Author: Jasbir S. JunejaPublisher:
ISBN:
Category :
Languages : en
Pages : 31
Book Description
Effect of Substrate Temperature on the Dielectric Properties of Ta2O5 Films Deposited by Reactive Pulsed Magnetron Sputtering
Author: Jasbir S. JunejaCeramic Abstracts
Author: American Ceramic SocietyPublisher:
ISBN:
Category : Ceramics
Languages : en
Pages : 1150
Book Description
Investigations on Magnetron Sputtered Tantalum Oxide Films
Author: S. V. Jagadeesh ChandraPublisher: LAP Lambert Academic Publishing
ISBN: 9783843394222
Category :
Languages : en
Pages : 188
Book Description
High permittivity dielectrics are studied intensively in the view of their use in the integrated circuits. However, the real emergence of tantalum oxide (Ta2O5) as a dielectric material happened due to its high-dielectric constant, chemical and thermal stability with the promise of compatibility in microelectronic processing. This book covenants with the optimized deposition conditions of Ta2O5 films formed on quartz and p-type Si substrates using dc and rf reactive magnetron sputtering method for structural and optical studies. Further, aluminum metal deposited as a top electrode on Ta2O5 and Si stack to prepare metal oxide semiconductor device for investigating electrical and dielectric properties. The possible ways for depositing good quality Ta2O5 layers on Si, to obtain high dielectric constant explained in this book are quite useful to prepare high quality metal oxide semiconductor device for capacitor applications.
Tantalum Oxide Thin Films for Microelectronic Applications
Author: Fang-Xing JiangPublisher:
ISBN:
Category : Thin films
Languages : en
Pages : 222
Book Description
"There is a critical demand for new dielectric films having higher dielectric constants, higher dielectric strengths and lower leakage currents for applications such as charge storage capacitors for DRAMs in ULSI and low-inductance decoupling capacitors for the control of simultaneous switching noise (SSN) in high-speed switching ULSI chips. Among these candidates for insulators, tantalum pentoxide has received considerable attention. As earlier as in the 1960's, tantalum oxide has been used as the dielectric in discrete capacitors. Recently, several papers have been reported on the electrical properties of Ta205 films grown by various techniques. It has been reported that the electrical properties, e.g. dielectric constant, leakage current, dielectric strength as well as the nature of the Ta2Os/Si interface, are extremely sensitive to the annealing conditions. At the present time, however, the role of the as-deposited Ta2Os/Si interface is not fully understood. In the present study, a two-step process, consisting two separate depositions and annealing, has been developed to improve the physical and electrical characteristics of reactivity sputtered Ta2Os films. The reactive ion etching (RE) selectivity of Ta2Os to Si, Si02 and Ta in CHF3, CF4 and SF6 with fractions of 02, H2 and Ar has been investigated for IC process applications. The tantalum oxide films were deposited on Si wafers by reactive DC sputtering. The films were characterized for thickness and refractive index using an ellipsometer and their phase was identified using an X-ray diffractometer. The annealing effect on Ta2Oj in oxygen ambient at 800C shows that the Ta205 films crystallize into an orthorhombic phase, condensed with a decrease of thickness and an increase of refractive index. Various capacitor configurations, such as MTM (Al/Ta205/Al) and MIS (Al/Ta20$/p-Si, Al/Ta205/n-Si and Al/Ta2Os/n+-Si), were fabricated to study the nature of Ta2Os/Si interface and the I-V and C-V characteristics. The as-deposited Ta2Os film on p-type Si substrate can sustain an electric field of 3 MV/cm at a current density of 1 u.A/cm2 in the accumulation mode, which is an order higher than that on n-type substrate. The value of apparent dielectric constant of as-deposited Ta2Os film estimated from the Al/Ta205/Al capacitor is 16, however, the value varies from 6 to 10 in MIS capacitors. This shows a evidence strongly that there is a substrate sensitivity for tantalum oxide films. As a result of the two-step process, the dielectric constant of Al/Ta2Os/n+-Si capacitor increases to 21. This value is considerably close to 24 for bulk Ta2Oj. To investigate the RIE selectivity of Ta2Os to Ta, Si and Si02, the Ta2Os film was deposited onto a wafer with three other films, DC sputtered Ta, LPCVD polysilicon, and thermally grown Si02. It is revealed that in SF6 with various fractions of 20% hydrogen or argon, the Ta2Os film shows extremely low etch rate as compared with Si, Ta and Si02, and in CF4 with various fractions of 30% hydrogen or oxygen, the Ta205 film shows a lower etch rate. However, in CHF3 the etch rates of Si and Ta2Os are comparable. The absorption spectrum of deposited tantalum oxide films was also measured. This material can be used for phase shift and attenuation masks, sunglasses and light filters. The as-deposited tantalum oxide films show a high absorbency peak at 217 nm and an additional small peak. at 416 nm with two subpeaks at 286 and 510 nm using spectrophotometer. The high peak becomes broadened and the long wavelength side of the small peak is shifted to short wavelength through annealing. A model of free volume like defect and oxygen vacancy like defect is proposed to explain the change of the absorbency spectrum."--Abstract.
