Stacking circuit elements
View Patent ↗A method of stacking dice in an electronic circuit includes controlling a size of a hole made in a connection pad on each die of said dice to selectively provide an electrical connection to a particular die in the stack. Additionally, a method of stacking dice in an electronic circuit includes forming holes in each of the dice, and providing electrical connection material selectively at some of the holes to provide for selective electrical connections among the dice. A stack of dice in an electronic circuit includes a number of dice stacked on top of each other, each die in the stack having one or more holes therein, conductive material extending through the holes and making electrical connection between one or more of the dice in the stack and the electronic circuit. An implantable stimulator with a stack of pulse generator integrated circuits (ICs) includes a number of pulse generator ICs stacked on top of each other, each IC having a number of holes formed therein, wherein the holes are aligned, and conductive material extending through the holes and making electrical connection between one or more of said ICs in the stack and an electronic circuit of the stimulator.
1. A method of stacking dice in an electronic circuit said method comprising:
controlling a size of a hole made in a connection pad on each die of said dice to selectively provide an electrical connection to a particular die in the stack;
drilling a first hole in a first connection pad of a first die, said first hole being smaller than said first connection pad; and
drilling a second hole in a second connection pad of a second die, said second hole being larger than and removing said second connection pad.
2. The method of claim 1 , further comprising:
stacking said first and second dice with said first and second holes aligned;
placing conductive material through said first and second holes, said conductive material making an electrical connection to said first connection pad, but not to said second connection pad.
3. The method of claim 2 , wherein said conductive material comprises a conductive epoxy.
4. The method of claim 1 , wherein said drilling is preformed with a laser.
5. A method of stacking dice in an electronic circuit, said method comprising:
forming holes in each of said dice;
providing electrical connection material selectively at some of said holes to provide for selective electrical connections among said dice;
drilling a first hole in a first connection pad of a first die, said first hole being smaller than said first connection pad; and
drilling a second hole in a second connection pad of a second die, said second hole being larger than and removing said second connection pad.
6. The method of claim 5 , further comprising:
stacking said first and second dice with said first and second holes aligned;
placing conductive material through said first and second holes, said conductive material making an electrical connection to said first connection pad, but not to said second connection pad.
7. The method of claim 6 , wherein said conductive material comprises a conductive epoxy.