Methods for fabricating redeposition free thin film CPP read sensors
View Patent ↗Methods are provided for forming current perpendicular to the plane thin film read heads. In one embodiment, the method comprises the steps of forming a lower sensor lead, forming a lower sensor lead cladding of a low sputter yield material on the lower sensor lead, forming a sensor element on the lower sensor lead cladding, and forming an upper sensor lead coupled to the sensor element. The low sputter yield material helps to reduce redeposition of the lower sensor lead material onto side walls of the sensor element as the sensor element is being formed.
1. A method for forming a current perpendicular to the plane thin film read head comprising:
forming a lower sensor lead of an electrically conductive material;
forming a lower sensor lead cladding with an electrically conductive low sputter yield ratio material directly on the lower sensor lead, the low sputter yield ratio material being different from the electrically conductive material of the lower sensor lead;
forming a sensor element on the lower sensor lead cladding after forming the lower sensor lead cladding; and
forming an upper sensor lead coupled to the sensor element.
2. The method of claim 1 wherein forming the lower sensor lead comprises depositing a low resistance material and wherein forming the lower sensor lead cladding comprises depositing a refractory metal.
3. The method of claim 2 wherein forming the sensor element comprises etching to define a pedestal having side walls, and wherein the lower sensor lead cladding inhibits accumulation of sensor lead material on the side walls when defining the pedestal.
4. The method of claim 1 wherein forming the lower sensor lead comprises depositing a low resistance material and wherein forming the lower sensor lead cladding comprises cladding the low resistance material with a material comprising tantalum, titanium, tungsten, molybdenum, zirconium, vanadium, or niobium.
5. The method of claim 4 wherein forming the sensor element comprises etching to define a pedestal having side walls, and wherein the lower sensor lead cladding inhibits accumulation of sensor lead material on the side walls when defining the pedestal.
6. The method of claim 5 wherein depositing the low resistance material comprises depositing a material comprising gold, silver, copper, or aluminum.
7. The method of claim 1 wherein the lower sensor lead cladding is formed with sufficient material to prevent sputtering of underlying lead material.
8. The method of claim 7 wherein forming the sensor element comprises etching to define a pedestal having side walls, and wherein the lower sensor lead cladding inhibits accumulation of sensor lead material on the side walls when defining the pedestal.
9. The method of claim 8 wherein forming the lower sensor lead comprises depositing a low resistance material and wherein forming the lower sensor lead cladding comprises cladding the low resistance material with a refractory metal.
10. The method of claim 8 wherein forming the lower sensor lead comprises depositing a low resistance material and wherein forming the lower sensor lead cladding comprises cladding the low resistance material with a material comprising tantalum, titanium, tungsten, molybdenum, zirconium, vanadium, or niobium.
11. The method of claim 1 wherein the lower sensor lead cladding is not tantalum.
12. The method of claim 1 wherein the lower sensor lead cladding includes titanium.
13. The method of claim 1 wherein the lower sensor lead cladding includes tungsten.
14. The method of claim 1 wherein the lower sensor lead cladding includes molybdenum.
15. The method of claim 1 wherein the lower sensor lead cladding includes zirconium.
16. The method of claim 1 wherein the lower sensor lead cladding includes vanadium.
17. The method of claim 1 wherein the lower sensor lead cladding includes niobium.
18. The method of claim 1 wherein the sensor element is formed by depositing layers of different materials and ion milling the layers to remove excess material of the sensor element.