indicated above. 
     In the CPV module  1000 , it is contemplated that a first (bottom) surface  640   a  defined by the block portion  640  may be spaced from the second surface  530  of the optical light guide  500  a distance which is 10% or less than the overall height of the optical light guide  500  between the first and second surfaces  510 ,  530  thereof. If the distance between the first surface  640   a  of the block portion  640  and the second surface  530  of the light guide  500  exceeds 10% the overall height of the optical light guide  500 , the interference preventing effect otherwise produced by the block portion  640  is reduced. 
     As is further seen in  FIG. 1D , the second holder member  600  includes an open area or gap  650  which is defined between the side wall  620  and the internal block portion  640 . Such gap  650  is partially defined by an interior surface  651  of the upper holder member  600 , such interior surface  651  facing the connectors  140  of the receiver die assembly  100  and being separated therefrom by a prescribed distance. The spacing between the interior surface  651  and the connectors  140  is adapted to prevent any interference between the wires  400  and the upper holder member  600 . It is contemplated that the single gap  650  may comprise separate gaps defined by the second holder member  600  and aligned with respective ones of the connectors  140  of the receiver die assembly  100 . 
     As previously explained, in the CPV module  1000  constructed in accordance with the present invention, the block portion  640  of the second holder member  600  is in contact with the lower portion of the side surface  520  of the optical light guide  500 . Thus, the CPV module  1000  is specifically configured to prevent the transparent adhesive layer  550  from excessively moving or migrating upwardly along the side surface  520  of the optical member  500  from the second surface  530  thereof, thereby reducing the interference between the incident light entering through the optical light guide  500  and the transparent adhesive layer  550 . This reduction in interference ultimately reduces the loss of the incident light. As a result, the CPV module  1000  provides improved generation efficiency of electrical energy from the receiver die  120  of the receiver die assembly  100  thereof. In addition, in the CPV module  1000  of the present invention, the wires  400  extend through the heat spreader  300  and the substrate  110  prior to being coupled to the connectors  140  of the receiver die assembly  100 , thereby allowing for a reduced height of each of the connectors  140  and more efficiently suppressing the interference between the wires  400  and the optical light guide  500 . This provides an improvement over those CPV module configurations wherein the wires are downwardly coupled to connectors. As a result, the CPV module  1000  can be manufactured through the implementation of an easier, more simplified manufacturing process. 
     Having thus described the structural features of the CPV module  1000 , an exemplary method of fabricating the same will now be described with specific reference to  FIGS. 5 and 6A-6D . More particularly, as set forth in  FIG. 5 , the exemplary fabrication method comprises the steps of preparing the wires  400  (S 1 ), coupling the receiver die assembly  100  to the wires  400  and heat spreader  300  (S 2 ), coupling the second holder member  600  to the heat spreader  300  (S 3 ), and coupling the optical light guide  500  to the second holder member  600  and receiver die assembly  100  (S 4 ).  FIGS. 6A-6D  provide illustrations corresponding to these particular steps, as will be discussed in more detail below. 
     Referring now to  FIG. 6A , in the initial step S 1  of the fabrication process from the CPV module  1000 , the wires  400  are advanced into respective ones of the wire receiving grooves  312  formed in the first surface  310  of the heat spreader  300  in the aforementioned manner. More particularly, as seen in  FIG. 6A , the wires  400  are prepared such that the internal conductors  400  thereof protrude from respective ones of the sheathes  420 , with the wires  400  being bent such that end portions thereof including the exposed internal conductors  410  extend generally perpendicularly relative to the first surface  310  of the heat spreader  300 . As indicated above, for those portions of the wires  400  residing within the wire receiving grooves  312 , the sheathes  420  extend in generally co-planar relation to, or are recessed relative to, the first surface  310  of the heat spreader  300 , with the wires  400  further protruding from respective ones of an opposed pair of the side surface segments of the side surface  330  of the heat spreader  300 . 
     In the next step S 2  of the fabrication process for the CPV module  1000  shown in  FIG. 6B , the fully fabricated receiver die assembly  100  is coupled to the heat spreader  300 . More particularly, the second surface  112  of the substrate  110  is coupled to the first surface  310  of the heat spreader  300  using the adhesive member  115 . Such attachment is facilitated in a manner wherein those portions of the wires  400  extending generally perpendicularly relative to the first surface  310  of the heat spreader  300  are advanced through respective ones of the aforementioned openings disposed within the substrate  110 , and (when viewed from the perspective shown in  FIG. 6B ) upwardly into the base portions  141  of respective ones of the connectors  140 . As also explained above, the exposed portions of the internal conductors  410  of the wires  400  are hung onto and thus electrically connected to the hook portions  142  of respective ones of the connectors  140 . 
