Integrated and Discrete Capacitors Based on Carbon Nanostructures with Capacitance Densities in Excess of 350 nF/​mm2

Com­plete on-chip fully sol­id-state 3D integ­rated capa­cit­ors using ver­tic­ally aligned car­bon nan­ofibers as elec­trodes to provide a large 3D sur­face in a MIM con­fig­ur­a­tion have been man­u­fac­tured and char­ac­ter­ized. The capa­cit­ance per device foot­print area has been stud­ied, as well as its beha­vi­or at dif­fer­ent tem­per­at­ures and fre­quen­cies. Equi­val­ent series res­ist­ance (ESR), break­down voltage and leak­age cur­rent have also been meas­ured. The entire man­u­fac­tur­ing pro­cess of the capa­cit­ors is com­pletely CMOS com­pat­ible, and in com­bin­a­tion with the low device pro­file of about 4 µm this makes the devices read­ily avail­able for integ­ra­tion on a CMOS-chip, in 3D stack­ing, or redis­tri­bu­tion lay­ers in a 2.5D inter­poser tech­no­logy. Capa­cit­ances of ca 350 nF/​mm², ESR of about 100 mΩ, break­down voltages of up to 25 V and leak­age cur­rents in the order of 0.004 nA/​nF have been measured.