IBM and 3M Herald New Era of 3D Electronics

IBM and 3M have partnered to pioneer a revolutionary new electronics technology that stacks semiconductor microchips into 3D packages that are 1,000 times more powerful than current devices.

State-of-the-art electronic devices such as touch-screen tablets and smartphones are thin because all of their circuitry is cast onto flat, planar semiconductor microchips that are laid out side by side, then interconnected with overlaid patterns of flat metal wires printed on circuit boards. But by taking those same chips and stacking them on top of each other, they can be interconnected by shorter wires that are faster, use less space and consume less power.

IBM and 3M are developing a new type of adhesive (blue) that can glue together up to 100 microchips into stacks of semiconductors that realize 3D electronics 1,000 times more powerful than today's flat, planar chips. (Source: IBM)

"We believe we can advance the state-of-art in packaging and create a new class of semiconductors that offer more speed and capabilities while [keeping] power usage low—[all] key requirements for many manufacturers, especially for makers of tablets and smartphones," said IBM Vice President of Research Bernard Meyerson.

3D microchips have been on the drawing board for years, but the main problem has been keeping the chips on the inside of the stack cool. Today's flat printed circuit boards allow each planar chip to dissipate heat into the air, but stacked microchips instead heat each other. 3M's job will be making an adhesive that solves this problem by conducting heat away from the interior of chip stacks.

If 3M and IBM can solve the heat problem, they will be able to put a stack of memory chips on top of processor chips and then put an input-output (I/O) networking chip on the bottom of the stack where connections are made to the outside world. The resulting electronic devices will lose their large, flat form factor in exchange for small, compact cubic shapes that are easier to power and less affected by electromagnetic noise.

3M's thermally conductive adhesive will use innovative nanoscale structures that pump heat away from the most sensitive interior circuits. Since microchips are fabricated on wafers that hold hundreds of identical copies, 3M's adhesive can be coated on an entire wafer. Each successive wafer will be "glued" with the adhesive to the next one on top of it. Finally, after the 100th wafer is glued to the top, the entire stack of wafers would then be sawed into complete 3D cube-shaped electronic devices.

"We are very excited to be an integral part of the movement to build such revolutionary 3D packaging," said Herve Gindre, division vice president at 3M Electronics Markets Materials Division.

3M lists adhesives as the first of its 46 core technologies, along with connecting devices, converting, extruding, heat shrinking, metallization, precision coating, rubber molding, thermoplastic molding, web handling and 36 more.