     In the next step S 3  of the fabrication process for the CPV module  1000  shown in  FIG. 6C , the second holder member  600  is coupled to the first surface  310  of the heat spreader  300  in the aforementioned manner through the use of the coupling members  645 . As explained above, the second holder member  600 , when attached to the heat spreader  300 , covers the receiver die assembly  100 . However, as is apparent from  FIG. 6C , the opening of the second holder member  600  defined by the inner surface  611  thereof is aligned with and exposes the active front surface of the receiver die  120  of the receiver die assembly  100 . 
     In the final step S 4  of the fabrication process for the CPV module  1000  shown in  FIG. 6D , the optical light guide  500  is advanced into the aforementioned opening of the second holder member  600 . The advancement of the optical light guide  500  into the opening defined by the inner surface  611  results in the block portion  640  of the second holder member  600  coming into direct contact with at least the lower portion of the side surface  520  of the optical light guide  500 . The second surface  530  of the optical light guide  500  is further secured to the active front surface of the receiver die  120  through the use of the transparent adhesive layer  550 . Further, the optical light guide  500  is sized relative to the other structural features of the CPV module  1000  such that, when the second surface  530  is operatively secured to the receiver die  120  through the use of the transparent adhesive layer  550 , the first surface  510  of the optical light guide  500  extends in substantially flush or co-planar relation to the first surface  610  of the second holder member  600 . 
     Referring now to  FIG. 2 , there is shown a CPV module  2000  constructed in accordance with a second embodiment of the present invention. The CPV module  2000  has substantial structural similarity to the CPV module  1000  described above, with only the distinctions between the CPV modules  2000 ,  1000  being described below. 
     A first distinction between the CPV modules  2000 ,  1000  lies in the configuration of the receiver die assembly  1100  included in the CPV module  2000 , in comparison to the receiver die assembly  100  included in the CPV module  1000 . More particularly, the receiver die assembly  1100  does not include the first holder member  200  described above in relation to the receiver die assembly  100 . Other than for the omission of the first holder member  200 , the receiver die assembly  1100  is identically configured to the receiver die assembly  100  in all other respects. 
     The only other distinction between the CPV modules  2000 ,  1000  lies in the configuration of the second holder member  1600  of the CPV module  2000  in comparison to the second holder member  600  of the CPV module  1000 . Like the second holder member  600 , the second holder member  1600  includes a first surface  1610 , a second surface  1630 , and a sidewall  1620  which has a generally circular cross-sectional configuration and extends between the first and second surfaces  1610 ,  1630 . The second holder member  1600 , like the second holder member  600 , also has the general configuration of a truncated cone. The second holder member  1600  also includes a tapered inner surface  1611  which defines an opening passing axially through the second holder member  1600 , with the inner surface  1611  also having a configuration which is complimentary to the side surface  520  of the optical light guide  500 . As seen in  FIG. 2 , in the CPV module  2000 , the light guide  500  is nested within the opening defined by the inner surface  1611  such that the first surface  510  of the light guide  500  extends in substantially flush relation to the first surface  1610  of the second holder member  1600 . 
     Though, as in the second holder member  1600 , a portion of the inner surface  1611  is defined by an internal block portion  1640  of the second holder member  1600 , the internal block portions  1640 ,  640  of the second holder members  1600 ,  600  are not identically configured. Rather, when viewed from the perspectives shown in  FIGS. 1D and 2 , the length of the block portion  1640  of the second holder member  1600  (i.e., the distance the block portion  1640  protrudes from the interior surface  1651  of the second holder member  1600 ) exceeds the length of the block portion  640  of the second holder member  600  (i.e., the distance the block portion  640  protrudes from the interior surface  651  of the second holder member  600 ). As also in the second holder member  600 , a gap  1650  is defined between the block portion  1640  and side wall  1620  in the second holder member  1600 . 
     Thus, in the CPV module  2000  including the second holder member  1600 , the first surface  1640   a  defined by the block portion  1640  is positioned in closer proximity to the transparent adhesive layer  550 , with such closer positioning being made possible by the aforementioned omission or absence of the first holder member  200  in the receiver die assembly  1100  of the CPV module  2000 . The positioning of the block portion  1640 , and in particular the first surface  1640   a  thereof, in closer proximity to the receiver die  120  and transparent adhesive layer  550  effectively prevents the transparent adhesive layer  550  from moving or migrating excessively upwardly along the side surface  520  of the optical light guide  500 , thus providing the same operational advantages in the CPV module  2000  as described above in relation to the CPV module  1000 . Further, the omission of the first holder member  200  in the receiver die assembly  1100  effectively reduces the manufacturing cost for the CPV module  2000  while further simplifying the manufacturing process as well. Those of ordinary skill in the art will recognize that in the CPV module  2000 , the length of the block portion  1640  (i.e., the distance by which the block portion  1640  protrudes from the interior surface  1651 ) may be slightly varied from that shown in  FIG. 2  as may be needed to achieve the greatest level of prevention in relation to the loss of incident light. 
