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Multiwalled carbon nanotubes (CNTs) have been grown by remote plasma-enhanced chemical vapor deposition at temperatures as low as 400 °C. In via formation, the selective growth of CNT bundles in via holes at 430 °C and chemical mechanical polishing for planarization have been performed. The electrical evaluation of CNT single vias with various diameters reveals that the via resistance is inversely proportional to the via area. This result indicates that the CNTs are grown with uniform quality and density in the via holes with various diameters and stable contact formations are obtained. Moreover, the resistances of single vias are approximately equivalent to the via resistances estimated from the resistances of via chains, demonstrating the via-to-via uniformity of the CNT vias obtained by the remote plasma-enhanced chemical vapor deposition.

Oxygen incorporation into In0.5(Ga1-x Al x )0.5P grown by metalorganic chemical vapor deposition has been quantitatively investigated as a function of growth parameters. The oxygen concentration (N O) increased with increasing Al composition (x). Marked decreases in N O for x=0.7 and 1.0 were observed as the V/III ratio (molar flow rate ratio of group-V to group-III sources) was increased, although N O for x=0.7 was almost independent of the substrate temperature (T S). Since N O for x=1.0 was strongly affected by the amount of oxygen-containing species in trimethylaluminum (TMA), the origin of oxygen in InGaAlP is thought to be TMA. Net acceptor concentration (N A-N D) in Zn-doped InGaAlP for x=0.7 and 1.0 decreased with increasing N O. Oxygen may act as a deep donor, compensating for Zn acceptors.