Method of making a semiconductor chip assembly with a base heat spreader and a cavity in the base

Abstract

A method of making a semiconductor chip assembly includes providing a post and a base, mounting an adhesive on the base including inserting the post into an opening in the adhesive, mounting a substrate on the adhesive including aligning the post with an aperture in the substrate, then flowing the adhesive into and upward in a gap located in the aperture between the post and the substrate, solidifying the adhesive, then etching the post and the base to form a cavity that extends through the adhesive into the base, then mounting a semiconductor device on the base, wherein a heat spreader includes the base and the semiconductor device extends into the cavity, electrically connecting the semiconductor device to the substrate and thermally connecting the semiconductor device to the heat spreader.

1 - 35 . (canceled) 
   
   
       36 . A method of making a semiconductor chip assembly, comprising:
 providing a post, a base, an adhesive and a conductive layer, wherein
 the post is adjacent to the base, extends above the base in an upward direction, extends into an opening in the adhesive and is aligned with an aperture in the conductive layer, 
 the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, 
 the adhesive is mounted on and extends above the base, is sandwiched between the base and the conductive layer and is non-solidified, and 
 the conductive layer is mounted on and extends above the adhesive; then 
   flowing the adhesive into and upward in a gap located in the aperture between the post and the conductive layer;   solidifying the adhesive;   providing a conductive trace that includes a pad, a terminal and a selected portion of the conductive layer;   etching the post and the base, thereby forming a cavity that extends through the adhesive into the base and faces in the upward direction; then   mounting a semiconductor device on the base, wherein a heat spreader includes the base and the semiconductor device extends into the cavity;   electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and   thermally connecting the semiconductor device to the base.   
   
   
       37 . The method of  claim 36 , wherein providing the post and the base includes:
 providing a metal plate;   forming an etch mask on the metal plate that selectively exposes the metal plate;   etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and then   removing the etch mask, wherein the post includes an unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the post and the recess.   
   
   
       38 . The method of  claim 36 , wherein:
 providing the adhesive includes providing a prepreg with uncured epoxy;   flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and   solidifying the adhesive includes curing the uncured epoxy.   
   
   
       39 . The method of  claim 36 , wherein flowing the adhesive includes filling the gap with the adhesive. 
   
   
       40 . The method of  claim 36 , wherein mounting the conductive layer includes mounting the conductive layer alone on the adhesive. 
   
   
       41 . The method of  claim 36 , wherein mounting the conductive layer includes mounting the conductive layer and a dielectric layer on the adhesive. 
   
   
       42 . The method of  claim 36 , wherein providing the pad includes removing selected portions of the conductive layer after solidifying the adhesive. 
   
   
       43 . The method of  claim 36 , wherein providing the pad and the terminal includes removing selected portions of the conductive layer after solidifying the adhesive. 
   
   
       44 . The method of  claim 43 , wherein forming the cavity includes etching the post after removing the selected portions of the conductive layer. 
   
   
       45 . The method of  claim 36 , wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the base, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the base. 
   
   
       46 . A method of making a semiconductor chip assembly, comprising:
 providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, and the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions;   providing an adhesive, wherein an opening extends through the adhesive;   providing a conductive layer, wherein an aperture extends through the conductive layer;   mounting the adhesive on the base, including inserting the post into the opening, wherein the adhesive extends above the base and the post extends into the opening;   mounting the conductive layer on the adhesive, including aligning the post with the aperture, wherein the conductive layer extends above the adhesive and the adhesive is sandwiched between the base and the conductive layer and is non-solidified; then applying heat to melt the adhesive;   moving the base and the conductive layer towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in a gap located in the aperture between the post and the conductive layer;   applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the conductive layer; then   providing a conductive trace that includes a pad, a terminal and a routing line, wherein the pad, the terminal and the routing line include selected portions of the conductive layer and an electrically conductive path between the pad and the terminal includes the routing line;   etching the post and the base, thereby forming a cavity that extends through the adhesive into the base and faces in the upward direction; then   mounting a semiconductor device on the base, wherein a heat spreader includes the base and the semiconductor device extends into the cavity;   electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and   thermally connecting the semiconductor device to the base.   
   
   
       47 . The method of  claim 46 , wherein providing the post and the base includes:
 providing a metal plate;   forming an etch mask on the metal plate that selectively exposes the metal plate;   etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and then   removing the etch mask, wherein the post includes an unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the post and the recess.   
   
   
       48 . The method of  claim 46 , wherein:
 providing the adhesive includes providing a prepreg with uncured epoxy;   flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and   solidifying the adhesive includes curing the uncured epoxy.   
   
   
       49 . The method of  claim 46 , wherein mounting the conductive layer includes mounting the conductive layer alone on the adhesive. 
   
   
       50 . The method of  claim 46 , wherein mounting the conductive layer includes mounting the conductive layer and a dielectric layer on the adhesive. 
   
   
       51 . The method of  claim 46 , wherein forming the cavity includes etching the post after removing the selected portions of the conductive layer. 
   
   
       52 . The method of  claim 46 , wherein forming the cavity includes etching the post, thereby removing the post. 
   
