Abstract Dy 3+ -doped YCa 4 O(BO 3 ) (Dy:YCOB) crystal was successfully grown by the Czochralski technique. The absorption cross section at 453 nm 0.28 × 10 –21 cm 2 , that is related to 6 H 15/2 ? I transition. Judd-Ofelt parameters ? t (t = 2, 4, 6) were 1.62 –20 0.10 0.41 respectively. emission assigned transition F 9/2 13/2 1.02 . energy level’s fluorescence lifetime 900 ? s.

Lithium molybdate single crystals up to one kilogram have been grown by a conventional Czochralski process. The growth configuration (geometry, coil, crucible, insulation casing) was optimized numerical simulation of heat and mass transfer. Dislocations are shown belong the basal glide system. Their density (≤104 cm−2) luminescence properties indicate crystal quality similar that previously rep...

The nature, properties and relative concentrations of electronic defects were investigated by Thermoluminescence (TL) in Lu2(1-x)Y2xSiO₅ (LYSO) single crystals. Ce and Tb-doped single crystals, grown by the Czochralski technique (CZ), revealed similar traps in TL. LYSO:Ce single crystals were grown by the Floating-Zone technique (FZ) with increasing oxygen concentration in the growth atmosphere...

For a Czochralski growth of Ge crystal, thermal fields have been analysed numerically using the three-dimensional finite volume method (FLUENT package). The arrangement used in a real Czochralski crystal growth lab included a graphite crucible, heat shield, heating device, thermal insulation and chamber including two gas outlets. We have considered two cases for calculations, which are configur...

The Czochralski process is the only method used commercially for production of monocrystalline silicon for semiconductor and solar cell applications. This paper explores the use of mathematical modeling as an aid in estimation of system state variables in the standard Czochralski process. A state-space model of the process is presented, describing the dynamics of the crystal radius and meniscus...

We have made a quantitative study about the thermal activation of thermal donors in high resistivity magnetic Czochralski silicon. The thermal donor activation has been performed through a thermal treatment at 430 1C up to a total time of 80min. The space charge density after each annealing step has been extracted from capacitance–voltage measurements. If the starting material is boron-doped p-...

A computational approach to the study of three-dimensional instabilities of flows in a Czochralski crucible is proposed. The flow is driven by buoyancy, thermocapillarity and rotation of the crystal and the crucible. The thermal boundary conditions account for the prescribed temperatures or heat flux, as well as convective and radiative heating or cooling of the boundaries. The numerical approa...

Langatate (LGT) crystals of La3Ga5.5Ta0·5O14 composition diameter 50 mm were grown from the melt by Czochralski technique. Using (1–2 wt %) Ga2O3 excess in starting charge and growing crystal mixture argon (0.1–1%O2) gas atmosphere are a good condition to crystallize LGT under stationary stable regime. The along Z-axis exhibit strong faceting. exempt inclusions, cracks secondary phases. presenc...