     Having thus described the structural features of the CPV module  2000  an exemplary method of fabricating the same will now be described with specific reference to  FIGS. 7 and 8 . More particularly, as set forth in  FIG. 7 , the exemplary fabrication method comprises the steps of preparing the wires  400  (S 1 ), coupling the receiver die assembly  1100  to the wires  400  and heat spreader  300  (S 2 ′), coupling the second holder member  1600  to the heat spreader  300  (S 3 ), and coupling the optical light guide  500  to the second holder member  1600  and receiver die assembly  1100  (S 4 ). The steps S 1 , S 3  and S 4  of the fabrication method for the CPV module  2000  are essentially the same as those described above in relation to the fabrication method for the CPV module  1000 . In this regard,  FIG. 8  provides an illustration corresponding to step S 2 ′ related to the fabrication process for the CPV module  2000 , such step S 2 ′ being substantially similar to step S 2  of the fabrication process for the CPV module  1000 . 
     In step S 2 ′ for the CPV module  2000  shown in  FIG. 8 , the second surface  112  of the substrate  110  of the receiver die assembly  1100  is coupled to the first surface  310  of the heat spreader  300  through the use of the adhesive member  115 . However, since the receiver die assembly  1100  is not provided with the first holder member  200  described above in relation to the receiver die assembly  100 , the receiver die assembly  1100  is able to accommodate the increased length block portion  1640  of the second holder member  1600  when the same is attached to the heat spreader  300  in step S 3  of the fabrication method for the CPV module  2000 . 
     Referring now to  FIGS. 3 and 4 , there is shown a CPV module  3000  constructed in accordance with a third embodiment of the present invention. The CPV module  3000  also has substantial structural similarity to the CPV module  1000  described above, with only the distinctions between the CPV modules  3000 ,  1000  being described below. 
     A first distinction between the CPV modules  3000 ,  1000  lies in the configuration of the receiver die assembly  2100  included in the CPV module  2000 , in comparison to the receiver die assembly  100  included in the CPV module  1000 . More particularly, the receiver die assembly  2100  is substantially identical to the receiver die assembly  100 , except that in the receiver die assembly  2100 , the peripheral wall portion  210  of the first holder member  200  is provided with a generally quadrangular (e.g., square), frame-like block member  2700 . As best shown in  FIG. 4 , the block member  2700  extends about, and protrudes inwardly at a prescribed distance from, the inner surfaces of each of the four wall segments  210   a ,  210   b ,  210   c ,  210   d  of the peripheral wall portion  210  which defines the opening  200   a  of the first holder member  200 . The block member  2700  may be formed by coating rubber or a suitable sealing agent on the inner surfaces of the four wall segments  210   a ,  210   b ,  210   c ,  210   d . As will be described in more detail below, in the CPV module  3000 , the block member  2700  performs a similar function to the block portion  640  of the second holder member  600  in the CPV module  1000 . 
     Another distinction between the CPV modules  3000 ,  1000  lies in the configuration of the second holder member  2600  of the CPV module  3000  in comparison to the second holder member  600  of the CPV module  1000 . In the CPV module  3000 , the generally conical second holder member  2600  effectively covers the receiver die assembly  200 , but exposes the first surface  510  of the optical light guide  500 . The second holder member  2600  includes a first (top) surface  2610 , a second (bottom) surface  2630 , and a side wall  2620  which has a generally circular cross-sectional configuration and extends between the first and second surfaces  2610 ,  2630 . In the second holder member  2600 , the diameter of the side wall  2620  at its point of transition to the second surface  2630  exceeds the diameter of the side wall  2620  at its point of transition to the first surface  2610 . As a result, the second holder member  2600  assumes the general configuration of a truncated cone. When the second holder member  2600  is operatively coupled to the substrate  300 , the first surface  510  of the optical light guide  500  is exposed in and substantially flush with the first surface  2610  of the second holder member  2600  in the manner shown in  FIG. 3 . 
