US 2016/0104607 A1 · METHOD OF AND MAGNET ASSEMBLY FOR HIGH POWER PULSED MAGNETRON SPUTTERING

Abstract

A magnet assembly for use in high power pulsed magnetron sputtering comprises a configuration of magnets having a magnetic field topology comprising magnetic field components Bx, By and Bz. A tangential magnetic field B// distribution on an x-y plane above the configuration of magnets comprising an outer continuous ring and one or more inner continuous rings contained in the outer continuous ring. A total magnetic field Btot distribution on an x-z plane intersecting the configuration of magnets comprises an outer closed loop and one or more inner closed loops contained in the outer closed loop, where, as a function of x, a tangential magnetic field B// alternates between (a) high field values greater than 200 G and high gradients in the z-direction of at least 1000 G/in, and (b) low field values of less than 50 G and low gradients in the z-direction of at most 250 G/in.

Claims28

Dependent claims

A magnet assembly for use in high power pulsed magnetron sputtering, the magnet assembly comprising:

a configuration of magnets having a magnetic field topology comprising magnetic field components Bx, By and Bz, where x- and y-directions are parallel to the configuration of magnets and a z-direction is normal to the configuration of magnets,
wherein a tangential magnetic field B// distribution on an x-y plane above the configuration of magnets comprises an outer continuous ring and one or more inner continuous rings contained in the outer continuous ring, and
wherein a total magnetic field Btot distribution on an x-z plane intersecting the configuration of magnets comprises an outer closed loop and one or more inner closed loops contained in the outer closed loop, where, as a function of x, a tangential magnetic field B// alternates between (a) high field values greater than 200 G and high gradients in the z-direction of at least 1000 G/in, and (b) low field values of less than 50 G and low gradients in the z-direction of at most 250 G/in.

A method of high power pulsed magnetron sputtering, the method comprising:

positioning a backside of a sputtering target adjacent to a configuration of magnets in a vacuum chamber, a front surface of the sputtering target being positioned in opposition to a workpiece to be coated;
generating a pulsed plasma at the front surface of the sputtering target at a pulsed voltage of at least about 400 V for a pulse length of at least about 10 microseconds to remove atoms from the sputtering target;
and
during generation of the pulsed plasma,
(1) retaining a current density on at least a portion of the front surface of the sputtering target of at least about 100 mA/cm2 in order to ionize at least some of the atoms removed from the sputtering target, thereby generating a sufficient current to sustain the pulsed plasma, and
(2) creating an ionization zone between the pulsed plasma and the workpiece away from the front surface of the sputtering target, the ionization zone having a sufficient electron density and temperature to ionize an additional fraction of the atoms removed from the sputtering target and having a sufficiently low electric field to allow ionized atoms created therein to transit to the workpiece for deposition at a high rate.

3 more elements

Dependencies are inferred from the claim text.

Method of and magnet assembly for high power pulsed magnetron sputtering

Life of this patent

Method of and magnet assembly for high power pulsed magnetron sputtering

Life of this patent

Abstract

Claims28