Photoemission Study of Interfacial Oxidation in ZrO2/subnanometer SiONx/Si(100) Stacked Structures

2002 ◽  
Vol 747 ◽  
Author(s):  
Seiichi Miyazaki ◽  
Hiroki Yamashita ◽  
Hiroshi Nakagawa ◽  
Masanori Yamaoka

ABSTRACTFor staked structures consisting of evaporated ZrO2 and ∼0.6nm-thick silicon oxynitride formed on Si(100), the blocking capability of the silicon oxynitride against oxidation in dry-O2 anneal at 500°C has been studied as a function of nitrogen content in the barrier layer in the range within ∼11at.%. With increasing nitrogen content, the interfacial oxide thickness is decreased linearly and, to suppress the growth of the interfacial oxide layer within two monolayers, a nitrogen content of ∼10at.% is necessary. Observed efficient blocking against oxidation, even for the case with a nitrogen content as small as ∼6at.%, is attributable to the improved homogeneity in the Si-O-Si bonding features at the interface by nitrogen incorporation of a few at.%, which is suggested from the experimental fact that the bandwidth of LO phonons near the interface due to the nitrogen incorporation is decreased as obtained by FT-IR-ATR measurements.

1999 ◽  
Vol 567 ◽  
Author(s):  
J. Sapjeta ◽  
M. L. Green ◽  
J. P. Chang ◽  
P. J. Silverman ◽  
T. W. Sorsch ◽  
...  

ABSTRACTThe greatest benefits of nitrogen incorporation into gate dielectrics may be obtained by placing nitrogen preferentially at the interfacial regions of the dielectric film. One method of distributing nitrogen in this manner is by using a three-step thermal process consisting of 1.) oxynitridation in NO, 2.) subsequent reoxidation in O2, and 3.) a final NO anneal. This study investigates the effect of NO processing on substrate/dielectric interface roughness and correlates that roughness with dielectric reliability. The initial NO-containing step can roughen the interface, as can subsequent reoxidation. Increased NO exposure yields a greater nitrogen content and a concomitant increase in interface roughness. These films show a degradation in charge to breakdown (Qbd) of at least an order of magnitude when compared with similarly prepared O2-oxide films. An O2/NO process produces films with interface roughness and Qbd comparable to that of pure SiO2, independent of nitrogen content. The oxynitride reliability depends on the exact scheme for incorporating nitrogen into SiO2.


2007 ◽  
Vol 1049 ◽  
Author(s):  
Yan Liu ◽  
I-Kuan Lin ◽  
Xin Zhang

AbstractSilicon oxynitride (SiON) films with different oxygen and nitrogen content were deposited by RF magnetron sputtering. Fourier-transform infrared (FT-IR) spectroscopy study revealed that co-sputterred SiON films were composed of one homogeneous phase of random bonding O-Si-N network. Time-dependent plastic deformation (creep) of SiON films were investigated by depth-sensing nanoindentation at room temperature. Results from nanoindentation creep indicated that plastic flow was relatively less homogenous with increasing nitrogen content in film composition. A deformation mechanism based on atomic bonding structure and shear transformation zone (STZ) plasticity theory was proposed to interpret creep behaviors of sputtered SiON films.


2003 ◽  
Vol 762 ◽  
Author(s):  
H. Águas ◽  
L. Pereira ◽  
A. Goullet ◽  
R. Silva ◽  
E. Fortunato ◽  
...  

AbstractIn this work we present results of a study performed on MIS diodes with the following structure: substrate (glass) / Cr (2000Å) / a-Si:H n+ (400Å) / a-Si:H i (5500Å) / oxide (0-40Å) / Au (100Å) to determine the influence of the oxide passivation layer grown by different techniques on the electrical performance of MIS devices. The results achieved show that the diodes with oxides grown using hydrogen peroxide present higher rectification factor (2×106)and signal to noise (S/N) ratio (1×107 at -1V) than the diodes with oxides obtained by the evaporation of SiO2, or by the chemical deposition of SiO2 by plasma of HMDSO (hexamethyldisiloxane), but in the case of deposited oxides, the breakdown voltage is higher, 30V instead of 3-10 V for grown oxides. The ideal oxide thickness, determined by spectroscopic ellipsometry, is dependent on the method used to grow the oxide layer and is in the range between 6 and 20 Å. The reason for this variation is related to the degree of compactation of the oxide produced, which is not relevant for applications of the diodes in the range of ± 1V, but is relevant when high breakdown voltages are required.


2007 ◽  
Vol 26-28 ◽  
pp. 937-940 ◽  
Author(s):  
Dong Jin Kim ◽  
Hyuk Chul Kwon ◽  
Seong Sik Hwang ◽  
Hong Pyo Kim

Alloy 600 is used as a material for a steam generator tubing in pressurized water reactors(PWR) due to its high corrosion resistance under a PWR environment. In spite of its corrosion resistance, a stress corrosion cracking(SCC) has occurred on the primary side as well as the secondary side of a tubing. It is known that a SCC is related to the electrochemical behaviors of an anodic dissolution and a passivation of a bare surface of metals and alloys. Therefore in the present work, the passive oxide films on Alloy 600 have been investigated as a function of the solution temperature by using a potentiodynamic polarization, electrochemical impedance spectroscopy and a TEM, equipped with EDS. Moreover the semiconductive property was evaluated by using the Mott-Schottky relation. It was found that the passivity depends on the chemical composition and the densification of the oxide film rather than the oxide thickness. As the solution temperature of 0.5M H3BO3 increased, the thickness of the passive film increased but the oxide resistance of the passive film was decreased, indicating that the measured current in the passive region of the potentiodynamic curve is closely related to the stability of the passive film rather than the oxide thickness. It was found that the oxide films were composed of an outer oxide layer with a lower resistance and an inner oxide layer with a relatively higher resistance. From the Mott-Schottky relation, the oxide formed at 300oC showed a p-type semiconductor property unlike the n-type oxide films up to 250oC.


