Ion beam fast parallel scanning having dipole magnetic lens with nonuniform field

Claim 2

Apparatus for providing a parallel scanned ion beam, said apparatus comprising A. a source of an ion beam, B. deflecting means for deflecting said ion beam to provide a deflected ion beam, and C. dipole magnetic lens means for establishing a nonuniform magnetic field for deflecting said deflected ion beam to provide a scanned ion beam characterized by a contiguous array of parallel trajectories after emerging from said dipole magnetic lens means, said dipole magnetic lens means comprising a pair of magnetic poles, each of rectangular cross section in planes parallel to a beam plane including the scanned ion beam, and defining between said poles a gap of variable width in a plane perpendicular to the beam plane.

Claim 3

In ion beam apparatus for semiconductor apparatus and having (i) an ion beam source, (ii) first deflection means for deflecting the ion beam to a scanning beam having diverging ion trajectories, and (iii) second deflection means for deflecting the scanning diverging ion trajectories to a scanning beam having substantially parallel ion trajectories extending along a first axis and in a plane defined by said first axis and a second axis transverse thereto, the improvement in which said second deflection means comprises A. a pair of magnetic poles having opposed surfaces defining therebetween a gap through which the diverging ion trajectories pass, B. said magnetic poles defining said gap to have a substantially uniform length dimension along said first axis and to have a selected width dimension, between the poles, that varies with position along said second axis, wherein said second axis is transverse to said gap width. C. whereby said magnetic poles develop in the gap a magnetic field that is substantially uniform along said first axis and that varies selectively along said second axis.

Claim 4

In ion beam apparatus for semiconductor apparatus and having (i) an ion beam source, (ii) first deflection means for deflecting the ion beam to a scanning beam having diverging ion trajectories, and (iii) second deflection means for deflecting the scanning diverging ion trajectories to a scanning beam having substantially parallel ion trajectories extending along a first axis and in a plane defined by said first axis and a second axis transverse thereto, the improvement in which said second deflection means comprises A. a pair of magnetic poles having opposed surfaces defining therebetween a gap through which the diverging ion trajectories pass, B. said magnetic poles defining said gap to have a substantially uniform length dimension along said first axis and to have a selected width dimension, between the poles, that varies with position along said second axis, wherein said second axis is transverse to said gap width. C. whereby said magnetic poles develop in the gap a magnetic field that is substantially uniform along said first axis and that varies selectively along said second axis.

Claim 5

In ion beam apparatus according to claim 2, the further improvement wherein each said pole piece has a substantially rectangular shape in the plane defined by said first and second axes.

Claim 6

In ion beam apparatus according to claim 3, the further improvement wherein each said pole piece is oriented with one side of said rectangular shape parallel to said first axis and with a further side extending parallel to said second axis.

Claim 7

In ion beam apparatus according to claim 2, the further improvement wherein said magnetic poles define said gap to have the uniform gap width at any point along said first axis.

Claim 10

A method according to claim 6 having the further step of configuring each pole piece to have a substantially rectangular cross section in a plane parallel to said first and second axes and oriented with different sides of the rectangular shape parallel respectively to each of said first and second axis.

Claim 11

Apparatus according to claim 1 further comprising means for substantially confining the magnetic field between said pair of poles to be within said gap.

Claim 12

Apparatus according to claim 1 further comprising field clamping means for maintaining the effective field boundary of the magnetic field between said pair of poles to have a substantially fixed known position.

Claim 13

In ion beam apparatus according to claim 4, the further improvement comprising field clamping means for substantially confining the magnetic field between said pair of magnetic poles to have a substantially known effective field boundary.

Claim 14

A method according to claim 6 comprising the further step of substantially confining the magnetic field between said pair of poles to have an effective field boundary at a substantially known position.