High density thin film register

Claim 2

An improved geometry for a straight line thin film element for use in storing and propagating domains in thin film registers comprising; a straight constant coercivity portion adapted to store a plurality of domains for selected propagation therealong, wherein the straight strip portion comprises, a single continuous film of magnetic material of constant coercivity disposed on a substrate, with the easy axis extending parallel with the length of the strip portion, the constant coercivity portion having a a selected film thickness T, constant coercive force Hc, and a selected width corresponding to a domain width, wherein the domains have a width to length ratio W/L of the order of from two through one twenty-fourth with a maximum length L of the order of 6 mils, wherein the above parameters provide an operational margin HN-HW within a selected range of values commensurate with the value of Hdrive, HW equals the nucleation field and is greater than Hdrive, HW equals the domain wall threshold field and is less than Hdrive, and Hdrive equals the drive field applied to provide domain wall motion.

Claim 3

The thin film element of claim 1 wherein HN-HW is of the order of from 2 to 20 oersteds, the length L of the domain is less than 6 mils, the width W of the domains and of the strip is less than 2 mils, and the associated ratio W/L is of the order of from two to one twenty-fourth.

Claim 4

The thin film element of claim 1 including a second continuous thin film disposed relative to the first film to define a pair of continuous straight superimposed thin films of magnetic material, a conductor material disposed between the pair of thin films, wherein the thin films are magnetically closed along their lateral edges to define a closed flux structure of constant coercivity having said W/L ratio.

Claim 5

The thin film element of claim 3 wherein the thin films of magnetic materials have the easy axis extending substantially transverse to the lengths thereof.

Claim 6

An improved magnetic thin film memory for storing and propagating a large plurality of magnetic domains at relatively large packing densities the combination comprising; a plurality of straight continuous flat strips of magnetic material each including a continuous straight constant coercivity portion adapted to store a plurality of domains for selected propagation therealong, with the easy axis extending parallel with the lengths of the strip portions the constant coercivity portions each having a selected film thickness T, constant coercive force Hc, and a selected width corresponding to a domain width; said domains having a width to length ratio W/L of the order of from two through one twenty-fourth with a maximum width of the order of 2 mils and a maximum length L of the order of 6 mils; wherein the above parameters provide an operational margin HN-HW within a selected range of values commensurate with the value of Hdrive, wherein HN equals the nucleation field and is greater than Hdrive, HW equals the domain wall threshold field and is less than Hdrive, and Hdrive equals the drive field applied to provide domain wall motion; nucleating means including a nucleating conductor magnetically coupled to one end of each strip to selectively generate a succession of magnetic domains in each; anD drive means including a series of parallel drive conductors disposed substantially perpendicular across the strips of magnetic material in magnetic field bridging relation therewith for applying an associated series of propagating fields along the strips to selectively propagate the plurality of domains therealong.

Claim 7

An improved magnetic thin film memory for storing and propagating a large plurality of magnetic domains at relatively large packing densities the combination comprising; a plurality of straight continuous flat strips of magnetic material each including a continuous straight constant coercivity portion adapted to store a plurality of domains for selected propagation therealong, with the easy axis extending parallel with the lengths of the strip portions the constant coercivity portions each having a selected film thickness T, constant coercive force Hc, and a selected width corresponding to a domain width; said domains having a width to length ratio W/L of the order of from two through one twenty-fourth with a maximum width of the order of 2 mils and a maximum length L of the order of 6 mils; wherein the above parameters provide an operational margin HN-HW within a selected range of values commensurate with the value of Hdrive, wherein HN equals the nucleation field and is greater than Hdrive, HW equals the domain wall threshold field and is less than Hdrive, and Hdrive equals the drive field applied to provide domain wall motion; nucleating means including a nucleating conductor magnetically coupled to one end of each strip to selectively generate a succession of magnetic domains in each; anD drive means including a series of parallel drive conductors disposed substantially perpendicular across the strips of magnetic material in magnetic field bridging relation therewith for applying an associated series of propagating fields along the strips to selectively propagate the plurality of domains therealong.