Epitaxial reactor tray base rotating speed detection device and epitaxial reactor

The invention discloses an epitaxial reactor tray base rotating speed detection device and an epitaxial reactor, and belongs to the field of semiconductors. The epitaxial reactor comprises a reaction cavity, wherein a tray base used for bearing a substrate is arranged in the reaction cavity; and the reaction cavity has an airflow channel flowing through the tray base, and an air inlet port and an air outlet port which are respectively positioned at two ends of the airflow channel. The device comprises a positioner which is arranged on the tray base and performs circular motion along with rotation of the tray base, a signal transmitter and a signal receiver which are located at an air inlet port and an air outlet port, and a speed counter which is in communication connection with the signal receiver, wherein the signal transmitter is used for transmitting laser signals periodically blocked by the positioner, the signal receiver is used for receiving the laser signals, and the speed counter is used for acquirin