I. Silier

Thermal conductivity of isotopically enriched Si

We have used an optical pump-and-probe technique to measure the temperature dependence of the thermal conductivity, κ(T), of isotopically pure Si. The sample was made from 99.7% 28Si by liquid phase epitaxy. Measurements were performed over the temperature range of 100–375 K. We found an increase in the thermal conductivity of isotopically pure Si, as compared to Si of natural isotopic abundance, throughout the entire temperature range. The results were theoretically reproduced by appropriately scaling the parameters used recently to fit the thermal conductivity of Ge samples with different isotopic compositions. A maximum in κ(T) of ∼4×104 W m−1 K−1 is predicted for 28Si at T≃33 K.

Adhesion in growth of defect‐free silicon over silicon oxide

By applying liquid phase epitaxy, we have grown defect‐free silicon and silicon–germanium layers on partially oxide‐masked Si wafers. The growth of the layers started epitaxially in oxide‐free seeding areas and proceeded laterally over the thermal oxide film. Detailed studies by x‐ray topography and electron microscopy show that the obtained thin semiconductor‐on‐insulator layers bend towards the oxide during lateral growth. The bending of the layers can be ascribed to adhesion and interfacial forces. Adhesion operates across a gap between the closely spaced surfaces of the oxide and the epitaxial Si and facilitates lateral growth of high‐quality semiconductor layers on dissimilar layers or substrates. The technical potential of adhesion‐dependent solution growth on dissimilar substrates is discussed.

The coalescence of silicon layers grown over SiO2 by liquid-phase epitaxy

AbstractWe have investigated by liquid-phase epitaxy (LPE) the coalescence of defect-free silicon-on-insulator (SOI) layers. The SOI lamellae grow out laterally from neighbouring seeding windows and spread over the SiO2. In our study, the seeding window edges are straight. The long window edges are parallel and extend in the (111) substrate plane in

MOS transistors with epitaxial Si, laterally grown over SiO2 by liquid phase epitaxy

[11\bar 2]

Solution growth of epitaxial semiconductor-on-insulator layers

direction. Coalescence of SOI lamellae takes place without the formation of defects whenever it begins at one point and then proceeds in directions parallel to the longer edges of the windows in a “zip”-like mechanism. Defect-free coalescence seams reach lengths of up to 150 μm.

Growth of multi-crystalline silicon on seeded glass from metallic solutions

In a novel centrifuge, we perform silicon liquid‐phase epitaxy (LPE) on 100 mm diameter Si wafers. The epitaxial Si layers grow from indium solutions. The thickness uniformity of the layers is better than ±4.9% within the central circular area of 90 mm in diameter. The layers show smooth surfaces. The bulk of the layers is free of extended defects and of solution inclusions. Hall effect measurements and transmission electron microscopic observations confirm the high quality of this epitaxial material.

SiGe layer structures for solar cell application grown by liquid phase epitaxy

We describe the first MOS transistors fabricated in silicon-on-insulator layers, obtained by liquid phase epitaxial lateral overgrowth of Si over SiO2. Growth is performed around 930°–920° C using indium as a solvent. The layers are therefore p-type and have a doping of 4·1016 cm−3. Electron mobilities of 540 cm2/Vs are obtained in the inversion channel; the threshold voltage of transistors with a gate length of 14.1 μm is 510 mV. Our data demonstrate the applicability of liquid-phase epitaxial Si grown over oxidized Si for future use in three-dimensional integrated-device processing.

High-quality polycrystalline silicon layers grown on dissimilar substrates from metallic solution

This paper describes liquid phase epitaxy techniques which have been developed for growing semiconductor layers on 100 mm diameter substrates for solar cells. We have prepared Si and GaAs layered structures, whose surface textures have the shapes of pyramids, roofs, or mesa facets of different size and periodicity. Microscopic growth mechanisms influence surface and interface morphologies of the layers as well as their electronic and optical properties. Sharp doping profiles are measured at interfaces of grown layers.