共查询到20条相似文献,搜索用时 15 毫秒
1.
Christian Fachmann Lothar Frey Tim Boescke Elke Erben 《Microelectronic Engineering》2007,84(12):2883-2887
The influence of Si concentration in hafnium silicate dielectrics on thermal stability and dielectric permittivity was analyzed. A phase diagram was developed using GIXRD and FTIR measurement. The stabilization of the “higher-k” cubic/tetragonal phase for annealing temperatures up to 1000 °C with a steady increase in capacitance was demonstrated for Hf0.94Si0.06O2 films. It was also shown that the stabilization of nano-crystalline Hf0.80Si0.20O2 films can be realized for annealing temperatures up to 900 °C. The influence of TiN electrodes on the dielectric constant and the leakage current characteristic was also investigated. A permittivity increase for annealing temperatures up to 1000 °C without degradation of leakage current was shown. 相似文献
2.
M.A. PampillónP.C. Feijoo E. San Andrés M.L. LucíaA. del Prado M. Toledano-Luque 《Microelectronic Engineering》2011,88(9):2991-2996
Thin gadolinium metallic layers were deposited by high-pressure sputtering in pure Ar atmosphere. Subsequently, in situ thermal oxidation was performed at temperatures ranging from 150 to 750 °C. At an oxidation temperature of 500 °C the films show a transition from monoclinic structure to a mixture of monoclinic and cubic. Regrowth of interfacial SiOx is observed as temperature is increased, up to 1.6 nm for 750 °C. This temperature yields the lowest interface trap density, 4 × 1010 eV−1 cm−2, but the effective permittivity of the resulting dielectric is only 7.4. The reason of this low value is found on the oxidation mechanism, which yields a surface with located bumps. These bumps increase the average thickness, thus reducing the capacitance and therefore the calculated permittivity. 相似文献
3.
High quality zinc oxide thin films have been deposited on silicon substrates by reactive e-beam evaporation in an oxygen environment. The effect of the growth temperature and air annealing on the structural, optical and electrical properties has been investigated. X-ray diffraction measurements have shown that ZnO films are highly c-axis-oriented and that the linewidth of the (002) peak is sensitive to the variation of substrate temperature. The optimum growth temperature has been observed at 300 °C. Raman spectroscopy has been found to be an efficient tool to evaluate the residual stress in the as-grown ZnO films from the position of the E2 (high) mode. On the other hand, the vanishing of the 574 cm−1. Raman feature after annealing has been explained as due to an increase of grain size and the reduction of O-vacancy and Zn interstitial. The SEM images have shown that the surfaces of the electron beam evaporated ZnO became smoother for the growth temperatures higher than 300 °C. The optical transmittance is the highest at 300 °C and has been increased after annealing in air showing an improvement of the optical quality. Finally, the maximum electrical resistivity has been found at 300 °C, which explains its relation with the crystal quality and increased from 5.8×10−2 Ω cm to reach an approximate value of 109 Ω cm after annealing at 750 °C. 相似文献
4.
HfTiO thin films were prepared by r.f. magnetron co-sputtering on Si substrate. To improve the electrical properties, HfTiO thin films were post heated by rapid thermal annealing (RTA) at 400 °C, 500 °C, 600 °C and 700 °C in nitrogen. It was found that the film is amorphous below 700 °C and at 700 °C monoclinic phase HfO2 has occurred. With the increase of the annealing temperature, the film becomes denser and the refractive index increases. By electrical measurements, we found at 500 °C annealed condition, the film has the best electrical property with the largest dielectric constant of 44.0 and the lowest leakage current of 1.81 × 10−7 A/cm2, which mainly corresponds to the improved microstructure of HfTiO thin film. Using the film annealed at 500 °C as the replacement of SiO2 dielectric layer in MOSFET, combining with TiAlN metal electrode, a 10 μm gate-length MOSFET fabricated by three-step photolithography processes. From the transfer (IDS–VG) and output (IDS–VDS) characteristics, it shows a good transistor performance with a threshold voltage (Vth) of 1.6 V, a maximum drain current (Ids) of 9 × 10−4 A, and a maximum transconductance (Gm) of 2.2 × 10−5 S. 相似文献
5.
