Power module package having excellent heat sink emission capability and method for manufacturing the same

Abstract

A power module package includes a power circuit element, a control circuit element, a lead frame, an aluminum oxide substrate having a heat sink and an insulation layer, and a sealing resin. The control circuit element is electrically connected with the power circuit element to control chips within the power circuit element. The lead frame has external connection terminal leads in its edge and has a first surface to which the power circuit element and the control circuit element are attached and a second surface which is used as a heat transmission path. The heat sink is a plate made of metal such as aluminum and the electrical insulation layer is formed at least on an upper surface of the heat sink and made of aluminum oxide. The electrical insulation layer may be formed over an entire surface of the heat sink. Here, the insulation layer is attached to the second surface by an adhesive, on a region below where the power circuit element is attached, to the first surface of the lead frame. In addition, the sealing resin encloses the power circuit element and the control circuit element, the lead frame, and the metal oxide substrate and exposes the external connection terminals of the lead frame.

1 . A power module package comprising: 
 a power circuit element having one or more power semiconductor devices;    a control circuit element electrically connected with the power circuit element, for controlling the power semiconductor devices within the power circuit element;    a lead frame having external connection terminal leads with inner ends and outer ends and having a first surface to which the power circuit element and the control circuit element are attached and having a second surface opposite the first surface;    a metal/metal oxide substrate having a heat sink of a plate of metal and an electrical insulation layer formed at least on an upper surface of the metal plate and comprising an oxide of the metal, the electrical insulation layer being attached to part or all of a region of the second surface that corresponds to a region on the first surface where the power circuit element is attached; and    an encapsulating resin for enclosing the power circuit element, the control circuit element, the lead frame, and the metal oxide substrate, and outer end of external connection terminal leads of the lead frame.    
   
   
       2 . The power module package of  claim 1 , wherein the metal is aluminum or aluminum alloy.  
   
   
       3 . The power module package of  claim 1 , wherein further comprising an adhesive for attaching the insulation layer to the lead frame wherein said adhesive is an epoxy adhesive or a silicone elastomer adhesive.  
   
   
       4 . The power module package of  claim 3 , wherein the adhesive comprises a filler having a relatively high thermal conductivity and an electric insulation property.  
   
   
       5 . The power module package of  claim 4 , wherein the filler is a nitride, an aluminum oxide, a beryllium oxide, a silicon oxide or a compound of these oxides.  
   
   
       6 . The power module package of  claim 1 , wherein the lead frame further comprises a down-set die pad and the power circuit element and the insulation layer are attached to the down-set die pad.  
   
   
       7 . The power module package of  claim 1 , wherein the insulation layer is formed on a front side of the heat sink.  
   
   
       8 . The power module package of  claim 1 , wherein the encapsulating resin exposes a rear surface of the metal/metal oxide substrate.  
   
   
       9 . A power module package comprising: 
 a metal/metal oxide substrate having a heat sink of a plate of metal and an electrical insulation layer formed at least on an upper surface of the metal plate and made of an oxide of the metal;    an upper wiring layer having a wiring pattern and directly attached to the surface of the insulation layer;    external connection terminal leads having one set of ends connected to an edge of the wiring pattern of the upper wiring layer;    a power circuit element attached to the upper wiring layer and adjacent the external connection terminals and electrically connected with the external connection terminal leads through the wiring pattern;    a control circuit element attached to the upper wiring layer and electrically connected with the power circuit element and the external connection terminal leads through the wiring pattern, for controlling chips within the power circuit element; and    an encapsulating resin for enclosing the power circuit element, the control circuit element, the upper wiring layer, the metal oxide substrate, and the external connection terminals and exposing outer ends of the external connection terminal leads.    
   
   
       10 . The power module package of  claim 9 , wherein the metal is aluminum or aluminum alloy or silicon.  
   
   
       11 . The power module package of  claim 9 , wherein the power circuit element comprises: 
 a power circuit chip attached to a surface of the upper wiring layer; and    a wire for electrically connecting the power circuit chip with the wiring pattern.    
   
   
       12 . The power module package of  claim 9 , wherein the control circuit element comprises: 
 a control chip attached to a surface of the upper wiring layer; and    a wire for electrically connecting the control circuit chip with the wiring pattern.    
   
   
       13 . The power module package of  claim 9 , wherein the wiring pattern comprises copper or copper alloy.  
   
   
       14 . The power module package of  claim 13 , wherein the wiring pattern comprises Cu/Ni, Cu/Au, Cu/Au/Ni.  
   
   
       15 . A power module package comprising: 
 a metal/metal oxide substrate having an electrical insulation layer made of an oxidized metal plate, a plurality of vias made of non-oxidized metal in said substrate and formed within the electrical insulation layer, for passing through the electrical insulation layer, a first surface, and a second surface;    a first wiring layer having a first wiring pattern connected to first ends of said vias and directly attached to the first surface of the metal oxide substrate;    a second wiring layer having a second wiring pattern connected to second ends of said vias and directly attached to the second surface of the metal oxide substrate;    external connection terminal leads each having one end connected to an edge of the first wiring pattern of the first wiring layer;    a power circuit element attached to a surface of the second wiring layer and electrically connected with one or more vias through the second wiring pattern;    a control circuit element attached to a surface of the first wiring layer between the external connection terminals and electrically connected with one or more vias and the external connection terminals through the first wiring pattern, for controlling chips within the power circuit element; and    an encapsulating resin for enclosing the power circuit element, the control circuit element, the first wiring layer, the second wiring layer, the metal oxide substrate, and the external connection terminals and exposing the other end of the external connection terminals.    
   
