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Conventional patterning of HfO2 as a gate dielectric is a multistep complicated process that involves deposition of oxide, photolithography, and hard mask etching. In order to simplify the process of HfO2 patterning, the authors have developed photo- and electron beam-sensitive spin-coatable HfO2 resists for direct writing. They were prepared by reacting hafnium tert-butoxide with benzoylacetone in n-butanol and were found to be highly stable in air. Fourier transform infrared studies suggest that exposure to radiation results in the gradual removal of organic material from the resist and the enrichment of the resist with inorganics. This makes the exposed resist insoluble in organic solvents such as ethanol, thereby providing high-resolution negative patterns as small as ∼10nm wide. A silicon-on-insulator field effect transistor has been fabricated using sol-gel-derived HfO2 resist as a high-k gate dielectric and characterized over a range of temperatures. At room temperature a relatively high gate leaka...

By considering the variation in core size, the Lambda wavefunction, and accounting approximately for the centre-of-mass (CM) energy with mass number. The authors have analysed the Lambda binding energy of p-shell hypernuclei with charge-independent, central, spin- and state-dependent effective Lambda -nucleon potentials of gaussian form and Skyrme type within the shell-model framework. The fits to the data in the present analysis indicate that in earlier analyses (Lee et al. 1970, Gal et al. 1971, 1972) the roles of non-central and three-body forces have been over-emphasised, and so it is hard to place much reliance on the matrix elements of the Lambda -nucleon force. Alternatively one may say that the effect of the non-central and three-body forces can be simulated by the spin and state dependence of the interaction. The effective potentials so obtained are used to estimate the well depth of Lambda in nuclear matter and are found to give values in close agreement with the empirical estimates.

Phenomenological two-body central Lambda N potentials with possible state and spin dependence but without any hard or soft cores are used to analyse the existing low-energy Lambda p scattering data. The object is to see how far these free-state Lambda N potentials can account for the BLambda data of p-shell hypernuclei, Lambda 5He and Lambda binding to infinite nuclear matter when a suitable three-body Lambda NN force is added to these two-body potentials. The main aim of this work is to point out that by adding the Lambda NN force it is possible to choose effective Lambda N potentials whose two-body part is the same as the free Lambda N potential. The authors are able to find several such potentials. Out of many equivalent parameter sets accurate F/B data may place severe limitations on the l=1 part of the potentials, thus eliminating unphysical parameter sets. Therefore, a strong case is made for obtaining accurate F/B data.

The lamdba binding energy data of p‐shell hypernuclei have been analyzed within the shell model frame work using central, charge‐independent, spin‐ and state‐dependent effective Λ‐nucleon potentials of Gaussian form and Skyrme type. The c.m. energy in each case has been accounted for approximately and also due consideration has been given to the variation of core size and the Λ‐particle wavefunction. The fits to the data in the present analysis indicate that in earlier analyses the role of non‐central and three‐body forces has been somewhat over emphasized.