Reactive sputtering method and reactive sputtering apparatus
The present invention provides a reactive sputtering method and a reactive sputtering apparatus which suppress a film quality change caused by a temperature variation in continuous substrate processing. An embodiment of the present invention performs reactive sputtering while adjusting a flow rate of reactive gas according to the temperature of a constituent member facing a sputtering space. Specifically, a temperature sensor is provided on a shield and the flow rate is adjusted according to the temperature. Thereby, even when a degassing amount of a film adhering to the shield changes, a partial pressure of reactive gas can be set to a predetermined value. For a resistance change layer constituting a ReRAM, a perovskite material such as PrCaMn03 (PCMO), LaSrMnO3 (LSMO), and GdBaCoxOy (GBCO), a two-element type transition metal oxide material which has a composition shifted from a stoichiometric one, such as nickel oxide (NiO), vanadium oxide (V2O5), and the like are used.
1. A sputtering apparatus forming a deposited film on a to-be-processed substrate by sputtering, the apparatus comprising:
a container;
an electrode that is provided in the container and to which a target can be attached;
a substrate holder that is provided in the container and can hold the to-be-processed substrate;
a gas introduction means for introducing reactive gas into the container;
a radiation thermometer that measures a temperature of a member facing a sputtering space formed between the electrode and the substrate holder;
a shield plate that is provided between the substrate holder and the electrode and has an opening through which sputtered particles from the target can pass; and
a controller controlling the gas introduction means so as to reduce a flow rate of the reactive gas supplied into the container according to a rise in the temperature of the member measured by the radiation thermometer,
wherein the shield plate is configured to switch between a first state where the electrode is exposed to the sputtering space through the opening at a same time as the radiation thermometer is shielded from the sputtering space and a second state where the radiation thermometer is exposed to the sputtering space through the opening at a same time as the electrode is shielded from the sputtering space.
2. The sputtering apparatus according to claim 1 , wherein the radiation thermometer is provided on an inner surface of the container and on an opposite side of the substrate holder with respect to the shield plate.