共查询到20条相似文献,搜索用时 13 毫秒
1.
The properties of TiN/TiSi2 bilayer formed by rapid thermal annealing (RTA) in an NH3 ambient after the titanium film is deposited on the silicon substrate is investigated. It is found that the formation of
TiN/TiSi2 bilayer depends on the RTA temperature and a competitive reaction for the TiN/TiSi2 bilayer occurs at 600°C. Both the TiN and TiSi2 layers represent titanium-rich films at 600°C anneal. The TiN layer has a stable structure at 700°C anneal while the TiSi2 layer has C49 and C54 phase. Both the TiN and TiSi2 layers have stable structures and stoichiometries at 800°C anneal. When the TiN/TiSi2 bilayer is formed, the redistribution of boron atoms within the TiSi2 layer gets active as the anneal temperature is increased. According to secondary ion mass spectroscopy analysis, boron atoms
pile up within the TiN layer and at the TiSi2−Si interface. The electrical properties for n+ and p+ contacts are investigated. The n+ contact resistance increases slightly with increasing annealing temperature but the p+ contact resistance decreases. The leakage current indicates degradation of the contact at high annealing temperature for
both n+ and p+ junctions. 相似文献
2.
P. Tiwari Mary Longo G. Matera S. Sharan P. L. Smith J. Narayan 《Journal of Electronic Materials》1991,20(7):775-778
We have investigated the formation of TiSi2 and CoSi2 thin films on Si(100) substrates using laser (wave length 248 nm, pulse duration 40 ns and repetition rate 5 Hz) physical
vapor deposition (LPVD). The films were deposited from solid targets of TiSi2 and CoSi2 in vacuum with the substrate temperature optimized at 600° C. The films were characterized using x-ray diffraction, scanning
electron microscopy (SEM), transmission electron microscopy (TEM) and four point probe ac resistivity. The films were found
to be polycrystalline with a texture. The room temperature resistivity was found to be 16 μΩ-@#@ cm and 23 μΩ-cm for TiSi2 and CoSi2 films, respectively. We optimized the processing parameters so as to get particulate free surface. TEM results show that
the silicide/silicon interface is quite smooth and there is no perceptible interdiffusion across the interface. 相似文献
3.
Selective deposition of TiSi2 on oxide patterned wafers using low pressure chemical vapor deposition
The selective deposition of titanium disilicide was investigated using a cold-wall, low pressure chemical vapor deposition
(LPCVD) technique with silane and titanium tetrachloride as the silicon and titanium sources, respectively. In-situ hydrogen
plasma effectively cleaned the silicon wafer surface for deposition of C54 TiSi2 at 760‡ C with full selectivity. A new method using a plasma only at the beginning of the deposition of the silicide further
decreased the temperature to 680‡ C without losing selectivity. The result was a fine grained film probably due to the enhanced
nucleation rate of the silicide. Cross-sectional TEM studies showed that the silicide grew into the silicon substrate, suggesting
significant silicon consumption. The silicon substrate, consequently, seems to play a major role in the silicide formation.
Silane, on the other hand, plays a minor role as a silicon source but does act as a scavenger of HC1 in the gas or on the
silicide surface. 相似文献
4.
Temperature control and wafer-to-wafer reproducibility during momentary annealing via rapid thermal annealing is critical
for TiSi2
Self-Aligned siLICIDE (SALICIDE) processing for deep submicron complementary metal oxide semiconductor. TiSi2 must undergo a transformation from the high resistivity C49 phase to the low resistivity C54 phase for applications where
it is used as a gate conductor. A process modification to achieve improved wafer-to-wafer and within wafer temperature reproducibility
is demonstrated. It has the additional benefit to the TiSi2 salicide process of enabling anneals of reduced duration, enhancing suicide transformation to the desired phase without leading
to agglomeration. 相似文献
5.
Shallown
+ andp
+ doped source/drain contacts to silicon as small as 300 × 200 nm have been fabricated using an optimized silicided (TiSi2) contact technology. Well behaved structural and electrical characteristics were found. The electrical series resistance
through two of such contacts from metal to metal through the semiconductor contacts increases rapidly for contact sizes below
the transfer length of the contact (about 0.5 μm). This resistance increase is critically dependent on the contact resistivity
and three-dimensional current flow patterns. 相似文献
6.
W. Feng W. K. Choi L. K. Bera M. Ji C. Y. Yang 《Materials Science in Semiconductor Processing》2001,4(6)
The optical properties of as-prepared and rapid thermal oxidized (RTO) heteroepitaxial Si1−x−yGexCy alloys grown on Si substrate have been characterized using spectroscopic ellipsometry. The critical points E1, E0′, E2 band gaps were determined by line shape fitting in the second derivative spectra of the pseudo-dielectric functions. For as-prepared films, the E1 gap increases with C concentration and a linear dependence on C content was observed. However, the E2 gap decreases as the C concentration increases. For the RTO samples, the amplitude of E2 transition reduces rapidly and the E1 transition shifts to a lower energy. The reduction in the amplitude of E2 transitions is due to the presence of oxide layer. A high Ge content layer and the low C content in the RTO films account for the E1 shift to lower energy and the increase of the refractive indices. 相似文献
7.
