Reactive sputtering method and reactive sputtering apparatus

Abstract

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 PrCaMnO3 (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 reactive sputtering method of sputtering a target disposed in a chamber, supplying reactive gas into the chamber, and forming a deposited film on a to-be-processed substrate disposed in the chamber by reactive sputtering, the method comprising the steps of:
 measuring a temperature of a constituent member that is provided in the chamber and faces a processing space; and   adjusting a flow rate of the reactive gas according to a rise of the measured temperature so as to reduce the flow rate of the reactive gas supplied into the chamber.   
     
     
         2 . The reactive sputtering method according to  claim 1 , wherein the flow rate of the reactive gas supplied into the chamber is adjusted according to the measured temperature so that a partial pressure of the reactive gas in the chamber falls within a predetermined range. 
     
     
         3 . The reactive sputtering method according to  claim 1 , wherein the flow rate of the reactive gas is adjusted so that a specific resistance value of the deposited film becomes a predetermined specific resistance value, using a map that preliminarily defines a relationship of the specific resistance value of the deposited film against the flow rate of the reactive gas at each temperature and a measured value of the measured temperature. 
     
     
         4 . The reactive sputtering method according to  claim 1 , wherein
 the processing space is surrounded by the target, the to-be-processed substrate, and a shield,   a temperature sensor capable of measuring a temperature of the shield is attached on the side of the to-be-processed substrate of the shield, and   the temperature of the constituent member is measured by the temperature sensor.   
     
     
         5 . The reactive sputtering method according to  claim 3 , wherein the temperature sensor is a thermocouple or a radiation thermometer. 
     
     
         6 . The reactive sputtering method according to  claim 1 , wherein the deposited film is an insulating film including an oxygen defect. 
     
     
         7 . The reactive sputtering method according to  claim 6 , wherein an element contained in the insulating film includes at least one of Ta, Ni, V, Zn, Nb, Ti, Co, W, Hf, and Al. 
     
     
         8 . The reactive sputtering method according to  claim 6 , wherein the insulating film has a laminated structure in which it is sandwiched by metals containing at least one of Ni, W, Pt, Ti, Al, Ru, Ta, and Cu. 
     
     
         9 - 11 . (canceled)