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Low temperature Carbon Nano-tubes (CNTs) growth technology is developed in this work with the insert of Al (Aluminum) between Ni (Nickel) and Ti (Titanium) as the reactant. The optimized Al thicknesses are also investigated. CNTs growth at the low temperature below 400 °C is the key factor for the back end of line compatible process integration. In this work, we grow the CNTs by thermal chemical vapor deposition process at 350 and 400 °C. The low ratio of peak ID/IG in Raman spectra and scanning electron microscope images proves the CNTs material quality. On the other hand, the high thermal conductivity (k) value of ∼50 W m − 1 K − 1 is also demonstrated. Both high material quality and k value on our low temperature grown CNTs show promising opportunities for the integration of semiconductor three dimensional packages and power-via related applications.

The alleviation effect on the Schottky barrier height (SBH) (ΦB) using ultrathin titanium dioxide and hafnium dioxide dielectrics in a single layer and a bilayer stack was demonstrated. ΦB in the Pt/n-Si contact was reduced from 0.53 to −0.058, 0.3, and −0.12 eV using 3 nm TiO2, 1 nm HfO2, and high-k/high-k bilayer insertion, respectively. A maximum of 122% reduction in ΦB was obtained using bilayer dielectric insertion, which is the highest ever reduction reported so far in a Schottky diode. This was achieved by effectively passivating the semiconductor surface states by HF cleaning followed by inserting an ultrathin film produced from the novel Atomic Layer Deposition (ALD) technique. The Gaussian distribution (GD) of barrier heights all over the interface has been investigated for both Metal–Semiconductor (M–S) and Metal–Insulator–Semiconductor (M–I–S) contacts. The nonlinear behavior in a conventional Richardson plot was observed with lower values of the Richardson constant (A*). We have reported the surface inhomogeneity in both M–S and M–I–S contacts through temperature dependency of diode characteristics. The standard deviation (σ) as evidence for the Gaussian distribution of barrier heights was determined using the ln(Is/T2) vs q/2kT plot. The results were validated by a modified Richardson plot where the values of A* obtained were found to be in close agreement with the known values. As the ALD technique is known for conformity and uniformity of thin films, the dielectric insertion has proved effective in mitigating the SBH. However, the inhomogeneity in both M–S and M–I–S points to the role of dipole formation at the interface.

In this work, we demonstrate the ultra-low contact resistivity of 6.7 × 10−9 Ω/cm2 by inserting 0.6 nm ZnO between Al and indium gallium arsenide (Si: 1.5 × 1019 cm−3). The metal-insulator-semiconductor tunneling diode with 0.6 nm ZnO exhibits nearly zero (0.03 eV) barrier height. We apply this contact structure on the source/drain of implant-free In0.53Ga0.47As quantum-well metal-oxide-semiconductor field-effect transistors. The excellent on-state performance such as saturation drain current of 3 × 10−4 A/μm and peak transconductance of 1250 μS/μm is obtained which is attributed to the ultra-low source/drain resistance of 190 Ω μm.

The SiGe quantum well (QW) tunneling diodes with different Si cap thickness are designed in this work to investigate the detailed mechanism of light emission for the metal-insulator-semiconductor (MIS) light-emitting diode (LED). At the accumulation (negative) gate bias, the electrons tunnel from the metal gate to the SiGe QW semiconductor substrate (p-type). Meanwhile, the negative gate bias also attracts holes in the interface of insulator and SiGe QW semiconductor and then the tunneling electrons can recombine with holes to emit the infrared. LEDs with different Si/SiGe/Si structure are used to investigate the light-emission mechanism and prove that the region of infrared emission is mainly from the interface of the insulator and semiconductor, not from the neutral region in the semiconductor substrate. The accurate energy band and carrier concentration in the SiGe QW structure with operated bias are also simulated and compared it with the experimental data. It shows that the concentrations of the tunn...