3D IC Integration Technology:
The ever-growing demand for more functionality within a single chip needs a paradigm shift away from current planar integration (2D IC) technology which is facing several fundamental limits. The key, which, holds the future of dramatically enhanced chip performance is the three-dimensional integrated circuit (3D IC) technology.However, before it can be realized, several technological and design challenges are to be addressed. Specifically, low temperature – low-pressure Cu-Cu bonding is a technological bottleneck which stymies the realization of 3D IC.
Prof.Singh quickly realized and systematically studied the root cause of ways to circumvent this problem to produce the technological breakthrough. To this end, Prof. Singh used a customized CMOS dual damascene compatible metal alloy to generate desirable surface characteristics such as reduced surface roughness, absence of oxide layer, and
enhanced orientation of lattice plane resulting in an unprecedented, high quality, Cu-Cu thermocompression bonding at 140 ˚C at a nominal contact force of 4 bars . Prof. Singh further improved the efficiency of this process by painstakingly engineering the surface stress features, which resulted in sub 100 ˚C Cu-Cu bonding reported first time .
This work has been published in more than 20 highly reputed journals and conferences along with two patents which have been cited more than 100 times in the last five years.
Notably, Prof. Singh has completed licensing agreement and technology transfer to a company named Solid Block Pvt. limited.
Additionally, Prof. Singh’s group has been working on several applications of 3D IC integration, such as the development of 3D Resonator & 3D CMUT. His group has successfully fabricated the world’s first 3D patch antenna on Si using thermo-compression bonding technique. As an extended application of 3D integration, Prof. Singh has also worked on hermitical sealing methods for developing microfluidic devices and this work gets the best paper award in IEEE IWPSD 2018 conference.
