Silicon oxide

About: Silicon oxide is a research topic. Over the lifetime, 22220 publications have been published within this topic receiving 260986 citations.

Alkyl monolayer passivated metal-semiconductor diodes: 2: Comparison with native silicon oxide.

Abstract: To understand the electrical properties at passivated metal–semiconductor interfaces, two types of mercury–insulator–silicon (n-type) junctions, Hg|C10H21Si and Hg|SiO2Si, were fabricated and their current–voltage and capacitance–voltage characteristics compared. Both of them exhibited near-ideal rectifying characteristics with an excellent saturation current at reverse bias, which is in contrast to the previously reported ohmic behavior of an unmodified mercury–silicon junction. The experimental results also indicated that the n-decyl monolayer passivated junction possesses a higher effective barrier height, a lower ideality factor (that is, closer to unity), and better reproducibility than that of native silicon oxide. In addition, the dopant density and build-in potential, extracted from capacitance–voltage measurements of these passivated mercury–silicon junctions, revealed that alkyl monolayer derivatization does not alter the intrinsic properties of the silicon substrate. The calculated surface state density at the alkyl monolayer|silicon interface is lower than that of the silicon oxide|silicon interface. The present study increases the possibility of using advanced organic materials as ultrathin insulator layers for miniaturized, silicon-based microelectronic devices.

Process for forming integrated circuit structure with metal silicide contacts using notched sidewall spacer on gate electrode

Abstract: A process for forming improved metal silicide contacts over the gate electrode and source/drain regions of MOS devices of an integrated circuit structure formed in a silicon substrate is described. The metal silicide contacts are formed by first forming a silicon oxide layer over exposed portions of the silicon substrate and over exposed surfaces of previously formed polysilicon gate electrodes. Silicon nitride sidewall spacers are then formed over the oxide on the sidewalls of the gate electrode by depositing a silicon nitride layer over the entire structure and then anisotropically etching the silicon nitride layer. Source/drain regions are then formed in the silicon substrate adjacent the nitride spacers and the structure is then contacted with an oxide etch to remove oxide from the upper surface of the gate electrode and the substrate surface over the source/drain regions. During the oxide etch step, notches, each having an aspect ratio of 1 or less, are formed in the exposed edges of the oxide respectively between the silicon nitride spacers and either the substrate or the gate electrode. A metal layer capable of reacting with the exposed silicon to form metal silicide contacts is then blanket deposited over the structure and into the notches. After reacting the metal with silicon surfaces with which it is in contact to form metal silicide, the unreacted metal is removed, leaving a metal silicide gate contact on the upper surface of the polysilicon gate electrode, as well as those upper portions of the sidewall of the gate electrode exposed by forming the notch in the oxide layer on the sidewall of the electrode. Metal silicide source/drain contacts of enlarged area are also formed over the exposed silicon surfaces of the source/drain regions and those portions of the silicon substrate beneath the nitride spacers exposed by the notches formed in the oxide beneath the nitride spacers.

Polyethersulfone–[silicon oxide] hybrid materials via in situ sol–gel reactions for tetra-alkoxysilanes

Abstract: Polyethersulfone (PES)–[silicon oxide] hybrids were derived via sol–gel reactions for tetraethoxysilane (TEOS) and tetramethoxysilane (TMOS) in dimethylacetamide solutions of the polymer. In one scheme, water was initially present, and condensation reactions between SiOR groups competed with their reactions with —OH groups at PES chain ends. In a second scheme, water addition was delayed; TMOS molecules reacted with chain ends before competing TMOS–TMOS reactions occurred. A third study involved parallel experiments, as follows: 1) introduction of EtOH to PES–TEOS solutions for a time before water addition; and 2) reactions occurring for a time in non-EtOH-containing PES–TEOS solutions before water addition. Infrared (IR) spectroscopy uncovered signatures of Si–O–Si bridges in silicon oxide phases and PES endgroup modifications (Si–O–Ph). Composites prepared according to the latter two schemes contain more Si–O–Ph linkages than those generated via the first. Differential scanning calorimetry showed that Tg can be raised, and thermogravimetric analysis revealed how the PES thermal degradation profile can be modified via these inorganic incorporations. The schemes for late water addition produced composites having increased elongation-to-break and lowered strength relative to unfilled PES. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1799–1810, 1998

Origin of complex impact craters on native oxide coated silicon surfaces

Abstract: Crater structures induced by impact of keV-energy ${\mathrm{Ar}}_{n}^{+}$ cluster ions on silicon surfaces are measured with atomic force microscopy. Complex crater structures consisting of a central hillock and outer rim are observed more often on targets covered with a native silicon oxide layer than on targets without the oxide layer. To explain the formation of these complex crater structures, classical molecular dynamics simulations of Ar cluster impacts on oxide coated silicon surfaces, as well as on bulk amorphous silica, amorphous Si, and crystalline Si substrates, are carried out. The diameter of the simulated hillock structures in the silicon oxide layer is in agreement with the experimental results, but the simulations cannot directly explain the height of hillocks and the outer rim structures when the oxide coated silicon substrate is free of defects. However, in simulations of $5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$/atom ${\mathrm{Ar}}_{12}$ cluster impacts, transient displacements of the amorphous silicon or silicon oxide substrate surfaces are induced in an approximately $50\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ wide area surrounding the impact point. In silicon oxide, the transient displacements induce small topographical changes on the surface in the vicinity of the central hillock. The comparison of cluster stopping mechanisms in the various silicon oxide and silicon structures shows that the largest lateral momentum is induced in the silicon oxide layer during the impact; thus, the transient displacements on the surface are stronger than in the other substrates. This can be a reason for the higher frequency of occurrence of the complex craters on oxide coated silicon.