Mihai Scarlete

Electrical and optical characterization of SiONC dielectric thin film deposited by polymer-source chemical vapor deposition

The electro-optical properties of SiONC dielectric thin films deposited by polymer-source chemical vapor deposition using an organosilane precursor has been investigated as a function of oxygen concentration in the films. SiONC thin films were characterized using capacitance-voltage (C-V), conductance-voltage (G-V), ellipsometry, and ultraviolet visible (UV-Vis) photospectroscopy. These measurements showed that the electro-optical properties of the films are greatly influenced by the atomic concentration of oxygen. The high frequency C-V measurement revealed a nearly ideal metal-oxide-semiconductor (MOS) structure behavior at high atomic concentration of oxygen (35 at. %). A relative dielectric constant as high as 6 is obtained at 10 kHz for samples with about 5 at. % of oxygen, which corresponds to high-k dielectric material. The interface trap density extracted from G-V measurement using Hill-Coleman method is as low as 3.2×1010 (cm−2 eV−1), making these films a viable high-k dielectric alternative to S...

Chemical and Structural Characterization of SiONC Dielectric Thin Film Deposited by PSCVD

Thin films of silicon oxynitrocarbide (SiONC) have been deposited on silicon by polymer-source chemical vapor deposition (PSCVD) using poly(dimethylsilane). The chemical and structural composition of these films have been investigated using Fourier transform infrared spectroscopy, elastic recoil detection spectroscopy (ERD), and X-ray photoelectron spectroscopy (XPS). ERD depth-profile analysis revealed a homogeneous film with uniform bulk concentrations for silicon, carbon, nitrogen, and oxygen. XPS analysis showed that nitrogen, oxygen, and carbon were all uniquely bonded to silicon. The oxygen nitrogen bonds were not observed in these films. XPS analysis also revealed the presence of carbon-carbon bonds associated with graphite. It was shown that the graphitic phase is limited to the surface layer of these films, and is due to unintentional carbonization at the end of the deposition process. The relatively low bulk atomic concentration of carbon in the SiONC thin films (∼ 1%) render these films a possible alternative to SiON, and could become very attractive for the fabrication of integrated optical waveguides, and as a dielectric material in variety of microelectronic and optoelectronic devices.

Fabrication and Characterization of GaAs MOS Capacitor With CVD Grown Polymer-Based Thin Film as a Gate Dielectric

GaAs Metal-Oxide-Semiconductor (MOS) capacitor using a polymer-based thin film as a gate dielectric has been fabricated and electrically characterized. The influence of the atomic concentration of oxygen in the dielectric films on the capacitance-voltage (C-V) and current-voltage characteristics of the MOS capacitors has been thoroughly investigated. The GaAs MOS capacitor obtained at low concentration of oxygen showed an almost ideal MOS capacitor behavior. The density of the interface traps extracted from the conductance-frequency measurement was found to be as low as 9.7 x 109 eV-1 cm-2. In addition, the MOS capacitor exhibits very low leakage current (6.6 10-9 A/cm2 at -1 V) and relatively high breakdown voltage (2.05 MV/cm). These characteristics make polymer-based thin films very attractive as a passivation layer and a gate dielectric for GaAs MOSFET. The ability to tune the polymer through chemical synthesis and polymer functionalization makes CVD grown polymer-based thin films very promising for the passivation of virtually any semiconductor surface.

Chapter 16 Simulation of Chemical Concepts, Systems and Processes Using Symbolic Computation Engines: From Computer-Assisted Problem-Solving Approach to Advanced Tools for Research

Publisher Summary This chapter describes the simulation of chemical concepts, systems, and processes using symbolic computation engines (SCE). It also discusses the creation of self-extracting databases and the storage of quantified versions of chemical principles. The computational power of SCE coupled to storage facilities associated with a general computer-assisted environment can be used to create and expose the principles at the creation of physical chemistry databases. The database is structured on the Bridgman table principle of the partial derivatives of state functions. The example selected in the chapter for the storage of the data in functional form is based on the consistency of the theoretical treatment of a problem with the experimental data, when the generalizing principle is not targeted. Because of the specificity of the large database required for the solution of various problems, thermodynamics is a fertile area for SCE-embedded applications designed for the storage of data in symbolic/ numerical form adapted for SCE processing. The chapter also discusses the oscillating systems involving the transamination of poly(organo)silanes during polymer-source chemical vapordeposition (PS-CVD). PS-CVD is intended to introduce a combinatorial approach for the experimental design of ceramic thin films for semiconductor and optoelectronic devices through the synthesis of semiconductor thin layers with oscillating properties.