   
       53 . The method of  claim 46 , wherein providing the pad, the terminal and the routing line includes removing selected portions of the conductive layer using an etch mask that defines the pad, the terminal and the routing line. 
   
   
       54 . The method of  claim 46 , wherein providing the pad, the terminal and the routing line includes:
 grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction; and then   removing selected portions of the conductive layer using an etch mask that defines the pad, the terminal and the routing line.   
   
   
       55 . The method of  claim 46 , wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the base, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the base. 
   
   
       56 . A method of making a semiconductor chip assembly, comprising:
 providing a post, a base, an adhesive and a substrate, wherein
 the substrate includes a conductive layer and a dielectric layer, 
 the post is adjacent to the base, extends above the base in an upward direction, extends through an opening in the adhesive and extends into an aperture in the substrate, 
 the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions, 
 the adhesive is mounted on and extends above the base, is sandwiched between the base and the substrate and is non-solidified, 
 the substrate is mounted on and extends above the adhesive, and the conductive layer extends above the dielectric layer, and 
 a gap is located in the aperture between the post and the substrate; then flowing the adhesive into and upward in the gap; 
   solidifying the adhesive; then   etching the post and the base, thereby forming a cavity that extends through the adhesive into the base and faces in the upward direction; then   mounting a semiconductor device on the base, wherein a heat spreader includes the base, the semiconductor device extends into the cavity, a conductive trace includes a pad, a terminal and a selected portion of the conductive layer and the pad is electrically connected to the terminal;   electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and   thermally connecting the semiconductor device to the base.   
   
   
       57 . The method of  claim 56 , wherein providing the post and the base includes:
 providing a metal plate;   forming an etch mask on the metal plate that selectively exposes the metal plate;   etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and then   removing the etch mask, wherein the post includes an unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the post and the recess.   
   
   
       58 . The method of  claim 56 , wherein:
 providing the adhesive includes providing a prepreg with uncured epoxy;   flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and   solidifying the adhesive includes curing the uncured epoxy.   
   
   
       59 . The method of  claim 56 , wherein flowing the adhesive includes filling the gap with the adhesive. 
   
   
       60 . The method of  claim 56 , wherein forming the cavity includes etching the post after removing selected portions of the conductive layer. 
   
   
       61 . The method of  claim 56 , wherein forming the cavity includes etching the post, thereby removing the post. 
   
   
       62 . The method of  claim 56 , wherein providing the pad and the terminal includes removing selected portions of the conductive layer after solidifying the adhesive. 
   
   
       63 . The method of  claim 56 , wherein providing the pad and the terminal includes:
 grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction; and then   removing selected portions of the conductive layer using an etch mask that defines the pad and the terminal.   
   
   
       64 . The method of  claim 56 , wherein providing the terminal includes removing selected portions of the base after solidifying the adhesive. 
   
   
       65 . The method of  claim 56 , wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the base, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the base. 
   
   
       66 . A method of making a semiconductor chip assembly, comprising:
 providing a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, and the base extends below the post in a downward direction opposite the upward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions;   providing an adhesive, wherein an opening extends through the adhesive;   providing a substrate that includes a conductive layer and a dielectric layer, wherein an aperture extends through the substrate;   mounting the adhesive on the base, including inserting the post through the opening, wherein the adhesive extends above the base and the post extends through the opening;   mounting the substrate on the adhesive, including inserting the post into the aperture, wherein the substrate extends above the adhesive, the conductive layer extends above the dielectric layer, the post extends through the opening into the aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, and a gap is located in the aperture between the post and the substrate; then   applying heat to melt the adhesive;   moving the base and the substrate towards one another, thereby moving the post upward in the aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gap and the post and the molten adhesive extend above the dielectric layer;   applying heat to solidify the molten adhesive, thereby mechanically attaching the post and the base to the substrate; then   etching the post and the base, thereby forming a cavity that extends through the adhesive into the base and faces in the upward direction and removing the post; then   mounting a semiconductor device on the base, wherein a heat spreader includes the base, the semiconductor device is located within the cavity, a conductive trace includes a pad, a terminal and a selected portion of the conductive layer and the pad is electrically connected to the terminal;   electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and   thermally connecting the semiconductor device to the base.   
   
   
       67 . The method of  claim 66 , wherein providing the post and the base includes:
 providing a metal plate;   forming an etch mask on the metal plate that selectively exposes the metal plate;   etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and then   removing the etch mask, wherein the post includes an unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the post and the recess.   
   
   
       68 . The method of  claim 66 , wherein:
 providing the adhesive includes providing a prepreg with uncured epoxy;   flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and   solidifying the adhesive includes curing the uncured epoxy.   
   
   
       69 . The method of  claim 66 , wherein providing the pad and the terminal includes removing selected portions of the conductive layer using an etch mask that defines the pad and the terminal after solidifying the adhesive. 
   
   
       70 . The method of  claim 66 , wherein providing the pad and the terminal includes:
 grinding the post, the adhesive and the conductive layer such that the post, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction; and then   removing selected portions of the conductive layer using an etch mask that defines the pad and the terminal.