Electrical package employing segmented connector and solder joint
View Patent ↗An electronic package is provided having a connector and a solder joint that is less susceptible to thermal fatigue. The package includes a die including a first electrically conductive connecting surface having a first coefficient of thermal expansion and a substrate including electrical circuitry and a second electrically conductive connecting surface having a second coefficient of thermal expansion. The package further includes a solder joint connecting the first connecting surface to the second connecting surface. One of the first and second connecting surfaces includes a plurality of pads spaced from each other. By employing an electrical connection having a plurality of pads spaced from each other, the solder joint is relieved to reduce fatigue caused by thermal cycling.
1. A method of forming an electrical connection between an electrically conductive contact surface of a die and a substrate, said method comprising the steps of:
providing a die having an electrically conductive contact surface;
forming a carrier defining multiple regions isolated from each other;
forming a plurality of electrically conductive contact pads in the multiple regions of the carrier, wherein the plurality of electrically conductive pads form an electrical connecting terminal;
disposing a solder material between the plurality of contact pads and the electrically conductive contact surface of the die; and
curing the solder so as to form a connection between the electrically conductive contact surface of the die and the individual contact pads.
2. The method as defined in claim 1 , wherein the step of forming the plurality of electrically conductive contact pads comprises forming an array of copper regions.
3. The method as defined in claim 1 , wherein the step of providing a die comprises providing a die comprising silicon.
4. The method as defined in claim 1 , wherein the step of forming a carrier comprises forming a carrier comprised of liquid crystal polymer plastic material.
5. The method as defined in claim 1 , wherein the step of curing the solder comprises heating a sheet of solder to an elevated temperature to reflow the solder sheet and cooling the reflowed solder.
6. The method as defined in claim 1 , wherein the step of forming a carrier comprises forming dividers that define and isolate the multiple regions.
7. The method as defined in claim 1 , wherein the die comprises a field effect transistor.
8. The method as defined in claim 1 , wherein the die comprises a first material exhibiting a first coefficient of thermal expansion and the electrical connecting terminal comprises a material exhibiting a second coefficient of thermal expansion that is different than the first coefficient of thermal expansion.
9. The method as defined in claim 8 , wherein the carrier comprises a third material exhibiting a third coefficient of thermal expansion that is substantially equal to the second coefficient of thermal expansion.
10. The method as defined in claim 1 further comprising the step of disposing a heat sink in thermal relationship with the electrically conductive contact pads.
11. A method of forming an electrical connection between a die and a substrate, said method comprising the steps of:
providing a die having an electrically conductive contact surface and comprising a first material exhibiting a first coefficient of thermal expansion;
forming a carrier defining multiple regions isolated from each other;
forming an electrical connecting terminal having a plurality of electrically conductive contact pads disposed in the multiple regions of the carrier, said electrical connecting terminal comprising a second material exhibiting a second coefficient of thermal expansion that is different than the first coefficient of thermal expansion;
disposing a solder material between the electrical connecting terminal and the electrically conductive contact surface of the die; and
curing the solder to form a connection between the electrical conductive contact surface of the die and the electrical connecting terminal.
12. The method as defined in claim 11 , wherein the step of forming the electrical connecting terminal comprises forming a plurality of copper pads.
13. The method as defined in claim 11 , wherein the step of forming the carrier comprises forming dividers that define and isolate the multiple regions.
14. The method as defined in claim 11 , wherein the carrier comprises a third material exhibiting a third coefficient of thermal expansion that is substantially equal to the second coefficient of thermal expansion.