Patent ID: 11906291
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G  C  H  B | IPC G  H

Claim 0:
1. A method of measuring a thickness of a graphene layer directly grown on a silicon substrate, by using an X-ray photoelectron spectroscopy (XPS) instrument, the method comprising:
emitting X-ray radiation toward the graphene layer directly grown on the silicon substrate using a source on the XPS instrument;
obtaining signal intensities from the graphene layer directly grown on the silicon substrate in response to emitting the X-ray radiation toward the graphene layer directly grown on the silicon substrate using a sensor on the XPS instrument; and
calculating the thickness tG of the graphene layer according to an equation below,, t
      G
    
    =
    
      
        λ
        
          E
          ⁢
          A
          ⁢
          L
        
      
      ⁢
      cos
      ⁢
      
        
      
      ⁢
      α
      ⁢
      
        
      
      ⁢
      ln
      ⁢
      
        
      
      ⁢
      
        (
        
          
            
              R
              exp
            
            
              R
              0
            
          
          +
          1
        
        )
      
    
  

  
    
      
        wherein
        ⁢
        
          
        
        ⁢
        
          R
          0
        
      
      =
      
        
          I
          
            c
            ⁢
            o
          
        
        
          I
          
            s
            ⁢
            i
            ⁢
            o
          
        
      
    
    ,
    
      
        R
        exp
      
      =
      
        
          I
          C
        
        
          I
          
            s
            ⁢
            i
          
        
      
    
    ,
  

λREAL is an effective attenuation length,
α is a detection angle for the XPS instrument,
Ico is a signal intensity of a photoelectron beam emitted from bulk-type graphene,
Isio is a signal intensity of a photoelectron beam emitted from bulk-type silicon,
Ic is a signal intensity of a photoelectron beam emitted from the graphene layer and obtained by the sensor on the XPS instrument in response to the graphene layer receiving X-ray radiation by the XPS instrument, and
Isi is a signal intensity of a photoelectron beam emitted from the silicon substrate and obtained by the sensor on the XPS instrument in response to the silicon substrate receiving X-ray radiation by the XPS instrument,
wherein R0 is obtained by a linear relationship between the signal intensity Isi of the photoelectron beam emitted from the silicon substrate and the signal intensity Ic of the photoelectron beam emitted from the graphene layer using the XPS instrument.