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The cohesive failure which occurs in the inside of the polymer near the metal/polymer interface was studied in the Cu/Cr/polyimide and Cu/CuCr/polyimide systems. The interface energy was varied by pretreating the polyimide surface by varying rf plasma power density, or by varying the Cr content in the CuCr alloy layer, respectively, and peel tests were conducted. Then, peeled metal strips were analyzed by AES and XPS, and correlations were made among the peel strength, the amount of carbide-like Cr–C bonds near the interface, and the polyimide thickness on peeled metal films inferred from the AES depth profiling. Results indicate that the peel strength increased with the rf power density at a constant metal thickness and that the thickness of polyimide adhering to peeled metal films increased with the peel strength, which was related to the amount of carbide-like CrC bond near the interface affecting the interface energy. In the case of specimens with the same plasma treatment but various metal layer thickness, the thickness of polyimide on peeled metal films remained constant even though the peel strength increased with the metal layer thickness.

The interfacial fracture energies, Γ, of the Cu/Cr/polyimide system were deduced under varying Cu film thickness and pretreatment conditions based on two methods: X-ray measurement by Park and Yu and theoretical methods by Moidu et al. The two methods showed reasonable agreement for most cases, imparting validity for both approaches. Estimated Γ values were quite independent of the metal film thickness and increased with the rf plasma power density of polyimide pretreatment as expected. Estimated values of Γ were 46.8±17.8, 170.3±42.9 and 253.9±44.4 J m−2 for the rf plasma power density of 0.03, 0.036 and 0.05 W cm−2, respectively.

In order to understand the effects of plastic deformation and the interfacial fracture energy on the peel strength, thickness of the metal layer and the pretreatment conditions of polyimide were varied in the Cu/Cr polyimide system. The work expenditure during the peel test was estimated using the stress–strain curves of metal films, X-ray measurements of the plastic strain in peeled films, and the elastoplastic beam analysis. Results indicate that the peel strength is strongly affected by the film thickness and the pretreatment condition in a synergistic way, and that the peel strength shows a maximum at an intermediate thickness level. The estimated work expenditure was close to measured peel strength for most of the cases, which indicates that the measured peel strength is more a measure of the plastic deformation during the peel test than a measure of the true interfacial fracture energy.

A new method of frequency response analysis of an adsorber, with modulation of the adsorbate molar supply instead of traditional modulation of the reservoir volume, is presented. A semi-batch mode of operation is considered, for three different types of mass transfer mechanisms inside the particle: Langmuir kinetics, micropore diffusion and parallel pore and surface diffusion. Frequency responses to four different modes of perturbation are investigated: sinusoidal, square wave, triangular wave and saw-tooth wave. Except for the sinusoidal input modulation, the system pressure response contains higher harmonics, which makes the study of fast dynamics more feasible by using relatively low frequencies of the input perturbations and analyzing the higher harmonics in the output signal.

A new Local SONOS structure has been proposed for an embedded NVM cell in 0.13 /spl mu/m standard CMOS logic process. The localized storage silicon nitride layer of Local SONOS cell provides the essential properties for the embedded NVM such as the complete erase, low program current, and high on cell current from the low threshold voltage. The entire embedded memory solution has been realized with 0.276 /spl mu/m/sup 2/ Local SONOS NVM cell, which has 20 /spl mu/s program and 2 ms erase speed under 5.5 V bias condition, and good reliability without the special algorithms and cell array modifications.

An anodic aluminum oxide (AAO) template, which is filled with the Co–Pt alloys, is a promising material for high-density magnetic recording media due to its high magnetic anisotropy and high coercivity. The porous AAO templates were fabricated by the two-step anodizing of 1-μm-thick Al thin film evaporated on top of the titanium layer with the thickness of 250 nm. The AAO template with pore size of approximately 60 nm and aspect ratio of 10 was obtained at voltage of 40 V, temperature of 5 °C, oxalic acid of 0.3 M and widening time of 55 min. Then the thickness of barrier is less than 20 nm. The Co–Pt alloy electrodeposited at pulsed current density, pH of 4 and room temperature was successfully filled in the AAO template with pore size of 80 nm and aspect ratio of 3. Then the Co–Pt alloy with Pt concentration of 45 at% was uniformly filled in the template and the coercivity of 1100 Oe was observed by VSM.

A single layer of CuCr alloy was sputter deposited on polyimide films instead of Cu/Cr double layers. The adhesion strengths of the metal/polyimide thin films were measured by the peel test. In order to study the effects of temperature and humidity on the adhesion strength, 85 ‡C/85% R.H. (T/H) treatments were applied to the specimens. Results showed that the peel strength without T/H treatments increased proportionally with the Cr content in the CuCr alloy layer(x) up to 17 at%, and then saturated. Among the samples studied, the peel strength decreased with hold time under T/H conditions for all the cases, but most drastically for the sample with x=8.5. The very poor peel strength of that sample (x=8.5) was attributed to the occurrence of interfacial failures, which were thought to take place along CuCr oxide/polyimide interfaces.