A dielectric constant of 27 was demonstrated in the as deposited state of a 5 nm thick, seven layer nanolaminate stack comprising Al2O3, HfO2 and HfTiO. It reduces to an effective dielectric constant (keff) of ∼14 due to a ∼0.8 nm interfacial layer. This results in a quantum mechanical effective oxide thickness (EOT) of ∼1.15 nm. After annealing at 950 °C in an oxygen atmosphere keff reduces to ∼10 and EOT increases to 1.91 nm. A small leakage current density of about 8 × 10−7 and 1 × 10−4 A/cm2, respectively at electric field 2 and 5 MV/cm and a breakdown electric field of about 11.5 MV/cm was achieved after annealing at 950 °C. 相似文献
6.
C.H. FuK.S. Chang-Liao Y.A. ChangY.Y. Hsu T.H. TzengT.K. Wang D.W. HehP.Y. Gu M.J. Tsai 《Microelectronic Engineering》2011,88(7):1309-1311
Annealing effects on electrical characteristics and reliability of MOS device with HfO2 or Ti/HfO2 high-k dielectric are studied in this work. For the sample with Ti/HfO2 higher-k dielectric after a post-metallization annealing (PMA) at 600 °C, its equivalent oxide thickness value is 7.6 Å and the leakage density is about 4.5 × 10−2 A/cm2. As the PMA is above 700 °C, the electrical characteristics of MOS device would be severely degraded. 相似文献
7.
Se-Ho Kim 《Microelectronic Engineering》2010,87(1):79-10160
The crystalline and electrical properties of Li doped 0.7(Ba,Sr)TiO3-0.3MgO thick film interdigital capacitors have been investigated. Screen printing method was employed to fabricate Li doped 0.7(Ba,Sr)TiO3-0.3MgO thick films on the alumina substrates. (Ba,Sr)TiO3 materials have high dielectric permittivity (>500 @ 1 MHz) and low loss tangent (0.01 @ 1 MHz) in the epitaxial thin film form. To improve dielectric properties and reduce sintering temperature, MgO and Li were added, respectively. 10 μm thick films were screen printed on the alumina substrates and then interdigital capacitors with seven fingers of 200 μm finger gap were patterned with Ag electrode. Current-voltage characteristics were analyzed with elevated temperature range. Up to 50 °C, the thick films showed positive temperature coefficient of resistivity (dρ/dT) of 6.11 × 108 Ω cm/°C, then film showed negative temperature coefficient of resistivity (dρ/dT) of −1.74 × 108 Ω cm/°C. From the microwave measurement, the relative dielectric permittivity of Li doped 0.7(Ba,Sr)TiO3-0.3MgO thick films interdigital capacitors were between 313 at 1 GHz and 265 at 7 GHz. 相似文献
8.
Hsien-Chin Chiu Hsiang-Chun Wang Chao-Wei Lin Yi-Cheng Luo Hsuan-Ling Kao Feng-Tso Chien Ping-Kuo Weng Yan-Tang Gau Hao-Wei Chuang 《Microelectronics Reliability》2013
AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors (MIS-HEMTs) using a radio-frequency magnetron sputtered ZrZnO transparent oxide layer as a gate insulator are investigated and compared with traditional GaN HEMTs. A negligible hysteresis voltage shift in the C–V curves is seen, from 0.09 V to 0.36 V, as the thickness of ZrZnO films increases. The composition of ZrZnO at different annealing temperatures is observed using X-ray photoelectron spectroscopy (XPS). The ZrZnO thin film achieves good thermal stability after 600 °C, 700 °C and 800 °C post-deposition annealing (PDA) because of its high binding energy. Based on the interface trap density analysis, Dit has a value of 2.663 × 1012 cm−2/eV for 10-nm-thick ZrZnO-gate HEMTs and demonstrates better interlayer characteristics, which results in a better slopes for the Ids degradation (5.75 × 10−1 mA/mm K−1) for operation from 77 K to 300 K. The 10-nm-thick ZrZnO-gate device also exhibits a flat and a stable 1/f noise, as VGS–Vth, and at various operating temperatures. Therefore, ZrZnO has good potential for use as the transparent film for a gate insulator that improves the GaN-based FET threshold voltage and improves the number of surface defects at various operating temperatures. 相似文献
9.
