Abstract: Provided is a cylindrical ingot manufacturing method including: an operation of supplying a silicon raw material to an inside of a crucible and heating the crucible to melt the silicon raw material; an operation of supplying a seed crystal having one end fastened to a seed shaft to the inside of the crucible; and an operation of moving the seed crystal from a lower portion of the crucible to an upper portion thereof by the crucible rotating in one direction relative to the seed shaft and the seed shaft rotating in the other direction and moving upward. According to the present disclosure, since a ring-shaped seed crystal is grown, a cylindrical silicon ingot can be manufactured, and since a cylindrical silicon ingot having an inner diameter is formed, a wafer retaining ring can be manufactured from the ingot without a coring task.

Abstract: A method of manufacturing synthetic quartz glass through an outside vapor deposition (OVD) process with improved deposition efficiency. When a hollow cylindrical synthetic quartz glass product is manufactured through an OVD method or the like, it is environmentally friendly in view of using a smaller amount of chlorine and is economical in view of requiring no separate treatment equipment, as compared to a conventional technique using silicon chloride (SiCl4). Also, the method, in which octamethylcyclotetrasiloxane is supplied to a deposition burner while being sprayed in the form of a droplet along with a high-pressure carrier gas and vaporized by the deposition burner, can effectively address the high-temperature heating and slow decomposition involved when octamethylcyclotetrasiloxane ([(CH3)2SiO]4) is used as a source for depositing silicon dioxide particles.