Sputtering apparatus, film deposition method, and control device

Abstract

A sputtering apparatus according to one embodiment of the present invention includes a substrate holder, a cathode unit arranged at a position diagonally opposite to the substrate holder, a position sensor for detecting a rotational position of the substrate, and a holder rotation controller for adjusting a rotation speed of the substrate according to the detected rotational position. The holder rotation controller controls the rotation speed so that the rotation speed of the substrate when the cathode unit is located on a side in a first direction as an extending direction of a process target surface of the relief structure is lower than the rotation speed of the substrate when the cathode unit is located on a side in a second direction which is perpendicular to the first direction along the rotation of the substrate.

1 . A sputtering apparatus comprising:
 a substrate holder configured to rotatably hold a substrate;   a target holder arranged at a position diagonally opposite to the substrate holder, and configured to support at least one sputtering target;   a position detecting means for detecting a rotational position of the substrate held on the substrate holder; and   a rotation control means for adjusting a rotation speed of the substrate according to the rotational position detected by the position detecting means,   wherein, when the substrate having at least one relief structure formed thereon is placed on the substrate holder, the rotation control means controls the rotation speed of the substrate so that the rotation speed of the substrate when the sputtering target to be deposited is located on a side in a first direction which is parallel to a side surface as a process target surface of the relief structure and is parallel to an in-plane direction of the substrate is lower than the rotation speed of the substrate when the sputtering target to be deposited is located on a side in a second direction which is perpendicular to the first direction and is parallel to the in-plane direction of the substrate.   
     
     
         2 . The sputtering apparatus according to  claim 1 , wherein the rotation control means calculates the rotation speed as a sinusoidal function of a rotation angle of the substrate, and controls the rotation speed of the substrate based on the sinusoidal function. 
     
     
         3 . The sputtering apparatus according to  claim 2 , wherein the rotation control means controls the rotation speed so that a sinusoidal wave of the rotation speed advances two periods during one rotation of the substrate. 
     
     
         4 . The sputtering apparatus according to  claim 1 , wherein the rotation control means controls the rotation speed so that the rotation speed takes on a maximum value when the side surface as the process target surface is perpendicular to a plane containing a line segment which links a center of the sputtering target to be deposited and a center of rotation of the substrate holder, the plane being perpendicular to a surface of the substrate on which the relief structure is formed, and so that the rotation speed takes on a minimum value when the substrate is rotated 90° from when the side surface as the process target surface is perpendicular to the plane. 
     
     
         5 . The sputtering apparatus according to  claim 1 , wherein the relief structure is a wave-shaped relief structure having a periodic waveform in cross section, and adjacent wave-shaped relief structures are arranged with their longitudinal directions aligned substantially parallel to each other. 
     
     
         6 . The sputtering apparatus according to  claim 5 , wherein the wave-shaped relief structure has one or more waveforms selected from the group consisting of a sinusoidal waveform, a rectangular waveform, a triangular waveform, and a trapezoidal waveform. 
     
     
         7 . The sputtering apparatus according to  claim 5 , wherein the rotation control means controls the rotation speed so that the rotation speed takes on a maximum value when the longitudinal direction of the wave-shaped relief structure is perpendicular to a plane containing a line segment which links a center of the sputtering target to be deposited and a center of rotation of the substrate holder, the plane being perpendicular to a surface of the substrate on which the relief structure is formed, and so that the rotation speed takes on a minimum value when the substrate is rotated 90° from when the longitudinal direction of the wave-shaped relief structure is perpendicular to the plane. 
     
     
         8 - 21 . (canceled) 
     
     
         22 . The sputtering apparatus according to  claim 1 , further comprising: a cathode unit provided integrally with or separately from the target holder, and configured to sputter the sputtering target. 
     
     
         23 . The sputtering apparatus according to  claim 22 , wherein
 a plurality of the cathode units and a plurality of the sputtering targets are arranged around an axis of rotation of the substrate holder, and   a multilayered film is deposited on the substrate by applying a voltage sequentially or alternately to the individual cathode units.   
     
     
         24 . The sputtering apparatus according to  claim 22 , wherein
 the cathode unit is a cathode unit having a polygonal prism structure, and the sputtering target is placeable on each side surface of the cathode unit having the polygonal prism, and   a multilayered film is deposited on the substrate by sequentially or alternately rotating the cathode unit having the polygonal prism structure.   
     
     
         25 . The sputtering apparatus according to  claim 22 , wherein
 the cathode unit is a target holder having a polygonal prism structure, and the sputtering target is placeable on each side face of the target holder having the polygonal prism structure,   an ion beam source configured to irradiate the sputtering target with an ion beam is arranged at a position diagonally opposite to the target holder having the polygonal prism structure, and different from the substrate holder, and   a multilayered film is deposited on the substrate by sequentially or alternately rotating the target holder having the polygonal prism structure.   
     
     
         26 - 32 . (canceled) 
     
     
         33 . A film deposition method using sputtering, comprising the steps of:
 placing a substrate having at least one relief structure formed thereon, on a rotatable substrate holder; and   forming a film on a process target surface of the relief structure by sputtering a sputtering target arranged at a position diagonally opposite to the substrate, while rotating the substrate,   wherein the step of forming includes forming the film so that the amount of deposition on a side surface as the process target surface is relatively large when the sputtering target to be deposited is located on a side in a first direction which is parallel to the side surface as the process target surface of the relief structure on the substrate and is parallel to an in-plane direction of the substrate, and so that the amount of deposition on the side surface as the process target surface is relatively small when the sputtering target to be deposited is located on a side in a second direction which is perpendicular to the first direction and is parallel to the in-plane direction of the substrate.   
     
     
         34 . A film deposition method using sputtering, comprising the steps of:
 placing a substrate having at least one relief structure formed thereon, on a rotatable substrate holder; and   forming a film on a process target surface of the relief structure by sputtering a sputtering target arranged at a position diagonally opposite to the substrate, while rotating the substrate,   wherein the step of forming includes the steps of:   detecting a rotational position of the substrate; and   adjusting a rotation speed of the substrate according to the detected rotational position, and   the step of adjusting includes controlling the rotation speed of the substrate so that the rotation speed of the substrate when the sputtering target to be deposited is located on a side in a first direction which is parallel to a side surface as the process target surface of the relief structure on the substrate and is parallel to an in-plane direction of the substrate is lower than the rotation speed of the substrate when the sputtering target to be deposited is located on a side in a second direction which is perpendicular to the first direction and is parallel to the in-plane direction of the substrate.   
     
     
         35 - 36 . (canceled) 
     
     
         37 . A control device for controlling a sputtering apparatus including
 a substrate holder configured to rotatably hold a substrate;   a target holder arranged at a position diagonally opposite to the substrate holder, and configured to support at least one sputtering target;   a position detecting means for detecting a rotational position of the substrate held on the substrate holder; and   a rotation driving means for controlling rotation of the substrate holder,   the control device comprising:   means for acquiring information on the rotational position from the position detecting means;   means for generating a control signal to control the rotation driving means according to the acquired information on the rotational position, when the substrate having at least one relief structure formed thereon is placed on the substrate holder, in such a manner that the rotation speed of the substrate when the sputtering target to be deposited is located on a side in a first direction which is parallel to a side surface as a process target surface of the relief structure and is parallel to an in-plane direction of the substrate is lower than the rotation speed of the substrate when the sputtering target to be deposited is located on a side in a second direction which is perpendicular to the first direction and is parallel to the in-plane direction of the substrate; and   means for transmitting the generated control signal to the rotation driving means.   
     
     
         38 - 45 . (canceled)