1988 ◽  
Vol 94 (1-6) ◽  
pp. 431-434 ◽  
Author(s):  
Yoshikatsu Nagasawa ◽  
Hideyuki Ishida ◽  
Fusami Soeda ◽  
Akira Ishitani ◽  
Ichiro Yoshii ◽  
...  
Keyword(s):  
Ft Ir ◽  

2020 ◽  
Vol 1014 ◽  
pp. 144-148
Author(s):  
Ling Sang ◽  
Jing Hua Xia ◽  
Liang Tian ◽  
Fei Yang ◽  
Rui Jin ◽  
...  

The effect of the field oxidation process on the electrical characteristics of 6500V 4H-SiC JBS diodes is studied. The oxide thickness and field plate length have an effect on the reverse breakdown voltage of the SiC JBS diode. According the simulation results, we choose the optimal thickness of the oxide layer and field plate length of the SiC JBS diode. Two different field oxide deposition processes, which are plasma enhanced chemical vapor deposition (PECVD) and low pressure chemical vapor deposition (LPCVD), are compared in our paper. When the reverse voltage is 6600V, the reverse leakage current of SiC JBS diodes with the field oxide layer obtained by LPCVD process is 0.7 μA, which is 60% lower than that of PECVD process. When the forward current is 25 A, the forward voltage of SiC JBS diodes with the field oxide layer obtained by LPCVD process is 3.75 V, which is 10% higher than that of PECVD process. There should be a trade-off between the forward and reverse characteristics in the actual high power and high temperature applications.


2018 ◽  
Vol 924 ◽  
pp. 273-276 ◽  
Author(s):  
Masanobu Yoshikawa ◽  
Keiko Inoue ◽  
Junichiro Sameshima ◽  
Hirohumi Seki

We measured Fourier transform infrared (FT-IR) and cathodoluminescence (CL) spectra of SiO2 films with a various thickness, grown on 4H-SiC substrates. The peak frequency of the transverse optical (TO) phonon mode was blue-shifted by about 5 cm−1 as the oxide-layer thickness decreased from 50-60 nm to 10 nm. The blue shift of the TO mode is considerd to be caused by interfacial compressive stresses in the oxide-layer. On the other hand, the TO phonon mode was found to dramatically decrease as the oxide-layer thickness decreased from 10 nm to 1.7 nm. The CL measurement indicates that the intensity of the CL peaks at about 460 and 490 nm attributed to oxygen vacancy centers (OVCs) for No.2 become stronger than that for No.1. From a comparison between FT-IR and CL measurements, we concluded that the red-shift of the TO phonon with decreasing the oxide-layer thickness can mainly be attributed to an increase in inhomogeneity at the SiO2/SiC interface with decreasing oxide-layer thickness.


2000 ◽  
Vol 15 (2) ◽  
pp. 546-553 ◽  
Author(s):  
S. A. Syed Asif ◽  
K. J. Wahl ◽  
R. J. Colton

In this article we report the influence of surface oxides and relative humidity on the nanomechanical response of hydrophobic and hydrophilic Si surfaces. Depth-sensing nanoindentation combined with force modulation enabled measurement of surface forces, surface energy, and interaction stiffness prior to contact. Several regimes of contact were investigated: pre-contact, apparent contact, elastic contact, and elasto-plastic contact. Both humidity and surface preparation influenced the surface mechanical properties in the pre- and apparent-contact regimes. Meniscus formation was observed for both hydrophobic and hydrophilic surfaces at high humidity. Influence of humidity was much less pronounced on hydrophobic surfaces and was fully reversible. In the elastic and elasto-plastic regimes, the mechanical response was dependent on oxide layer thickness. Irreversibility at small loads (300 nN) was due to the deformation of the surface oxide. Above 1 μN, the deformation was elastic until the mean contact pressure reached 11 GPa, whereby Si underwent a pressure-induced phase transformation resulting in oxide layer pop-in and breakthrough. The critical load required for pop-in was dependent on oxide thickness and tip radius. For thicker oxide layers, substrate influence was reduced and plastic deformation occurred within the oxide film itself without pop-in. Elastic modulus and hardness of both the oxide layer and Si substrate were measured quantitatively for depths <5 nm.


2015 ◽  
Vol 180 ◽  
pp. 113-135 ◽  
Author(s):  
M. Momeni ◽  
J. C. Wren

We have developed a corrosion model that can predict metal oxide growth and dissolution rates as a function of time for a range of solution conditions. Our model considers electrochemical reactions at the metal/oxide and oxide/solution interfaces, and the metal cation flux from the metal to the solution phase through a growing oxide layer, and formulates the key processes using classical chemical reaction rate or flux equations. The model imposes mass and charge balance and hence, is labeled as the Mass Charge Balance (MCB) model. Mass and charge balance dictate that at any given time the oxidation (or metal cation) flux must be equal to the sum of the oxide growth flux and the dissolution flux. For each redox reaction leading to the formation of a specific oxide, the metal oxidation flux is formulated using a modified Butler–Volmer equation with an oxide-thickness-dependent effective overpotential. The oxide growth and dissolution fluxes have a first-order dependence on the metal cation flux. The rate constant for oxide formation also follows an Arrhenius dependence on the potential drop across the oxide layer and hence decreases exponentially with oxide thickness. This model is able to predict the time-dependent potentiostatic corrosion behaviour of both pure iron, and Co–Cr and Fe–Ni–Cr alloys.


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