HIGH-FREQUENCY SPUTTERING DEVICE

• US 20100213047A1
• Filed: 03/19/2010
• Published: 08/26/2010
• Est. Priority Date: 10/04/2007
• Status: Active Grant

• Current Assignee: Canon Anelva Corporation (Canon Inc.)
• Original Assignee: Canon Anelva Corporation (Canon Inc.)
• Inventors: Nakamura, Kanto, Tsunekawa, Koji, Nagamine, Yoshinori
• Granted Patent: US 9,017,535 B2
• Time in Patent Office: Days
• US Class Current: 204/192.120
• CPC Class Codes: C23C 14/081 of aluminium, magnesium or beryllium
• CPC Class Codes: C23C 14/225 Oblique incidence of vaporised material on substrate
• CPC Class Codes: C23C 14/345 using substrate bias
• CPC Class Codes: C23C 14/3464 using more than one target C23C14/56 takes precedence
• CPC Class Codes: C23C 14/352 using more than one target C23C14/56 takes precedence
• CPC Class Codes: C23C 14/50 Substrate holders
• CPC Class Codes: C23C 16/4586 Elements in the interior of the support, e.g. electrodes, heating or cooling devices
• CPC Class Codes: H01J 37/3417 Arrangements
• CPC Class Codes: H01J 37/3438 Electrodes other than cathode
• CPC Class Codes: H01J 37/3444 Associated circuits
• CPC Class Codes: H10N 50/01 Manufacture or treatment

Abstract

Provided is a high-quality magnetoresistive thin film by using a method of controlling self bias of a high-frequency sputtering device. In order to control the self bias for the substrate by adjusting a substrate potential, the high-frequency sputtering device according to the present invention includes: a chamber; evacuation means for evacuating the inside of the chamber; gas introduction means for supplying a gas into the chamber; a substrate holder provided with a substrate mounting table; rotation drive means capable of rotating the substrate holder; a sputtering cathode provided with a target mounting table and arranged such that the surface of the target mounting table is non-parallel to the surface of the substrate mounting table; an electrode disposed inside the substrate holder; and a variable impedance mechanism electrically connected to the electrode, for adjusting the substrate potential on the substrate holder.

Claims

1. A high-frequency sputtering device comprising:

a chamber;

evacuation means for evacuating the inside atmosphere of the chamber;

gas introduction means for supplying a gas into the chamber;

a substrate holder provided with a substrate mounting table;

a rotation drive means for rotating the substrate holder;

a sputtering cathode provided with a target mounting table for sputtering an insulator target on the target mounting table by applying a high-frequency power to the gas to generate a plasma of the gas, the sputtering cathode being arranged such that the surface of the target mounting table is non-parallel to the surface of the substrate mounting table;

a first electrode disposed inside the substrate holder;

a variable impedance mechanism electrically connected to the first electrode, for adjusting a substrate potential;

a second electrode exposed to the plasma;

substrate potential detection means for deriving a potential of the substrate on the basis of DC level in a current from the second electrode; and

a control circuit for controlling the variable impedance mechanism according to the derived substrate potential.

14. A high-frequency sputtering device according to claim 1, wherein:

the second electrode is electrically connected to the first electrode, and a current from the second electrode is incorporated into a current of the first electrode; and

the substrate potential detection means derives a substrate potential on the basis of the DC component of the combined current from the first electrode.

15. A high-frequency sputtering device according to claim 14, wherein

the substrate holder has an opening to expose the first electrode plasma at the opening, and a part of the first electrode at the opening forms the second electrode.

16. A high-frequency sputtering device according to claim 1, wherein

the control circuit has a predetermined optimum value of a substrate potential programmed thereinto, and controls the variable impedance mechanism so that the derived substrate potential becomes the predetermined optimum value of a substrate potential.

17. A high-frequency sputtering device according to claim 1, comprising:

a high-frequency power supply for supplying power to the first electrode;

a detector connected to the high-frequency power supply for detecting an incident wave from the high-frequency power supply and a reflected wave from the electrode; and

a control circuit for controlling the variable impedance mechanism based on the detected incident wave and the reflected wave so that the reflected wave is not detected.

2-13. -13. (canceled)

18. A high-frequency sputtering method for forming a thin film using a high-frequency sputtering device which comprises a chamber;

evacuation means for evacuating the inside atmosphere of the chamber;

gas introduction means for supplying a gas into the chamber;

a substrate holder provided with a substrate mounting table;

rotation drive means for rotating the substrate holder;

a sputtering cathode provided with a target mounting table for sputtering an insulator target on the target mounting table by applying a high-frequency power to the gas to generate a plasma of the gas, the sputtering cathode being arranged such that the surface of the target mounting table is non-parallel to the surface of the substrate mounting table;

a first electrode disposed inside the substrate holder; and

a variable impedance mechanism electrically connected to the first electrode, for adjusting a substrate potential, the method comprising steps of;

disposing a second electrode exposed to the plasma;

deriving a substrate potential on the basis of a DC component of current from the second electrode; and

controlling the variable impedance mechanism according to the derived substrate potential to adjust the substrate potential.

19. A high-frequency sputtering method according to claim 18, wherein:

the second electrode is electrically connected to the first electrode so that a current from the second electrode is incorporated into a current of the first electrode; and

a substrate potential is derived on the basis of DC component of the current of the first electrode.

20. A high-frequency sputtering method according to claim 19, comprising the step of controlling the variable impedance mechanism so that the derived substrate potential becomes a preliminarily programmed optimum substrate potential value.