Film formation apparatus and method of using the same

A film formation apparatus for a semiconductor process, comprising:

• a reaction chamber configured to accommodate a target substrate, wherein an inner surface of the reaction chamber contains as a main component a material selected from the group consisting of quartz and silicon carbide;
• a heater configured to heat an interior of the reaction chamber;
• an exhaust system configured to exhaust the interior of the reaction chamber;
• a film formation gas supply circuit configured to supply a film formation gas, for forming a film on the target substrate, into the reaction chamber;
• a cleaning gas supply circuit configured to supply a cleaning gas, for removing from the inner surface a by-product film derived from the film formation gas, into the reaction chamber;
• a planarizing gas supply circuit configured to supply a planarizing gas, for chemically planarizing the inner surface, into the reaction chamber, the planarizing gas containing fluorine and hydrogen fluoride;
• and
• a control section configured to control an operation of the apparatus,
• wherein the control section executes
• removing by the cleaning gas a by-product film deposited on the inner surface of the reaction chamber, while supplying the cleaning gas into the reaction chamber, and setting the interior of the reaction chamber at a first temperature and a first pressure to activate the cleaning gas;
• and
• then, chemically planarizing the inner surface of the reaction chamber by the planarizing gas, while supplying the planarizing gas into the reaction chamber, and setting the interior of the reaction chamber at a second temperature and a second pressure to activate the planarizing gas, wherein the second temperature is within a range of from 300 to 800° C.