Chemical vapor deposition apparatus and its cleaning method

A chemical vapor deposition apparatus, comprising:

• a reaction chamber including a reaction chamber sidewall;
• a base positioned in the reaction chamber, wherein the base includes a base sidewall and there is an exhaust area between the base sidewall and the reaction chamber sidewall;
• an isolating device dividing the exhaust area into an exhaust chamber and a storage chamber which surround the base sidewall with internal and external arrangement, wherein the storage chamber is connected to a reaction area above the base;
• the isolating device including a sidewall, wherein a plurality of exhaust ports are set on the sidewall of the isolating device, and the exhaust chamber is connected to the storage chamber via the plurality of exhaust ports;
• wherein the plurality of exhaust ports are configured to allow reaction gases and by-products produced during reaction process of the reaction chamber to flow into the exhaust chamber, the exhaust chamber is configured to discharge the reaction gases and by-products to outside of the reaction chamber, and the storage chamber is configured to collect granulated or flaky depositions during the reaction process;
• and,
• wherein the reaction chamber further includes a movable liner surrounding the reaction area above the base, which moves up and down along the reaction chamber sidewall, and the movable liner includes a bottom end surface, and wherein the storage chamber is positioned below the movable liner such that during processing the movable liner is in up position allowing flaky depositions to fall into and collect in the storage chamber.