TiB2 films co‐sputtered from boron and TiB2 targets were used as diffusion barriers between Cu thin films and Si substrates. Material characteristics of TiB2 films and metallurgical reactions of CuTiB2/false〈normalSifalse〉 system annealed in the temperature range 400–800°C for 30 min were investigated by glancing angle X‐ray diffraction, Auger electron spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, and sheet resistance measurements. The chemical composition and resistivity of the co‐sputtered TiB films are sensitive to the bias applied on the substrate. A nanocrystalline TiB2 film with a resistivity of 300 μΩ cm was obtained when a negative bias of 200 V was applied to the substrate during sputtering. After depositing a copper overlayer, we observed that the sheet resistance of the normalCufalse(180 normalnmfalse)/TiB2false(60 normalnmfalse)/false〈normalSifalse〉 system stayed at a constant value after annealing up to 600°C for 30 min; however, the sheet resistance increased by almost five orders of magnitude after annealing at 700 and 800°C. At that point, the surface morphology was seriously deteriorated and formation of Cu3normalSi was also observed. The co‐sputtered TiB2 diffusion barrier accordingly breaks down after annealing at 700°C for 30 min. © 2000 The Electrochemical Society. All rights reserved.

Salt enrichment in the topsoil, owing to one-way migration of moisture from earthen sites to air environment, is an important inducement to weathering of sites and relics, such as efflorescence, recess, slice-peeling, which becomes the most important challenge to the preservation of unearthed sites and relics. Further, salt enrichments in the topsoil of undulating earthen sites are usually inhomogeneous such that it is difficult to precisely prevent the deterioration from happening of salt enrichment in the topsoil. A case study of salt enrichment at the K9901 funerary pit of Emperor Qin’s Mausoleum Site Museum was conducted by soil column experiment and numerical simulation. The water and salt transport in the earthen sites were simulated and analyzed by HYDRUS software. The simulation of the salt enrichment process at the earthen sites demonstrated that the enrichment of soluble salt ions mainly occurs on the surface of rammed earth and increases annually; the salt damage at the earthen sites can be effectively delayed by taking an environmental control measure. These results provide a reference for the prevention of salt damage at earthen sites and facilitate the daily management of earthen sites.

TiB2, films deposited by co-sputtering from a boron and a TiB, target are evaluated as the diffusion barrier for Cu metallization. Material characteristics of the TiB, films and metallurgical interactions of the Cu/TiB2/<Si> system annealed at 400−700°C for 30 min, in a 80%Ar+20%H2 flow, were investigated by glancing angle X-ray diffraction, Auger electron spectroscopy (AES), and scanning electron microscopy (SEM). Sheet resistance was measured for electrical characterization.The composition and resistivity of the sputtered TiB1 films varied with the bias applied on the substrate. To obtain a low film resistivity, a negative bias of 200V was applied during sputtering. The resulting TiB2 film is nanocrystalline with a resistivity of 300 μΩcm. After copper deposition, the Cu/TiB2/<Si> samples have a constant sheet resistance after annealing up to 600°C for 30min. The overall sheet resistance of the sample increases by five orders of magnitude after annealing at 700°C, and scanning electron micrographs reveal that the sample surface is severely deteriorated after annealing at 700°C.