Thin film, method for manufacturing thin film, and electronic component

Abstract

A method for manufacturing a thin film is performed such that the internal stress is controlled while the preferred orientation property is maintained at a high value. An AlN piezoelectric thin film is formed on a substrate by a sputtering method using a mixed gas including Ar and nitrogen, wherein the mixed gas has a nitrogen flow rate ratio, that is, nitrogen flow rate relative to the sum of the Ar flow rate and the nitrogen flow rate, of about 10% to about 75%.

What is claimed is:  
     
         1 . A thin film comprising: 
 an AlN material provided on a surface of a substrate, wherein the crystallinity is the C axis preferred orientation, the half-width of a rocking curve is about 1.4° to about 1.6°, and an internal stress is within the range of approximately ±1 GPa.    
     
     
         2 . The thin film according to  claim 1 , wherein the thin film is one of a piezoelectric thin film, a dielectric thin film and a magnetic material thin film.  
     
     
         3 . An electronic component comprising: 
 a substrate; and    a thin film disposed on the substrate and made of an AlN material, wherein the crystallinity is the C axis preferred orientation, the half-width of a rocking curve is about 1.4° to about 1.6°, and an internal stress is within the range of approximately ±1 GPa.    
     
     
         4 . The electronic component according to  claim 3 , wherein the substrate is made of Si.  
     
     
         5 . The electronic component according to  claim 3 , further comprising a thin film made of one SiO 2 , Si 3 N 4 , and Al 2 O 3 , a lower layer electrode , the thin film, and an upper layer electrode arranged in this order.  
     
     
         6 . The electronic component according to  claim 3 , wherein a diaphragm is provided on the substrate.  
     
     
         7 . The electronic component according to  claim 3 , wherein the electronic component is one of a piezoelectric thin film resonator, a filter, a sensor, and an actuator.  
     
     
         8 . A method for manufacturing a thin film comprising the steps of: 
 providing a substrate; and    forming a thin film on the substrate using a mixed gas of Ar and nitrogen such that the thin film includes an AlN material, wherein the crystallinity is the C axis preferred orientation, the half-width of a rocking curve is about 1.4° to about 1.6°, and an internal stress is within the range of approximately ±1 GPa;    wherein said mixed gas has a nitrogen flow rate ratio of about 10% to about 75%, wherein the nitrogen flow rate is a ratio of a nitrogen flow rate relative to the sum of an Ar flow rate and the nitrogen flow rate.    
     
     
         9 . The method according to  claim 8 , wherein the thin film is formed via a sputtering process.  
     
     
         10 . The method according to  claim 8 , wherein the thin the AlN piezoelectric thin film is formed at a temperature of the substrate of approximately 100° C., with an RF power of about 100 W, and at a nitrogen flow rate ratio of about 5% to about 90%.  
     
     
         11 . The method according to  claim 8 , wherein the thin film is one of a piezoelectric thin film, a dielectric thin film and a magnetic material thin film.  
     
     
         12 . The method according to  claim 8 , wherein the substrate is made of Si.  
     
     
         13 . The method according to  claim 8 , further comprising the steps of forming a thin film made of one SiO 2 , Si 3 N 4 , and Al 2 O 3 , a lower layer electrode, forming the thin film, and an upper layer electrode arranged in this order.  
     
     
         14 . The method according to  claim 8 , further comprising the step of forming a diaphragm on the substrate.  
     
     
         15 . An electronic component comprising a thin film manufactured according to the method of  claim 8 .  
     
     
         16 . The electronic component according to  claim 15 , wherein the electronic component is one of a piezoelectric thin film resonator, a filter, a sensor, and an actuator.