A brief history into photonics might suggest that the sub-discipline of nanophotonics still quiet an untapped market with much potential to be harnessed. A countable number of data points fill the the timeline from 1909 to the present. Inspiring the question that motivated this paper, why are there so few milestone moments in photonics over such a long period of time? Ultimately this question resulted in our review of nanophotonics integration with CMOS integrated circuits in response to Moore’s Law. Therefore, in this review we present our review of the modules in CMOS IC that are causing the slow down in Moore’s law, the nanophotonic analogs that may be viable replacements, and the breakthroughs in nanophotonics that have enabled these technological advancements
Sommerfeld, in 1909, proposed a phenomenon now known as surface plasmonic polaritons –referring to a particular frequency dependent diffusion response of metal material below the material’s plasma frequency. Where plasma frequency is a tunable parameter as it is proportional to a material’s electron density and dielectric function. In addition, the modal size on the x-axis is also become a tuned parameter of the material. So the obvious question to ask is what enabled such rapid improvements as sited in figure 2 and figure 3. The answer is in figure 4. To stay on pace with decreasing feature sizes of CMOS IC it became obvious that traditional noble metals were limited in applications of nanophotonic waveguides. In particular, their inability to be used as thin films due to their high surface energy and the difficulty incorporating them with existing CMOS processing step of etching. Therefore, alternative materials have been found to achieve impressive results on the order of macroscopic optical fiber waveguies. One of the most recent innovations in CMOS compatible nanophotonic waveguides, occurred in 2014, and involves the transition metal nitride molecule titanium nitride (TiN) and the dielectric silicon nitride (Si3N4). The resulting combinations was a tuned material much in the way one would tune an antenna using inductors and capacitors in analog integrated circuit design. It is among the lowest loss materials for either noble gas metals or alternative metals at any mode size.