Search

Not Available

In order to improve the characteristics of future integrated circuits, low dielectric constant (low-k) materials are employed. In this paper we describe in detail the characteristics of k = 2.0, SICOH films treated by capacitively coupled Ar/N2and Ar/H2plasmas, which were applied in order to modify the top surface of the film. New insights were obtained about the porous structure of the pristine and the plasma treated films: analyses indicated that the investigated plasma treatments reduced the pore size in the top ten nm of the films, while partial carbon depletion was found down to a few tens of nm inside the film. For the integration of metal barriers deposited by Atomic Layer Deposition in interconnect technologies, precursor penetration into the porous low-k dielectric should be avoided. We investigated precursor penetration in the pores during TaN Atomic Layer Deposition on the pristine and the plasma treated porous low-k films. Detailed analyses showed that the plasma induced modifications resulted in a local growth enhancement and pore sealing during the first cycles of the atomic layer deposition process.

Material screening of gate dielectrics for complementary metal oxide semiconductor applications is often complicated by the inability to deposit test samples. We examine the aqueous chemical solution deposition (CSD) technique as a simple, inexpensive, and fast technique to deposit thin metal-oxide layers. We deposited Nd2O3layers on 1.2nmSiO2. The thinnest stack (7.2nm)yielded an equivalent oxide thickness (EOT) of 3.1nmwith a gate-leakage current of 1.4×10−6A∕cm2at VFB−3V. EOT scales linearly with physical thickness, allowing a k-value extraction, approximately 14. Our results suggest that aqueous CSD is a viable method for fast gate-dielectrics screening.

Rare-earth scandate materials have been identified as candidates for gate dielectrics in metal oxide semiconductor transistors because of their high thermal stability against crystallization in combination with a high-dielectric constant. In this study, tris(1-methoxy-2-methyl-2-propoxy)dysprosium [Dy(mmp)3] and Sc(mmp)3are evaluated as metallorganic chemical vapor deposition precursors for deposition of DyxScyOzon silicon at moderate temperatures (450–600°C). These temperatures allow easy integration into a standard transistor flow. The layers are uniform with a close to bulk density and smooth top surface. Electrical characterization measurements shows a gate leakage current of 1.8×10−5A∕cm2at 4.5Vfor an equivalent oxide thickness of 2.0nm. Limited hysteresis (9mV)and frequency dispersion (3% difference in accumulation capacitance between 10 and 250kHz) was observed.