Method of manufacturing magnetoresistive element and manufacturing system for the same

Abstract

Provided are a method of manufacturing a magnetoresistive element and a manufacturing system which are capable of manufacturing a magnetoresistive element achieving further downscaling, i.e., further increase in the degree of integration of the magnetoresistive element while having high magnetic properties. The method includes: preparing a stacked film including one of the two magnetic layers, a layer to form the tunnel barrier layer, and the other of the two magnetic layers, on a substrate; forming multiple separated stacked films on the substrate by separating the stacked film into the multiple stacked films by etching; irradiating side portions of the multiple separated stacked films with ion beams in a pressure-reducible process chamber; and after the irradiation with the ion beams, forming oxide layers or nitride layers on surfaces of the multiple stacked films by introducing an oxidizing gas or a nitriding gas into the process chamber.

1 . A method of manufacturing a magnetoresistive element in which a tunnel barrier layer is provided between two magnetic layers, the method comprising the steps of:
 preparing a stacked film on a substrate, the stacked film including one of the two magnetic layers, a layer to form the tunnel barrier layer, and the other of the two magnetic layers;   forming a plurality of separated stacked films on the substrate by separating the stacked film into the plurality of stacked films by etching;   irradiating side portions of the plurality of separated stacked films with ion beams in a pressure-reducible process chamber; and   after the irradiation with the ion beams, forming oxide layers or nitride layers on surfaces of the plurality of stacked films by introducing an oxidizing gas or a nitriding gas into the process chamber.   
     
     
         2 . The method of manufacturing a magnetoresistive element according to  claim 1 , wherein the etching is reactive ion etching. 
     
     
         3 . The method of manufacturing a magnetoresistive element according to  claim 1 , wherein the etching is performed by irradiation with the ion beams. 
     
     
         4 . The method of manufacturing a magnetoresistive element according to  claim 1 , wherein the irradiation with the ion beams involves generating plasma by using an inert gas. 
     
     
         5 . The method of manufacturing a magnetoresistive element according to  claim 4 , wherein the oxidizing gas or the nitriding gas is introduced together with the inert gas. 
     
     
         6 . The method of manufacturing a magnetoresistive element according to  claim 4 , wherein the oxidizing gas or the nitriding gas is introduced after completion of the generating of the plasma. 
     
     
         7 . The method of manufacturing a magnetoresistive element according to  claim 1 , wherein the oxidizing gas or the nitriding gas is set at a partial pressure within a range of 1.0×10 −1  Pa to 2.0×10 −3  Pa. 
     
     
         8 . The method of manufacturing a magnetoresistive element according to  claim 1 , wherein the oxide layers or the nitride layers each have a layer thickness within a range of 1.5 nm to 3.0 nm. 
     
     
         9 . The method of manufacturing a magnetoresistive element according to  claim 1 , further comprising the step of forming a protection layer on the oxide layers or the nitride layers. 
     
     
         10 . The method of manufacturing a magnetoresistive element according to  claim 9 , wherein the protection layer is a nitride film. 
     
     
         11 . The method of manufacturing a magnetoresistive element according to  claim 1 , wherein the layer to form the tunnel barrier layer contains Al 2 O 3  or MgO. 
     
     
         12 . A manufacturing system for a magnetoresistive element in which a tunnel barrier layer is provided between two magnetic layers, the system comprising:
 an etching apparatus including an etching chamber and configured to separate a stacked film, which includes one of the two magnetic layers, a layer to form the tunnel barrier layer, and the other of the two magnetic layers, on a substrate into a plurality of stacked films by etching inside the etching chamber, and thereby to form the plurality of separated stacked films on the substrate; and   an ion beam irradiation apparatus including a pressure-reducible process chamber connected to the etching chamber via a substrate transfer chamber, and configured to irradiate side portions of the plurality of separated stacked films with ion beams in the process chamber, wherein   the ion beam irradiation apparatus includes a gas introduction system configured to introduce an oxidizing gas or a nitriding gas into the process chamber after the irradiation with the ion beams.