The several detached semiconductor bulk crystals (InSb, GaSb etc.) have been grown, since 1993, in our laboratory. These grown crystals showed micro and macro homogenous composition with high-quality crystallization and drastically enhanced crystal properties. These characterizations are in resemblance with the detached crystals grown in spacecraft (Microgravity) and Space Laboratory (International Space Station- ISS). Hence, it showed that the microgravity conditions have been spontaneously created by vertical directional solidification (VDS) experiments. Thus interested in knowing the reduced gravity, the science and technology behind the detached phenomenon. The as grown ingots photo showed in attachment.
Dear D. Gadkari
Your question is smart and very important, The answer by any is not similar
The big goals when people grow crystals of electronic devices, they intend to be the highest quality as possible as can because the lowest number of impurities, the lowest number of dislocations," Szofran says. Detached Bridgman growth is one way to make that occurs.
Therefore crystals formed by detached Bridgman growth, in particular, could lead to improved windows and substrates for infrared sensors, more accurate cosmic-ray detectors, and tiny solid-state lasers for next-generation flat-panel displays. And hard-to-predict spin-offs could create whole new categories of electronic products.
There are advantageous for this growth: 1. The surface of this crystal grown by the Bridgman method is visibly smoother where it was detached from the container wall. 2. The "hands off" growth of detached Bridgman crystals creates fewer defects in the crystals' internal structure with a higher quality crystal can be produced.
3. Image courtesy MSFC.
While,Szofran explains: "When crystal growth takes place in contact with the container wall ( meant in the lab.), the container pushes on the crystal, and that causes the atoms to be nudged out of alignment. Such 'defects,' as they're called, can cause the crystal not to perform as well [for certain applications]."
Summary:
The advantages for the growth in spec: An ideal crystal is a paragon of order and structure. The atoms that comprise it are arranged in a geometrical pattern that repeats over and over -- like the tiles in a tile floor, but in three dimensions. The precise ordering of atoms can lend a crystalline substance special properties of use in, e.g., electronic devices.
Best regard
May 6, 2015
Hamida Mohammed Bakr Darwish
Thank you Sir,
Your answer is encouraging our detached growth of bulk crystal using VDS. We are in this field since 1993 and have been grown 72 ternary detached bulk crystal in our laboratory of highest mobility crystal grown ever and high quality crystalline ingots. Now we are interested to determine regions analogous to the crystal grown in space.
With regards
Dr D B Gadkari