     As also shown in  FIG. 3 , the second holder member  2600  does not include the block portion  640  described above in relation to the second holder member  600 . Rather, the second holder member  2600  includes an internal support wall  2640  having a tapered inner surface  2611  which defines an opening extending from the first surface  2610  into communication with an open interior chamber  2650  of the second holder member  2600 . The inner surface  2611  has a configuration which is complimentary to the upper portion of the side surface  520  of the optical light guide  500 . In the CPV module  3000 , the light guide  500  is nested within the opening defined by the inner surface  2611  of the support wall  2640  such that the first surface  510  of the light guide  500  extends in substantially flush relation to the first surface  2610  of the second holder member  2600  as indicated above. When viewed from the perspective shown in  FIG. 3 , the inner surface  2611  is in contact with the upper portion of the side surface  520  of the optical light guide  500 . 
     When also viewed from the perspective shown in  FIG. 3 , in the CPV module  3000 , the lower portion of the optical light guide  500  is advanced into the opening  200   a  of the first holder member  200  as a precursor to the second surface  530  being operatively coupled to the active front surface of the receiver die  120  through the use of the transparent adhesive layer  550 . The advancement of the optical light guide  500  into the opening  200   a  results in the generally quadrangular block member  2700  being firmly seated against a lower portion of the side surface  520  of the optical light guide  500 . More particularly, those segments of the block member  2700  extending along the inner surfaces of respective ones of the four wall segments  210   a ,  210   b ,  210   c ,  210   d  of the peripheral wall portion  210  are abutted against respective ones of the side surface sections defined by the side surface  520 . Like the block portion  640  described above in relation to the second holder member  600 , the block member  2700  is operative to prevent interference between the transparent adhesive layer  550  and incident light by preventing the transparent adhesive layer  550  from excessively moving or migrating upwardly along the side surface  520  of the optical light guide  500  from the second surface  530  thereof. Thus, the block member  2700  imparts the same functional advantages to the CPV module  3000  as does the block portion  640  included in the second holder member  600  of the CPV module  1000 . Further, the relatively large interior chamber  2650  defined by the second holder member  2600  in the CPV module  3000  effectively reduces any potential interference between the wires  400  and the second holder member  2600 . The substitution of the block portion  640  with the block member  2700  also allows the CPV module  3000  to be fabricated through the implementation of a simplified fabrication process. 
     Having thus described the structural features of the CPV module  3000  an exemplary method of fabricating the same will now be described with specific reference to  FIGS. 9-11 . More particularly, as set forth in  FIG. 9 , the exemplary fabrication method comprises the steps of preparing the wires  400  (S 1 ), coupling the receiver die assembly  2100  to the wires  400  and heat spreader  300  (S 2 ″), coupling the second holder member  2600  to the heat spreader  300  (S 3 ″), and coupling the optical light guide  500  to the second holder member  2600  and receiver die assembly  1100  (S 4 ). The steps S 1  and S 4  of the fabrication method for the CPV module  3000  are essentially the same as those described above in relation to the fabrication method for the CPV module  1000 . In this regard,  FIG. 10  provides an illustration corresponding to step S 2 ″ related to the fabrication process for the CPV module  3000 , such step S 2 ″ being substantially similar to step S 2  of the fabrication process for the CPV module  1000 . Similarly,  FIG. 11  provides an illustration corresponding to step S 3 ″ related to the fabrication process for the CPV module  3000 , such step S 3 ″ being substantially similar to step S 3  of the fabrication process for the CPV module  1000 . 
     In step S 2 ″ for the CPV module  3000  shown in  FIG. 10 , the second surface  112  of the substrate  110  of the receiver die assembly  2100  is coupled to the first surface  310  of the heat spreader  300  through the use of the adhesive member  115 . However, as indicated above, the receiver die assembly  2100  is formed so as to include the block member  2700  upon the inner surfaces of each of the four wall segments  210   a ,  210   b ,  210   c ,  210   d  of the peripheral wall portion  210 . 
     In step S 3 ″ for the CPV module  3000  shown in  FIG. 11 , the second holder member  2600 , having a configuration which differs from the second holder member  600  as described above, is coupled to the first surface  310  of the heat spreader  300 . The second holder member  2600 , when attached to the heat spreader  300 , covers the receiver die assembly  2100 . However, as is apparent from  FIG. 11 , the opening of the second holder member  2600  defined by the inner surface  2611  of the support wall  2640  thereof is aligned with and exposes the active front surface of the receiver die  120  of the receiver die assembly  2100 . 
     This disclosure provides exemplary embodiments of the present invention. The scope of the present invention is not limited by these exemplary embodiments. Numerous variations, whether explicitly provided for by the specification or implied by the specification, such as variations in structure, dimension, type of material and manufacturing process may be implemented by one of skill in the art in view of this disclosure.