Automatic diameter control system applied to the laser heated pedestal growth technique

• Main Authors: Andreeta M.R.B., Caraschi L.C., Hernandes A.C.
• Format: Article
• Language: English
• Published: Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol) 2003-01-01
• Series: Materials Research
• Subjects: LHPG; single crystal fiber; diameter control; crystal growth
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392003000100019

We described an automatic diameter control system (ADC), for the laser heated pedestal growth technique, that reduces the diameter fluctuations in oxide fibers grown from unreacted and non-sinterized pedestals, to less than 2% of the average fiber diameter, and diminishes the average diameter fluctuation, over the entire length of the fiber, to less than 1%. The ADC apparatus is based on an artificial vision system that controls the pulling speed and the height of the molten zone within a precision of 30 mum. We also show that this system can be used for periodic in situ axial doping the fiber. Pure and Cr3+ doped LaAlO3 and pure LiNbO3 were usedas model materials.