Ch.V. Subba Reddy 《Microelectronic Engineering》2006,83(2):281-285
The thermal behavior of (PVP + PVA) polyblend film have been examined using differential scanning calorimetry and scanning electron microscopy. Capacitance and loss tangent values of polyvinyl pyrrolidone (PVP) + polyvinyl alcohol (PVA) polyblend film were measured in the frequency range 1-100 kHz and temperature range 298-423 K. Dielectric permittivity of real part (ε′) was obtained from capacitance data and dielectric permittivity of imaginary part (ε″) was obtained from real part of dielectric permittivity and loss tangent values. The decrease in dielectric permittivity was observed with increasing frequency and also observed increase in dielectric permittivity with increasing temperature. The complex dielectric constant (ε*) has been described by the electric modulus M* = (1/ε*) = M′ + iM″. The data of M* has been analysed by the stretched exponential decay of the electric field, Φ(t) = exp−(t/τ0)β. 相似文献
10.
C. Adelmann D. LinL. Nyns B. SchepersA. Delabie S. Van ElshochtM. Caymax 《Microelectronic Engineering》2011,88(7):1098-1100
TaSiOx thin films with Si/(Ta + Si) mole fractions between 0 and 0.6 have been deposited using atomic-layer deposition on Si and InGaAs at 250 °C. Interface defects on InGaAs were on the order of 1012 cm−2 eV−1, which is comparable to state-of-the-art Al2O3 deposited by atomic-layer deposition using Al(CH3)3 and H2O while the dielectric permittivity of TaSiOx is considerably higher. 相似文献
11.
Ki-Won KimSung-Dal Jung Dong-Seok KimKi-Sik Im Hee-Sung KangJung-Hee Lee Youngho BaeDae-Hyuk Kwon Sorin Cristoloveanu 《Microelectronic Engineering》2011,88(7):1225-1227
Normally-off GaN-MOSFETs with Al2O3 gate dielectric have been fabricated and characterized. The Al2O3 layer is deposited by ALD and annealed under various temperatures. The saturation drain current of 330 mA/mm and the maximum transconductance of 32 mS/mm in the saturation region are not significantly modified after annealing. The subthreshold slope and the low-field mobility value are improved from 642 to 347 mV/dec and from 50 to 55 cm2 V−1 s−1, respectively. The ID-VG curve shows hysteresis due to oxide trapped charge in the Al2O3 before annealing. The amount of hysteresis reduces with the increase of annealing temperature up to 750 °C. The Al2O3 layer starts to crystallize at a temperature of 850 °C and its insulating property deteriorates. 相似文献
12.
C. Baristiran Kaynak M. Lukosius B. Tillack Ch. Wenger S. Rushworth 《Microelectronic Engineering》2010,87(12):2561-2564
The annealing effects on dielectric and electrode materials in Ti/SrTaO/TaN/TiN/Ti/Si metal-insulator-metal (MIM) capacitors were studied. The electrical and structural properties were investigated after subjecting the samples to annealing temperatures of 500 °C, 700 °C and 900 °C. The electrical results revealed that the dielectric constant (k value) of Sr-Ta-O increased from 18 to 50 with increasing annealing temperature. This improvement in k value can be associated to the crystallization of dielectric layer. However, the leakage current density increased several orders of magnitudes with increase of the annealing temperatures. This observation was attributed to crystallization of dielectric, degradation of TaN electrode and out-diffusion of Si from the substrate. 相似文献
13.