   
       16 . A power module package comprising: 
 a metal/metal oxide substrate having an electrical insulation layer made of an oxide of a plate of metal, a plurality of vias made of non-oxidized metal and formed within the electrical insulation layer, for passing through the electrical insulation layer, a first surface, and a second surface;    a first wiring layer having a first wiring pattern connected to first ends of said vias and directly attached to the first surface of the metal oxide substrate;    a second wiring layer having a second wiring pattern connected to second ends of said vias and directly attached to the second surface of the metal oxide substrate;    external connection terminal leads each having one end connected to an edge of the first wiring pattern of the first wiring layer;    a power circuit element attached to a surface of the second wiring layer and electrically connected with one or more vias through the second wiring pattern;    a control circuit element attached to a surface of the first wiring layer between the external connection terminal leads and electrically connected with the vias and the external connection terminals through the first wiring pattern, for controlling chips within the power circuit element; and    an encapsulating resin for enclosing the power circuit element, the control circuit element, the first wiring layer, the second wiring layer, the metal oxide substrate, and the external connection terminals and exposing the other end of the external connection terminals and part of a surface of the electrical insulation layer.    
   
   
       17 . A power module package comprising: 
 a metal/metal oxide substrate having a heat sink of a plate of metal and an electrical insulation layer formed at least on an upper surface of the heat sink and made of an oxide of the metal;    a case having sidewalls whose bottoms are attached to an edge of the metal oxide substrate and a cap connected with the sidewalls, for confining a predetermined space between the sidewalls;    an upper wiring layer having a wiring pattern and directly attached to an upper surface of the electrical insulation layer between the sidewalls;    external connection terminal leads, each with one end connected with the wiring pattern of the upper wiring layer and whose other end is outside of the case;    a power circuit element attached to a surface of the upper wiring layer and electrically connected with the external connection terminal leads through the wiring pattern;    a control circuit element attached to a surface of the upper wiring layer and electrically connected with the power circuit element and the external connection terminal leads through the wiring pattern, for controlling chips within the power circuit element; and    a silicone resin for filling a space of the case to seal up the power circuit element, the control circuit element, and the upper wiring layer.    
   
   
       18 . A power module package comprising: 
 a metal/metal oxide substrate having an electrical insulation layer made of an oxide of a plate of metal, a plurality of vias made of the metal plate and formed within the electrical insulation layer, for passing through the electrical insulation layer, a first surface, and a second surface;    a wiring pattern formed on the first surface of the metal/metal oxide substrate so as to be connected with first ends of the vias;    an external connection pad formed on the second surface of the metal oxide substrate so as to be connected with the second ends of the vias;    a semiconductor element electrically connected with the wiring pattern through a contact bump and including a semiconductor chip mounted on the first surface of the metal oxide substrate; and    an encapsulating resin formed on the first surface of the metal/metal oxide substrate so as to enclose the power chip and to expose the second surface of the metal/metal oxide substrate.    
   
   
       19 . A method for manufacturing a power module package comprising: 
 attaching a metal/metal oxide substrate to a lead frame having external connection terminal leads at its edge, wherein said substrate comprises a heat sink of a plate of metal and an electrical insulation layer formed at least on an upper surface of the heat sink and made of an oxide of the metal;    attaching a power circuit chip and a control circuit chip on a first surface of the lead frame;    attaching the lead frame to the metal oxide substrate so that the insulation layer is on a region of a second surface that corresponds to superior region on the first surface where the power circuit element is attached;    connecting the power circuit chip with the control circuit chip using the lead frame by performing a wire-bonding; and    enclosing the power circuit element, the control circuit element, the lead frame, and the metal oxide substrate and sealing up those elements using an encapsulating resin so as to expose external connection terminal leads of the lead frame.    
   
   
       20 . The method of  claim 19 , wherein the attaching the lead frame to the metal oxide substrate and the wire-bonding can be performed in a reverse order.  
   
   
       21 . The method of  claim 19 , wherein an aluminum wire is used to wire bond the power circuit chip and a gold wire is used to wire bond the control circuit chip.  
   
   
       22 . The method of  claim 21 , wherein the gold wire bonding is performed after the aluminum wire bonding is performed.  
   
   
       23 . The method of  claim 19 , wherein the adhesive for attaching the lead frame to the insulation layer is an epoxy adhesive or a silicone elastomer adhesive.  
   
   
       24 . The method of  claim 23 , wherein the adhesive comprises a filler having an excellent thermal conductivity and an electric insulation property.  
   
   
       25 . The method of  claim 24 , wherein the filler is a nitride, an aluminum oxide, a beryllium oxide, a silicon oxide or a compound of these oxides.  
   
   
       26 . A method for manufacturing a power module package comprising: 
 preparing a metal/metal oxide substrate including a heat sink of a plate made of metal and an electrical insulation layer formed at least on an upper surface of the heat sink and made of an oxide of the metal;    directly attaching an upper wiring layer having a wiring pattern on an upper surface of the electrical insulation layer;    attaching one end of external connection terminal leads to an edge of the wiring pattern of the upper wiring layer;    attaching a power circuit chip and a control circuit chip to the upper wiring layer;    connecting the power circuit chip with the control circuit chip through the wiring pattern by performing a wire-bonding; and    enclosing the power circuit element, the control circuit element, the upper wiring layer, the metal oxide substrate, and one end of the external connection terminals and sealing up these elements using a sealing resin so as to expose the other end of the external connection terminals.