The polyoxide with nitrogen incorporation by RTN2O process can obtain smoother interface of the polyoxide/polysilicon, thus improving the characteristics of polyoxides. However, too much nitrogen does not improve, instead, degrades, the quality of the polyoxide and to induce thickness non-uniformity. It can be found that initial hole-trapping phenomenon was observed in the polyoxides grown by rapid thermal N2O oxidation process and the higher the growth temperature is, the larger the hole-trapping rate is. The larger hole-trapping is due to more excessive nitrogen release in short time at the polyoxide/polysilicon interface at high temperature oxidation, which may induce large undulations at the Si/SiO2 interface and result in localized high electric fields to obtain smaller Qbds. However, the charge-trapping properties can be improved by the N2O-annealed process at proper temperature due to proper amount of nitrogen incorporated into the polyoxide and piled up at the interface. 相似文献
8.
V. R. Todt S. Sengupta Donglu Shi P. R. Sahm P. J. McGinn R. B. Poeppel J. R. Hull 《Journal of Electronic Materials》1994,23(11):1127-1130
YBa2Cu3Ox domains for levitation applications have been produced by a seeding technology that includes Nd1+x Ba2−x Cu3Oy seeds and melt-processing technologies such as conventional melt-textured growth, melt-texturing with PtO2 and Y2BaCuO5 additions, and the new solid-liquid-melt-growth technology. Large domains (∼20 mm) with high levitation forces (F1 up to 8.2 N) have been produced. The reproducibility of the results is good, and the capability of producing a large number
of pellets in a single batch indicates good potential for the production of large amounts of this material. 相似文献
9.
Ohmic contacts with Ti/Al/Ti/Au source and drain electrodes on A1GaN/GaN high electron mobility transistors (HEMTs) were fabricated and subjected to rapid thermal annealing (RTA) in flowing N2. The wafer was divided into 5 parts and three of them were annealed for 30 s at 700, 750, and 800 ℃, respectively, the others were annealed at 750 ℃ for 25 and 40 s. Due to the RTA, a change from Schottky contact to Ohmic contact has been obtained between the electrode layer and the A1GaN/GaN heterojunction layer. We have achieved a low specific contact resistance of 7.41 × 10-6Ω cm2 and contact resistance of 0.54 Ω.mm measured by transmission line mode (TLM), and good surface morphology and edge acuity are also desirable by annealing at 750 ℃ for 30 s. The experiments also indicate that the performance of ohmic contact is first improved, then it reaches a peak, finally degrading with annealing temperature or annealing time rising. 相似文献
10.
工艺制作源漏电极为Ti/Al/Ti/Au,并在氮气气氛中对其进行快速退火,研究不同退火条件对欧姆接触的影响。具体实验过程如下:将溅射好源漏电极的外延片分为5部分,其中3片分别在700℃,750℃和800℃下快速退火30s,并相互对比得出最佳退火温度,实验结果发现750℃条件下欧姆接触最好;其余2片在750℃下分别退火25s和40s,并与前边实验750℃ 30s情况下欧姆接触比较,得出最佳退火时间为30s。我们使用传输线模式计算出电极与外延片的欧姆接触电阻率,在750℃ 30s的快速退火条件下得到最低欧姆接触电阻率为0.54 Ω mm,与其余条件下结果比较具有较好的表面形貌和边缘。从实验中我们也得到随着退火温度和退火时间的提高,欧姆接触电阻率先降低到达最低点然后开始升高的现象,为寻找GaN HEMT欧姆接触最佳条件提供了一定依据。 相似文献
11.
In2O3-Fe2O3 nanotubes are synthesized by an electrospinning method. The as-synthesized materials are characterized by scanning electron microscope and X-ray powder diffraction. The gas sensing results show that In2O3-Fe2O3 nanotubes exhibit excellent sensing properties to acetone and formaldehyde at different operating temperatures. The responses of gas sensors based on In2O3-Fe2O3 nanotubes to 100 ppm acetone and 100 ppm formaldehyde are 25 (240℃) and 15 (260℃), and the response/recovery times are 3/7 s and 4/7 s, respectively. The responses of In2O3-Fe2O3 nanotubes to 1 ppm acetone (240℃) and formaldehyde (260℃) are 3.5 and 1.8, respectively. Moreover, the gas sensor based on In2O3-Fe2O3 nanotubes also possesses an excellent selectivity to acetone and formaldehyde. 相似文献
12.
13.
14.
