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N-Doped LaAlO3／Si（100） Films with High-k, Low-Leakage Current and Good Thermal Stability

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Chinese Physics Letters 2005年第1期22卷 182-184页

作者：相文峰吕惠宾陈正豪何萌陆旭兵刘丽峰郭海中周岳亮 InstituteofPhysics&centerforcondensedmatterphysics ChineseAcademyofSciencesPOBox603Beijing100080 InstituteofMicroelectronics PekingUniversityBeijing100871//DigitalDNALaboratoriesMotorolaInc.Beijing100871

High quality amorphous N-doped LaAlO3 (LaAlON) films have been deposited on Si (100) in nitrogen gas by laser molecular beam epitaxy. The chemical nature and physical distribution of N in LaAlON films has been performed by x-ray photoemission spectroscopy. Compared with LaAlO3, a significant improvement in the interfacial quality and leakage current density was obtained by nitrogen additive. At gate voltage +1V, the leakage current density of the LaAlON film with an equivalent oxide thickness as thin as 2nm is obtained to be 2.9×10−6A/cm2, which decreases almost two orders of magnitude from that of LaAlO3 film with the same thickness. Moreover, high-resolution transmission electron microscope analysis show that the LaAlON sample is still amorphous with a very sharp interface between the LaAlON layer and the Si substrate after annealed at 900 degrees C for 60s.

关键词：掺氮薄膜低泄漏电流热稳定性激光分子束

Reaction dynamics between the photonuclease triplet- excited vitamin-K3 and gua-nine nucleotide

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Chinese Science Bulletin 2004年第20期49卷 2144-2147页

作者： ZHANGHuijuan LIManyu WANGPeng FENGJuan WANGLi AIXicheng ZHANGXingkang ZHANGJianping StateKeyLaboratoryforStructuralChemistryofUnstableandStableSpecies.InstituteofChemistry.ChineseAcademyofSciences Beijing100080.China centerforcondensedmatterphysics InstituteofPhysics.ChineseAcademyofSciencesBeijing100080China

Nanosecond laser pulse photolysis was used to investigate the excited-state dynamics of the photonuclease vitamin-K3 (VK3). A spectral band peaked at 285 nm was newly observed and attributed to the triplet-excited state of VK3. In studying the photochemistry between the photonu-clease VK3 and guanine nucleotide (dGMP), we obtained spectroscopic evidence for the photo-initiated formation of both VK3 radical anion and dGMP radical cation, and thus proved the charge transfer reaction between the trip-let-excited VK3 and the ground-state dGMP.

关键词：反应动力学光核酸酶三重激发维生素K3 鸟嘌呤核甘电荷转移

Preparation of double-walled carbon nanotubes

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Chinese Science Bulletin 2004年第1期49卷 107-110页

作者： JIANGBin WEIJinquan CILijie WUDehai DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China InstituteofPhysics CenterforCondensedMatterPhysicsGroup412ChineseAcademyofSciencesBeijing100080China

Double-walled carbon nanotubes were prepared using the floating chemical vapor deposition with methane as carbon source and adding small amount of sulfur into the ferrocene catalyst. The optimized technological parameters are: the reaction temperature is 1200℃; the catalyst vapor temperature is 80℃; the flow rate of argon is 2000 SCCM; the flow rate of methane is 5 SCCM. The purified DWNTs under these optimized technological parameters have high purity above 90 wt%.

关键词：碳纳米管制备工艺甲烷化学蒸气沉积

The effect of Nb addition on the thermal stability and magnetic properties of Fe—based amorphous alloys with a wide supercooled liquid region

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Chinese Physics B 2002年第1期11卷 77-81页

作者：荣传兵徐民等 StateKeyLaboratoryofmagnetism InstituteofPhysics&CenterforCondensedMatterPhysicsChineseAcademyofSciencesBeijing100080China StateKeyLaboratoryofRapidlySolidifiedNonequilibrium

We have examined the effect of Nb addition on the thermal stability of the supercooled liquid before crystal-lization, the glass-forming ability and magnetic properties for the amorphous alloy series Fe73NbxAl5-xGe2P10C6B4and Fe63Co7NbxZr10-xB20. The supercooled liquid regions (△Tx=Tx-Tg) have maximum values of 66 and 79K,respectively, for Fe73Nb1Al4Ge2P10C6B4 and Fe63Co7Nb4Zr6B20 alloys. The saturation magnetization σs of theFe73NbxAl5-xGe2P10C6B4 alloy system is much higher than that of the Fe63Co7NbxZr10-xB20 alloy system, andis almost unchanged with an increasing Nb content from 0 to 3 at%But the σs of the Fe63Co7NbxZr10-xB20 alloysdecreases linearly with increasing Nb content. The coercive force Hc of the two alloy series can have a minimum value of31A/m for Fe73Nb1Al4Ge2P10C6B4 and 37A/m for Fe63Co7Nb4Zr6B20. All these values are for the ribbons annealedat 773 and 873K for 15min in vacuum.