Titanium oxide (TiO2) has been extensively applied in the medical area due to its proved biocompatibility with human cells [1]. This work presents the characterization of titanium oxide thin films as a potential dielectric to be applied in ion sensitive field-effect transistors. The films were obtained by rapid thermal oxidation and annealing (at 300, 600, 960 and 1200 °C) of thin titanium films of different thicknesses (5 nm, 10 nm and 20 nm) deposited by e-beam evaporation on silicon wafers. These films were analyzed as-deposited and after annealing in forming gas for 25 min by Ellipsometry, Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy (RAMAN), Atomic Force Microscopy (AFM), Rutherford Backscattering Spectroscopy (RBS) and Ti-K edge X-ray Absorption Near Edge Structure (XANES). Thin film thickness, roughness, surface grain sizes, refractive indexes and oxygen concentration depend on the oxidation and annealing temperature. Structural characterization showed mainly presence of the crystalline rutile phase, however, other oxides such Ti2O3, an interfacial SiO2 layer between the dielectric and the substrate and the anatase crystalline phase of TiO2 films were also identified. Electrical characteristics were obtained by means of I-V and C-V measured curves of Al/Si/TiOx/Al capacitors. These curves showed that the films had high dielectric constants between 12 and 33, interface charge density of about 1010/cm2 and leakage current density between 1 and 10−4 A/cm2. Field-effect transistors were fabricated in order to analyze ID x VDS and log ID × Bias curves. Early voltage value of −1629 V, ROUT value of 215 MΩ and slope of 100 mV/dec were determined for the 20 nm TiOx film thermally treated at 960 °C. 相似文献
14.
V. Rajagopal Reddy M. Sivapratap Reddy P. Koteswara Rao 《Microelectronic Engineering》2010,87(2):117-121
Rapid thermal annealing effects on deep level defects in the n-type GaN layer grown by metalorganic chemical vapor deposition (MOCVD) have been characterized using deep level transient spectroscopy (DLTS) technique. The samples were first characterized by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The measurements showed that the barrier height of the as-grown sample to be 0.74 eV (I-V) and 0.95 eV (C-V) respectively. However, the Schottky barrier height of the sample annealed at 800 °C increased to 0.84 eV (I-V) and 0.99 eV (C-V) respectively in nitrogen atmosphere for 1 min. Further, it was observed that the Schottky barrier height slightly decreased after annealing at 900 °C. DLTS results showed that the two deep levels are identified in as-grown sample (E1 and E3), which have activation energies of 0.19 ± 0.01 eV and 0.80 ± 0.01 eV with capture cross-sections 2.06 × 10−17 cm2 and 7.68 × 10−18 cm2, which can be related to point defects. After annealing at 700 °C, the appearance of one new peak (E2) at activation energy of 0.49 ± 0.02 eV with capture-cross section σn = 5.43 × 10−17 cm2, suggest that E2 level is most probably associated with the nitrogen antisites. Thermal annealing at 800 °C caused the E1 and E3 levels to be annealed out, which suggest that they are most probably associated with the point defects. After annealing at 900 °C the same (E1 and E3) deep levels are identified, which were identified in as-grown n-GaN layer. 相似文献
15.
Benedikt Schumacher Holger Geßwein Jürgen Haußelt Thomas Hanemann 《Microelectronic Engineering》2010,87(10):1978-1983
A commercially available nano-scaled barium titanate powder was compounded with a polyester-styrene reactive resin to create a high-k polymer-composite material. The influence of a temperature treatment on the filler was examined for treatment temperatures between 500 and 1200 °C. As a result grain and particle growth as well as lattice relaxation was induced into the powder particles. The resulting composite permittivity rises from 9.2 to 25.0 (at room temperature, 1 kHz, filler load 60 wt%/∼22 vol%) and the dielectric loss factor drops to values below 0.005 as a result of this treatment. The changes in lattice structure, powder morphology and composite viscosity were determined by XRD, SEM, BET, He-pycnometry and rheology measurements. The temperature dependency of the dielectric properties of the pure polymer and the composite were measured between −60 and 70 °C. The temperature dependency of the polymer matrix is superimposed with the temperature characteristic of the BaTiO3. 相似文献
16.