Electrical & Electronics Abstracts
Author: Publisher:
ISBN:
Category : Electrical engineering
Languages : en
Pages : 1904
Book Description
Reactive Ion Enhanced Magnetron Sputtering of Nitride Thin Films
Author: Al-Ahsan TalukderPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 0
Book Description
Magnetron sputtering is a popular vacuum plasma coating technique used for depositing metals, dielectrics, semiconductors, alloys, and compounds onto a wide range of substrates. In this work, we present two popular types of magnetron sputtering, i.e., pulsed DC and RF magnetron sputtering, for depositing piezoelectric aluminum nitride (AlN) thin films with high Young's modulus. The effects of important process parameters on the plasma I-V characteristics, deposition rate, and the properties of the deposited AlN films, are studied comprehensively. The effects of these process parameters on Young's modulus of the deposited films are also presented. Scanning electron microscope imaging revealed a c-axis oriented columnar growth of AlN. Performance of surface acoustic devices, utilizing the AlN films deposited by magnetron sputtering, are also presented, which confirms the differences in qualities and microstructures of the pulsed DC and RF sputtered films. The RF sputtered AlN films showed a denser microstructure with smaller grains and a smoother surface than the pulsed DC sputtered films. However, the deposition rate of RF sputtering is about half of the pulsed DC sputtering process. We also present a novel ion source enhanced pulsed DC magnetron sputtering for depositing high-quality nitrogen-doped zinc telluride (ZnTe:N) thin films. This ion source enhanced magnetron sputtering provides an increased deposition rate, efficient N-doping, and improved electrical, structural, and optical properties than the traditional magnetron sputtering. Ion source enhanced deposition leads to ZnTe:N films with smaller lattice spacing and wider X-ray diffraction peak, which indicates denser films with smaller crystallites embedded in an amorphous matrix.
Growth and Characterization of Ito Thin Film by Magnetron Sputtering
Author: Öcal TunaPublisher: LAP Lambert Academic Publishing
ISBN: 9783838365695
Category :
Languages : en
Pages : 100
Book Description
In this study Indium Tin Oxide (ITO) thin films were grown by both DC and RF magnetron sputtering techniques. To know deposition rate of ITO, system was calibrated for both DCMS and RFMS and then ITO were grown on glass substrate with the thickness of 70 nm and 40 nm by changing substrate temperature. The effect of substrate temperature, film thickness and sputtering method on structural, electrical and optical properties were investigated. The results show that substrate temperature and film thickness substantially affects the film properties, especially crystallization and resistivity. The thin films grown at the lower than 150 oC showed amorphous structure. However, crystallization was detected with the furtherincrease of substrate temperature. Band gap of ITO was calculated to be about 3.64eV at the substrate temperature of 150 oC, and itwidened with substrate temperature increment. From electrical measurements the resistivity at room temperature was obtained 1.28x10-4 and 1.29x10-4 D-cm, for DC and RF sputtered films, respectively. We also measured temperature dependence resistivity and the Hall coefficient of the films, and we calculated carrier concentration and Hall mobility."
Integrated Passive Component Technology
Author: Richard Kevin UlrichPublisher: Wiley-IEEE Press
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 410
Book Description
Table of contents
Author: 
Author: Bahadir Tunaboylu