关键词： supercooled liquid region ferromagnetism amorphous alloy

Three-dimensional micro- and nanometre composite aluminium patterns

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Chinese Physics B 2005年第7期14卷 1471-1476页

作者：赵小伟江鹏高燕王健雄宋礼刘东方刘利峰窦新元罗述东张增星向彦娟周维亚王刚 centerforcondensedmatterphysics InstituteofPhysicsChineseAcademyofSciencesBeijing100080China NationalCenterforNanoscienceandTechnology(NCNST) Beijing100080China

Three-dimensional micro- and nanometre composite aluminium patterns are constructed on Al substrate by using photolithography, reactive ion etching and anodization. A layer of patterned SiO2 mask is introduced as resist on the surface of Al foil, and during anodization the tilted nanopores and remaining Al microstructure are formed underneath the SiO2 mask. The existence of SiO2 mask leads to the deflection of electric field and effect on the transportation of ions, which results in the formation of laterally tilted nanopores, while the nanopores go down directly when being far from the boundaries of SiO2. The vertical and lateral anodization processes proceeding simultaneously construct the Al microstructure under the patterned SiO2 mask.

关键词： anodization micro-machine pattern

Magnetic properties of TbMn6Sn6—xGax（x=0.0—1.2） compounds

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Chinese Physics B 2002年第9期11卷 955-959页

作者：赵鹏张绍英等 StateKeyLaboratoryofMagnetism InstituteofPhysics&CenterforCondensedMatterPhysicsChineseAcademyofSciencesBeijing100080China StateKeyLaboratoryofMagnetism InstituteofPhysics&CenterforCondensedMatterP

Effects of Ga substitution for Sn on the structure and magnetic properties of TbMn6Sn6-xGax (x=0.0-1.2)compounds have been investigated by means of x-ray diffraction, magnetization measurement and 119Sn Mossbauerspectroscopy. The substitution of Ga for Sn results in a decrease in lattice constants and unit-cell volumes. Themagnetic ordering temperature decreases monotonically with increasing Ga content from 423 K for x=0.0 to 390 K forx=1.2. At room temperature, the easy magnetization direction changes from the c-axis to the ab-plane. This variationimplies that the substitution of Ga for Sn leads to a decrease in the c-axis anisotropy of the Tb sublattice. An increasein the non-magnetic Ga concentration results in a monotonic decrease of the spontaneous magnetizationMs at roomtemperature. Since there are three non-equivalent Sn sites, 2c (0.33, 0.67,0), 2d (0.33, 0.67,0.5) and 2e (0,0,0.34) in theTbMn6Sn6-xGax compounds, the 119Sn Mossbauer spectra of the TbMn6Sn6 and TbMn6Sn5.4Ga0.6 compounds canbe fitted by three sextets. The hyperfine fields (HFs) decrease in the order of HF(2d)＞HF(2e)＞HF(2c), which is inagreement with the magnetic structure.

关键词： TbMn6Sn6-xGax compounds magnetic properties structure

PHASE TRANSITION IN LAYERED PEROVSKITE LIKE MANGANATE Ca3Mn2O7 UNDER HIGH PRESSURE

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Beijing Synchrotron Radiation Facility 2001年第2期 180-186,页

作者： J.L.ZHU L.C.CHEN R.C.YU F.Y.LI J.LIU C.Q.JIN BeijingHighPressureResearchCenter ChineseAcademyofSciencesBeijing100080 LaboratoryforextremeConditionPhysics InstituteofPhysicsCenterforCondensedMatterPhysics

In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca3Mn2O7 under pressures up to 35 GPa have been Performed by using diamond anvil cell with synchrotron *** results show that the structure of layered perovskite-like manganate Ca3Mn2O7 is unstable under pressure due to the easy compression of NaCl-type *** structure of Ca3Mn2O7 underwent two phase transitions under pressures in the range of *** was at about 1.3GPa with the crystal structure changing from tetragonalt go *** other was at about 9.5GPa with the crystal structure changing form orthorhombic back to another tetragonal.

关键词：高压 X射线衍射 Ca3Mn2O7 钙钛矿结构锰酸盐晶体相变晶体结构

Strain Relaxation in BaTiO3／SrTiO3 Superlattices

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Beijing Synchrotron Radiation Facility 2001年第1期 137-140页

作者： S.F.Cui H.B.Lu 等 Instituteofphysics＆centerforcondensedmatterphysics ChineseAcaemyofSceiencesBeijing100080P.R.China L

Synchrotron X—Ray Study on Structures of Ni80Fe20／Cu Superlattices

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Beijing Synchrotron Radiation Facility 2001年第2期 76-78页

作者：杨涛麦振洪赖武彦吴忠华王德武 XUMing 罗光明柴春林 InstituteofPhysics＆centerforcondensedmatterphysics ChysicsChineseAcademyofsciencesBeijing100080 SynchrotronRadiationLaboratory InstituteofHighEnergyPhysicsChineseAcademyofSciencesBeijing100039

We have shown that,in contrast to the results in the literature,the Bragg peak intensity of Ni80Fe20/Cu superlattices is enhanced at the incident x-ray energy slightly higher than the absorption edge of the heavier element(Cu).The atomic density at Ni80Fe20/Cu interface was analysed by the diffraction anomalous fine structure technology with the incident angle of x-ray fixed at the first Bragg *** results demonstrate the epitaxy growth of Ni80Fe20/Cu *** annealing,the epitaxity of Ni80Fe20/Cu multilayers becomes poor but the local crystallinity in each layer is improved.

关键词： X射线分析微观结构原子分布 Ni80Fe20/Cu超晶格晶体生长