Yung-Hsien Wu Lun-Lun ChenWei-Chia Chen Chia-Chun LinMin-Lin Wu Jia-Rong Wu 《Microelectronic Engineering》2011,88(7):1361-1364
A Ge-stabilized tetragonal ZrO2 (t-ZrO2) film with permittivity (κ) of 36.2 was formed by depositing a ZrO2/Ge/ZrO2 laminate and a subsequent annealing at 600 °C, which is a more reliable approach to control the incorporated amount of Ge in ZrO2. On Si substrates, with thin SiON as an interfacial layer, the SiON/t-ZrO2 gate stack with equivalent oxide thickness (EOT) of 1.75 nm shows tiny amount of hysteresis and negligible frequency dispersion in capacitance-voltage (C-V) characteristics. By passivating leaky channels derived from grain boundaries with NH3 plasma, good leakage current of 4.8 × 10−8 A/cm2 at Vg = Vfb − 1 V is achieved and desirable reliability confirmed by positive bias temperature instability (PBTI) test is also obtained. 相似文献
17.
Hf-O-N and HfO2 thin films were evaluated as barrier layers for Hf-Ti-O metal oxide semiconductor capacitor structures. The films were processed by sequential pulsed laser deposition at 300 °C and ultra-violet ozone oxidation process at 500 °C. The as-deposited Hf-Ti-O films were polycrystalline in nature after oxidation at 500 °C and a fully crystallized (o)-HfTiO4 phase was formed upon high temperature annealing at 900 °C. The Hf-Ti-O films deposited on Hf-O-N barrier layer exhibited a higher dielectric constant than the films deposited on the HfO2 barrier layer. Leakage current densities lower than 5 × 10 A/cm2 were achieved with both barrier layers at a sub 20 Å equivalent oxide thickness. 相似文献
18.
V. Ioannou-Sougleridis S.F. GalataE. Golias T. SpeliotisA. Dimoulas D. GiubertoniS. Gennaro M. Barozzi 《Microelectronic Engineering》2011,88(3):254-261
In this work we demonstrate the fabrication and characterization of high performance junction diodes using annealing temperatures within the temperature range of 300-350 °C. The low temperature dopant activation was assisted by a 50 nm platinum layer which transforms into platinum germanide during annealing. The fabricated diodes exhibited high forward currents, in excess of 400 A/cm2 at ∼|0.7| V for both p+/n and n+/p diodes, with forward to reverse ratio IF/IR greater than 104. Best results for the n+/p junctions were obtained at the lower annealing temperature of 300 °C. These characteristics compare favorably with the results of either conventional or with Ni or Co assisted dopant activation annealing. The low-temperature annealing in combination with the high forward currents at low bias makes this method suitable for high performance/low operating power applications, utilizing thus high mobility germanium substrates. 相似文献
19.
H. Do?an 《Microelectronic Engineering》2008,85(4):655-658
We have identically prepared as many as eight Ni/n-GaAs/In Schottky barrier diodes (SBDs) using an n-type GaAs substrate with a doping density of about 7.3 × 1015 cm−3. The thermal stability of the Ni/n-GaAs/In Schottky diodes has been investigated by means of current-voltage (I-V) techniques after annealed for 1 min in N2 atmosphere from 200 to 700 °C. For Ni/n-GaAs/In SBDs, the Schottky barrier height Φb and ideality factor n values range from 0.853 ± 0.012 eV and 1.061 ± 0.007 (for as-deposited sample) to 0.785 ± 0.002 eV and 1.209 ± 0.005 (for 600 °C annealing). The ideality factor values remained about unchanged up to 400 °C annealing. The I-V characteristics of the devices deteriorated at 700 °C annealing. 相似文献
20.
We investigated the optical properties and the degradation process of the organic p-type semiconductor poly(triarylamine) (PTAA) in the mid infrared region. The dielectric function of PTAA was determined in the spectral region of 700 up to 6000 cm−1 by modeling ellipsometric measurements. Due to degradation at 65 °C, PTAA thin films developed carbonyl and hydroxyl features in the infrared spectra. Degradation under 85% RH additionally led to absorption signals of water. A degradation of the bare gold substrates was also observed. For bare gold films, morphology changed upon degradation and adsorption of hydrocarbons from the ambience took place. 相似文献