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3.3.1. The kinetic coefficients at growth of crystals paratellurita

The most rough expedient of an estimate of the kinetic coefficients at growth of crystals on Chohralsky is the estimate on medial to true veptikalnoj skoposti a post:

The following expedient of an estimate - calculation of lapse rates of temperature at the front the crystallisations, spotted by regional requirements on a demarcation of phases.

In operation [54] calculation of a thermal problem for paratellurita taking into account influence of a transparency of crystals was carried out. The regional requirement for one-dimensional problem Stefana registered in a view:

Where Gsи Gl - temperature lapse rates in firm and liquid phases, L - a specific heat capacity of fusion, ps - crystal density, V - growth rate, bl - a degree of blackness of a melt, σ - stationary value Stefana-Boltsmana, TEf - effective exterior temperature which in calculations varied within 1008-500 To.

Proceeding from measurings of temperature fields in space surrounding a crystal, estimates of effective temperature in the present operation have been yielded. At an axial temperature lapse rate in a liquid phase equal 1 К-см-1, growth rates 310^5sm-s-1 and temperature on the upper screen,

Ill

30 sm being apart from level of the melt, equal 980 To, an axial temperature lapse rate in a firm phase appear equal 5 К-см-1. Comparing the given lapse rate with values of supercooling on the interphasic boundary, found by means of numeral cabinets, we find for quantity βτ medial value of the order 10^5sm/s-K.

The third expedient of an estimate - calculation according to the formula (3.18) output in the present operation, gives value for βτ ~ 10^6sm/s-K.

The fourth expedient is grounded on examination of a microrelief of a lateral surface of crystals paratellurita and presented in chapter 4 of the present operation.

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A source: Aydinyan Narek Vaagovich. the KINETICS of GROWTH of LARGE-SIZED MONOCRYSTALS paratellurita And Germany In the METHOD of the CHOHRALSKY. The dissertation on competition of a scientific degree of the candidate of physical and mathematical sciences. Tver - 2017. 2017

More on topic 3.3.1. The kinetic coefficients at growth of crystals paratellurita:

  1. 3.3.2. The kinetic coefficients at growth of crystals of germanium
  2. the kinetic coefficients of growth of facets and their anisotropy
  3. CHAPTER 3. THE OBSERVATIONAL DEFINITION OF THE KINETIC PERFORMANCES OF GROWTH FROM THE MELT OF CRYSTALS paratelurita AND GERMANY
  4. 3.3. Calculations of the kinetic coefficients
  5. 4.1. Morphology of crystals paratellurita and its communication with a crystallisation kinetics
  6. 4.3. Flaws of structure of crystals paratellurita and communication of their formation with rostovoj a kinetics
  7. Flaws of structure and optical anomalies in crystals paratellurita and germanium
  8. optical properties of the uniaxial crystals paratellurita, iiobata lithium and SBN, as objects for examinations by a conoscopy method
  9. Chapter 4. MICROMORPHOLOGY of the SURFACE of CRYSTALS paratellurita
  10. 4.5. Photolithographic microstructurization of a surface of crystals paratellurita
  11. cultivation of crystals paratellurita an expedient Chohralsky
  12. 1.5. The basic performances and scopes of optical crystals of germanium and paratellurita
  13. 2.2. Theoretical estimates of asymmetry of growth rates and fusion of crystals
  14. CHAPTER 4. INFLUENCE OF THE KINETICS ON MORPHOLOGY AND FORMATION OF FLAWS STUKTURY OF CRYSTALS paratellurita AND GERMANY
  15. CHAPTER 1. MECHANISMS OF GROWTH OF CRYSTALS FROM THE MELT (THE LITERATURE REVIEW)
  16. Normal and level-by-level growth of crystals
  17. Ajdinjan Has named Vaagovich. the KINETICS of GROWTH of LARGE-SIZED MONOCRYSTALS paratellurita And Germany In the METHOD of the CHOHRALSKY. The dissertation on competition of a scientific degree of the candidate of physical and mathematical sciences. Tver - 2017, 2017