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This paper describes molecular layer doping of Ge nanowires. Molecules containing dopant atoms are chemically bound to a germanium surface. Subsequent annealing enables the dopant atoms from the surface bound molecules to diffuse into the underlying substrate. Electrical and material characterization was carried out, including an assessment of the Ge surface, carrier concentrations and crystal quality. Significantly, the intrinsic resistance of Ge nanowires with widths down to 30 nm, doped using MLD, was found to decrease by several orders of magnitude.

A laboratory measurement of the α -decay half-life of 190 Pt has been performed using a low background Frisch grid ionisation chamber. A total amount of 216.60(17) mg of natural platinum has been measured for 75.9 days. The resulting half-life is ( 4.97 ± 0.16 ) × 10 11 years , with a total uncertainty of 3.2%. This number is in good agreement with the half-life obtained using the geological comparison method.

Display Omitted Study of a new electron beam resist, SML.Contrast is as high as PMMA.Dense grating with linewidth from ~5 to 8nm demonstrated in SML and ZEP.Etch resistance equivalent to ZEP resist. We present study on a novel, positive-tone electron beam lithography (EBL) resist known as SLM and compare its lithographic performance to well-established positive resists such as 950K polymethyl methacrylate (PMMA) and ZEP 520A. SML has been fabricated to have processing parameters similar to PMMA, but with enhanced functionality. Processing parameters such as film deposition, baking temperatures as well as the developers used for PMMA work well with SML resist.Contrast curve measurements were generated for different thicknesses of SLM and exposure voltages. Two temperature variants were employed for developing the resist with 7:3 IPA:water co-solvent developer, viz. room temperature and 0?C. To verify the resolution of SML resist, dense gratings of single pixel lines were compared to those fabricated using 950K PMMA and ZEP 520A resists. Fundamental pattern transfer skills of metal lift-off and dry etching were compared with ZEP. Metal lift-off was carried out using 5-10nm thick chromium metal and Microposit 1165 resist remover. The resilience of the SML resist to dry etching (ICP etching system with SF6 and C4F8 gas mixture) was compared to ZEP and PMMA resists and then dense gratings on ZEP and SML were etched into Si.The data obtained from the contrast curves show high contrast of the new resist. From the grating results, SML demonstrates very high resolution like ZEP and PMMA. The pattern transfer abilities of SML are also similar and in some aspects even outdo that of ZEP resist.

Supercritical resist drying allows the fabrication of high aspect-ratio (AR) resist patterns. The potential of this drying technique to increase the maximum achievable AR and the resolution of the overall lithographic process is analyzed for hydrogen silsesquioxane (HSQ). The maximum achievable AR is doubled compared to conventional nitrogen blow drying. Furthermore, the resolution is improved significantly.

Reactive ion etch (RIE) processes with HBr/O"2 chemistry are optimized for processing of functional nanostructures based on silicon and polysilicon. The etch rate, etch selectivity, anisotropy and sidewall roughness are investigated for specific applications. The potential of this process technology for nanoscale functional devices is demonstrated by MOSFETs with 12nm gate length and optimized photonic devices with ultrahigh Q-factors.

The surface roughness of hydrogen silsesquioxane (HSQ) as a negative tone electron beam (EB) resist has been studied as a function of exposure dose, developer concentration, and pre-exposure bake temperature. In the range of low exposure doses, the surface roughness of HSQ drops rapidly with an increase in the dose. It levels off at about 1 nm around the dose at which the respective contrast curve saturates. The TMAH developer concentration, varied in the range of 2.5–25%, has only a slight influence on the HSQ roughness. The increase of the baking temperature from 90 to 220 °C, however, causes a significant rise in the roughness of more than 100%. These results are discussed in terms of structural changes and network formation in thin HSQ films. They prove that a process combining high developer concentration and low baking temperature is preferable for fabrication of high resolution patterns using HSQ as a negative tone EB resist.

A dual gate metal oxide semiconductor field effect transistor (MOSFET) with electrically variable shallow junctions (EJ-MOSFET) has been fabricated on silicon on insulator (SOI) substrates. This ki ...