Automated Multifunction system for single crystal growth by Czochralski method (Nika-3) produced by EZAN



The multifunctional system NIKA-3 is intended for growth of a wide range of refractory oxide single crystals by the Czochralski method, such as sapphire, yttrium aluminum garnet, lithium tantalate, lithium niobate, gadolinium molybdate, langasite, vanadates of rare-earth metals, bismuth silicate, bismuth germinate and many other.

NIKA-3 was developed with account of the operating experience of previous generation equipment, recommendations of our customers, natural progress of technical characteristics of the component parts and software.

  • The direct drive of pulling head actuator screw with application of step motors of NANOSTEP technology with resolution of 500,000 steps per revolution providing absence of micro-accelerations at low pulling speeds;

  • Application of long-stroke (550 mm) disc bellows for rod packing;

  • New mechanics of crystal weighing system, significantly decreasing the measurement noise at crystal rotation;

  • Software for through automation of the process;

  • Equipment is complected with transistor generator (IGBT) with output of 40 or 100 kW.

    Technical characteristics of the system:


  • Melting temperature
  • up to 2200О С
  • Crucible diameter 
  • up to 150 mm (depending on the growing crystal type)

  • Mass of growing crystal
  • up to 5 kg; 10 kg
  • Range of weight sensor measurement
  • up to 5 kg; 10 kg
  • Sensitivity of weight sensor
  • min. 0.02 g; 0.04 g
  • Operational stroke of upper rod
  • 550 mm
  • Rate of upper rod movement:
    from 0.1 to 120.0 mm/h
    from 0.5 to 150.0 mm/min
  • Rate of upper rod rotation
  • 1-100 rpm
  • Operational stroke of lower rod
  • 200 mm
  • Type of converter
  • transistor (IGBT technology)
  • Output power of converter
  • 40 kW; 100 kW
  • Range of frequency converter output power application
  • from 1 to 100 % of the applied one
  • Efficiency
  • min. 93%
  • Permissible deviation of frequency converter output power from the specified value
  • ± 0,05%
  • Inert gas pressure in chamber
  • max. 1,5x105Pa
  • Limit primary vacuum in the growing vessel with the inducer switched off
  • max. 2.6 Pa
  • Consumed power of the installation (without frequency converter)
  • max. 3 kW
  • Cooling water pressure
  • from 200 kPa to 250 kPa



    Automatic control system

    The adaptive (self-adjusting) system of automatic control over the crystal diameter provides for the necessary amount of control and stability throughout the whole growth process. The significant advantage of the ACS is availability of several classes of automatic regulators, such as self-adjusting PID-regulator, incremental regulator, self-adjusting predictor-corrector which, as the practice has shown, provides for the best quality of crystal size (ingot diameter) control. We take into consideration the features of the customer’s process and carry out automation of special processing methods and procedures.


    We take into consideration the features of the customer’s process and carry out automation of special processing methods and procedures.

     EZAN develops and implements the top-level automation systems intended for single crystal growth shop production management. The system performs the automatic collection and processing of the technological parameters, the single crystal quality analysis results, performs automatic correlation, determines the combination of optimal technological parameters for the current process, downloads them to the system control computer.