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The molecular organization in ultrathin polymer films (thicknesses less than 1000 angstroms) and thin polymer films (thicknesses between 1000 and 10,000 angstroms) may differ substantially from that of bulk polymers, which can lead to important differences in resulting thermophysical properties. Such constrained geometry films have been fabricated from amorphous poly(3-methyl-4-hydroxy styrene) (PMHS) and semicrystalline poly(di-n-hexyl silane) (PD6S) by means of spin-casting. The residual solvent content is substantially greater in ultrathin PMHS films, which suggests a higher glass transition temperature that results from a stronger hydrogen-bonded network as compared with that in thicker films. Crystallization of PD6S is substantially hindered in ultrathin films, in which a critical thickness of 150 angstroms is needed for crystalline morphology to exist and in which the rate of crystallization is initially slow but increases rapidly as the film approaches 500 angstroms in thickness., A synthetic polymer exhibits substantial interdependence among its chemical composition, processing protocol, and morphological structure and among its resulting mechanical, thermal, optical, and electrical properties. Typically, the bulk physical parameters [...]

The question of how mask dimensional errors impact yield is becoming increasingly critical to VLSI manufacturing. Both the magnitude and the spatial correlation of CD and registration errors are believed important to this issue. As part of a program to characterize these errors, we have had one identical test mask made on 6 different state-of-the-art mask pattern generators with widely different architectures. The test mask provides information on both registration and feature-size errors in both x- and y-directions, and does so over distances of several centimeters with spacing between measurements as small as 1 [[micro]meter]. More than 100 000 data points have been collected from these test plates using a LMS2000 optical metrology system, and are analyzed in the spatial frequency domain where error contributors as small as 1 nm can be identified. All systems were found to have similar characteristics in that most error contributors occur at a number of machine-specific spatial frequencies correlated to the particular architecture and printing strategy of the machine. Comparison of raster to vector machines show that vector machines tend to have more periodic error contributors, especially in the high spatial frequency range, which is consistent with the more complex writing fields used to achieve higher throughput.

Parallel plate and microstrip resonator measurements are carried out to determine the magnetic penetration depth, direct current (DC) breakdown current and radio frequency (RF) breakdown current for superconducting niobium nitride films. Results show that the films have a large magnetic penetration depth. This indicates that significant inductive nonlinearities will arise when the film are constructed with narrow transmission lines. The data also show that the transmission lines' current carrying capacity can be estimated by deriving the relationship between DC and RF critical currents.

Simple monotonic equations yield differential and total electron/atom elastic scattering cross sections for normal incidence in the range 0.1 to 0.3 kev obtained from Mott scattering cross sections based on total scattering cross section, Rutherford screening parameter and the screened to isotropic Rutherford cross section ratio. The elastic cross sections predict backscattering cross sections that exhibit monotonicity with atomic number increase and defy the periodicity of atomic models. The model represents the scattering of the electrons in a solid as a multiple scattering process.

A prototype of a 248-nm optical projection printer based on the unit magnification Dyson configuration was designed and built [J. Vac. Sci. Technol. 9, 3108 1991)]. Iterative computer methods were used to optimize the geometry of the system to provide minimum aberrations over a given field. Here we present an alternative optimization procedure and use it to design a 193-nm system. This new procedure yields useful insights into the design process and allows us to see why modifications in geometry are required for optimum performance. An understanding of the trade-offs involved in the optimization allows us to suggest and evaluate future design changes.

A novel optical spatial quantized analog-to-digital converter (ADC) is presented and the performance enhancements through employing this architecture are analyzed theoretically. A high-speed low-jitter ADC sampling clock is provided by a mode-locked laser. A high sampling rate is maintained by avoiding any speed-limiting conversion from optical to electrical domain in an all-optical quantization technique. A high quantization bandwidth is achieved by employing the all-optical quantization technique, benefiting from the high bandwidth characteristics of optical modulation. A high ADC resolution is obtained by using a single-channel quantization configuration and detecting a single image at each sampling step. A high power efficiency is achieved by extracting some portions of the required power from the analog electrical signal and optical sampling clock, directly. Various ADC-resolution limiting factors including the ambiguity of photodetector's, jitter of the optical sampling-clock, the limited beam deflector bandwidth, dispersion, phase modulator nonlinearity/mismatch, noise, and crosstalk have been identified and the contribution of each effect has been discussed. [ABSTRACT FROM PUBLISHER]

Electron beam lithography means writing patterns in thin films of electron sensitive material using a finely focused (sub-micrometre diameter) electron beam. By combining electrical scanning with interferometrically monitored mechanical motion, very complex patterns can be generated with great accuracy: for example, a pattern containing one-micrometre features can extend over 100 mm with a positional accuracy of 0.25m. In the manufacture of integrated circuits this technique is used for generating masks which are then projected optically onto silicon wafers are coated with photosensitive resists. For making circuits with sub-micrometre features the resist-coated wafer can be exposed directly with the electron beam; however this is slow because the electron beam exposure is point-by-point and there are limits to electron beam intensity and resist sensitivity. Overcoming this limit is possible using techniques which allow the exposure of many points simultaneously but such techniques are not yet widespread. Competing techniques are ion beam lithography and X-ray lithography. [ABSTRACT FROM AUTHOR]

A first-order discussion of convective heat removal from a hypothetical 3-dimensional computing system is presented. A textbook treatment indicates that our heat removal capability can be characterized by a quantity Q, the amount of power we can remove per unit cross-section. Thus the minimum length of the system is proportional to the square root of the total power dissipated. We predict Q ∼ 10[sup 4] W cm[sup −2] assuming an applied pressure difference of 1 atm, a maximum temperature rise of 100 K and the use of water as the coolant fluid. [ABSTRACT FROM AUTHOR]