SEMICONDUCTOR PACKAGE INHIBITING VISCOUS MATERIAL SPREAD
A semiconductor package includes spread inhibiting structure to constrain the movement of viscous material during fabrication. In some embodiments, the spread inhibiting structure comprises a recess in an underside of a package lid overlying the die. According to other embodiments, the spread inhibiting structure comprises polymer disposed on the lid underside proximate to a side of the packaged die. According to still other embodiments, the spread inhibiting structure comprises a polymer disposed around the top of the die to serve as a dam and contain spreading. In some embodiments, the viscous material may be a Thermal Integration Material (TIM) in an uncured state, and the polymer may be the TIM in a cured state.
1 . A method comprising:
dispensing a viscous material onto a top surface of a semiconductor die supported on a substrate;
pressing a package lid onto the viscous material; and
inhibiting a lateral spread of the viscous material with a structure.
2 . The method of claim 1 wherein the viscous material comprises uncured Thermal Interface Material (TIM).
3 . The method of claim 1 wherein the structure comprises a recess in the package lid.
4 . The method of claim 3 wherein the recess comprises a first depth and further comprises a moat having a second depth.
5 . The method of claim 1 wherein the structure comprises a polymer stopper in contact with the package lid.
6 . The method of claim 1 wherein the structure comprises a polymer dam in contact with the top surface.
7 . The method of claim 6 wherein:
the viscous material comprises uncured Thermal Interface Material (TIM); and
the polymer dam comprises cured TIM.
8 . The method of claim 1 further comprising:
applying energy to the viscous material through the package lid.
9 . The method of claim 8 wherein the energy comprises thermal energy.
10 . The method of claim 8 wherein the energy comprises radiation.
11 . An apparatus comprising:
a package lid having a spread inhibitor structure disposed proximate to an expected location of a side of a die.
12 . The apparatus of claim 11 wherein the spread inhibitor structure comprises a recess of a first depth in the package lid.
13 . The apparatus of claim 12 wherein the recess further comprises a moat having a second depth.
14 . The apparatus of claim 11 wherein the spread inhibitor structure comprises a polymer stopper.
15 . The apparatus of claim 11 further comprising:
a polymer in contact with the spread inhibitor structure; and
a package lid in contact with the polymer.
16 . The apparatus of claim 15 wherein the polymer comprises a cured Thermal Interface Material (TIM).
17 . An apparatus comprising:
a die having a top surface and supported on a substrate; and
a spread inhibitor structure disposed on the top surface proximate to a side of the die.
18 . The apparatus of claim 17 wherein the spread inhibitor structure comprises a polymer dam.
19 . The apparatus of claim 18 wherein the polymer dam comprises cured Thermal Interface Material (TIM).
20 . The apparatus of claim 18 further comprising:
Thermal Interface Material (TIM) overlying the die and in contact with the polymer dam; and
a package lid in contact with the TIM.