Chang-Ta Yang Kuei-Shu Chang-Liao Hsin-Chun Chang Tzu-Chen Wang Wen-Fa Wu 《Microelectronic Engineering》2007,84(12):2916-2920
Interaction of HfxTayN metal gate with SiO2 and HfOxNy gate dielectrics has been extensively studied. Metal-oxide-semiconductor (MOS) device formed with SiO2 gate dielectric and HfxTayN metal gate shows satisfactory thermal stability. Time-of-flight secondary ion mass spectroscopy (TOF-SIMS) analysis results show that the diffusion depths of Hf and Ta are less significant in SiO2 gate dielectric than that in HfOxNy. Compared to HfOxNy gate dielectric, SiO2 shows better electrical properties, such as leakage current, hysteresis, interface trap density and stress-induced flat-band voltage shift. With an increase in post metallization annealing (PMA) temperature, the electrical characteristics of the MOS device with SiO2 gate dielectric remain almost unchanged, indicating its superior thermal and electrical stability. 相似文献
15.
分别采用旋涂法和水热法在FTO衬底上制备Co3O4种子层和Co3O4薄膜,再在Co3O4薄膜上水热生长Fe2O3纳米棒,获得了高质量的Co3O4/Fe2O3异质结复合材料。通过改变Fe2O3前驱体溶液浓度来改变异质结复合材料中Fe2O3组分的含量。结果表明,Fe2O3纳米棒覆盖在呈网状结构的Co3O4薄膜上,随着Fe2O3前驱体溶液浓度即Fe2O3组分含量的增加,Co3O4/Fe2O3异质结复合材料对紫外光的响应逐渐增强,当Fe2O3前驱体溶液浓度为0.015mol/L时,异质结复合材料有着很好的光电稳定性,并表现出较高的响应率(12.5mA/W)和探测率(4.4×1010Jones)。 相似文献
16.
This work compares CoxMoyO, CoxFeyO and FexMoyO alloying metal oxide nanoparticles (AMONs) that were individually embedded in HfOxNy high-k dielectric as charge trapping nodes. They were formed by chemical vapor deposition using Co/Mo, Co/Fe and Fe/Mo acetate, respectively, calcined and reduced in Ar/NH3 ambient. The effects of various pre-treatments on CoxMoyO, CoxFeyO and FexMoyO AMONs preparation were investigated. The results indicate that the larger charge trap density, larger memory window and better programming characteristics of CoxMoyO AMONs are attributable to their higher surface density and smaller diameter. The average collected charge in each CoxMoyO AMON is the smallest among three AMONs, revealing that a local leakage path is associated with the least charge loss. The main mechanism that governs the programming characteristics involves the trapping of holes. 相似文献
17.
18.
Ho Jin Cho Young Dae Kim Dong Su Park Euna Lee Cheol Hwan Park Jun Soo Jang Keum Bum Lee Hai Won Kim Young Jong Ki Il Keun Han Yong Wook Song 《Solid-state electronics》2007,51(11-12):1529
New ZrO2/Al2O3/ZrO2 (ZAZ) dielectric film was successfully developed for DRAM capacitor dielectrics of 60 nm and below technologies. ZAZ dielectric film grown by ALD has a mixture structure of crystalline phase ZrO2 and amorphous phase Al2O3 in order to optimize dielectric properties. ZAZ TIT capacitor showed small Tox.eq of 8.5 Å and a low leakage current density of 0.35 fA/cell, which meet leakage current criteria of 0.5 fA/cell for mass production. ZAZ TIT capacitor showed a smaller cap leak fail bit than HAH capacitor and stable leakage current up to 550 °C anneal. TDDB (time dependent dielectric breakdown) behavior reliably satisfied the 10-year lifetime criteria within operation voltage range. 相似文献
19.
P. Lange H. Neff M. L. Fearheiley K. J. Bachmann 《Journal of Electronic Materials》1985,14(6):667-676
Photoluminescence spectra are presented for single crystals of CuInS2, CuInSe2 and CuInS2ySe2-2y alloys. The PL spectrum of stoichiometric CuInSe2 is dominated by free exciton emission of 9 meV FWHM at 1.03 eV, but structure at 090, 0.94 and 0.97 eV is observed due to
transitions involving residual native defect states. For pure CuInS2 broad deep luminescence bands are obtained that involve several deep native defect states, e.g. donors at 45 and 160 meV
below the CBE and acceptors at 85 meV above the VBE. These defects persist in S-rich CuInS2/CuInSe2 alloys, but excitonic emission is observed, in addition to the deep luminescence. Surprisingly CuInS2ySe2-2y crystals at y ≳ l are totally dominated by free exciton emission. This result shows that an increase of at least 20% over
the bandgap of CuInSe2 and excellent crystal quality can be achieved by partial substitution of Se by S. 相似文献
20.
The growth parameters and some physical properties of lanthanum-modified strontium barium niobate crystals, grown by the Czochralski
method, have been investigated. Crystals were grown from melts having lanthana, La2O3 concentrations ranging from 0.01 to 1.50% (by weight;, the Sr to Ba ratio was one. Knoop microhardness was measured as a
function of La content and the hardness was found to decrease with increasing La content. Room temperature compressive strength
measurements were also made. None of the samples tested exhibited yielding. Fracture stresses did not change in a sensible
manner as a function of La content. Lattice parameter measurements were made using x-ray diffraction and showed that the ‘c’
parameter decreased while the ‘a’ parameter increased slightly with increasing La content. 相似文献