Thin read gap magnetoresistive (MR) sensor element and method for fabrication thereof

A dual stripe magnetoresistive (DSMR) sensor element maintaining attenuated read gap thickness while having attenuated leakage between successive pairs of conductor lead layers and between a pair of conductor lead layers and a blanket second shield comprising:

• a substrate;
• a first shield layer formed over the substrate;
• a first dielectric spacer layer formed upon the first shield layer;
• a patterned first magnetoresistive (MR) layer formed upon the first dielectric spacer layer, said first magnetoresistive (MR) layer being patterned by use of a first novel lift off stencil;
• a pair of patterned first longitudinal magnetic biasing layers formed adjacent to and covering a pair of opposite ends of the patterned first magnetoresistive (MR) layer, said magnetic biasing layer being formed by using the same said first novel lift off stencil;
• a pair of patterned first conductor lead layers formed adjacent to and communicating electrically with a pair of opposite ends of the patterned first magnetoresistive (MR) layer to define a trackwidth of the patterned first magnetoresistive (MR) layer said patterned conductor lead layers being formed by using the same first novel lift off stencil;
• a pair of patterned second dielectric spacer layers being formed over the said patterned conductor lead layers, and extending over opposite ends of the patterned first magnetoresistive (MR) layer but not completely covering said patterned first magnetoresistive (MR) layer, said dielectric spacer layers being formed by using the same first novel lift off stencil;
• a blanket third dielectric spacer layer formed upon the pair of patterned second dielectric layers and the patterned first magnetoresistive (MR) layer at the first trackwidth of the patterned first magnetoresistive (MR) layer;
• a patterned second magnetoresistive layer formed upon the blanket third dielectric spacer layer, said second magnetoresistive (MR) layer being patterned by use of a second novel lift off stencil;
• a pair of patterned second longitudinal magnetic biasing layers formed adjacent to and covering a pair of opposite ends of the patterned second magnetoresistive (MR) layer, said patterned magnetic biasing layers being formed by using the same said second novel lift off stencil;
• a pair of patterned second conductor lead layers formed adjacent to and communicating electrically with a pair of opposite ends of the patterned second magnetoresistive (MR) layer to define a second trackwidth of the patterned second magnetoresistive (MR) layer, said second conductor lead layers being patterned by use of the same said second novel lift off stencil, where a sum of the thicknesses of the blanket third dielectric spacer layer plus the patterned second dielectric layer separating a patterned first conductor lead layer within the pair of patterned first conductor lead layers from a patterned second conductor lead layer within the pair of patterned second conductor lead layers is greater than a single thickness of the blanket third dielectric spacer layer separating the patterned first magnetoresistive (MR) layer within the first trackwidth of the patterned first magnetoresistive (MR) layer from the patterned second magnetoresistive (MR) layer within the second trackwidth of the patterned second magnetoresistive (MR) layer;
• a blanket fifth dielectric spacer layer spacer layer formed upon the pair of patterned fourth dielectric layers and upon the patterned second magnetoresistive (MR) layer at the trackwidth of the patterned second magnetoresistive (MR) layer;
• and
• a second shield layer formed upon the blanket fifth dielectric spacer layer, where a sum of the thicknesses of the blanket fifth dielectric spacer layer plus the fourth patterned dielectric layer separating a second patterned conductor lead layer within a pair of second patterned conductor lead layers from the second shield layer is greater than a single thickness of the blanket fifth dielectric spacer layer separating the patterned second magnetoresistive (MR) layer from the second shield layer within the trackwidth of the patterned second magnetoresistive (MR) layer.

A method for forming a magnetoresistive (MR) sensor element comprising:

• providing a substrate;
• forming over the substrate a first shield layer;
• forming upon the first shield layer a first dielectric spacer layer;
• forming upon the first dielectric spacer layer a (patterned) magnetoresistive (MR) layer;
• forming upon the magnetoresistive (MR) layer a blanket first release layer;
• forming upon the blanket first release layer a blanket first photoresist layer;
• photoexposing and developing the blanket first photoresist layer to provide a remaining portion of the blanket first photoresist layer having a width approximating the desired trackwidth of the magnetoresistive (MR) sensor element;
• etching the blanket first release layer, using the remaining first photoresist layer as an etch mask, to provide a symmetric overhang of the remaining first photoresist layer over the blanket first release layer and providing, thereby, a lift off stencil;
• employing the lift off stencil as an etch mask to pattern and etch the magnetoresistive (MR) layer;
• employing the lift off stencil as a deposition mask to form a pair of longitudinal magnetic biasing layers adjacent to and covering a pair of opposite ends of the patterned second magnetoresistive (MR) layer;
• employing the lift off stencil as a deposition mask to form over said pair of longitudinal magnetic biasing layers adjacent to and communicating electrically with a pair of opposite ends of the patterned magnetoresistive (MR) layer a pair of patterned conductor lead layers to define a trackwidth of the patterned magnetoresistive (MR) layer;
• employing the lift off stencil as a deposition mask to form over said pair of patterned conducting lead layers a pair of patterned second dielectric layers over the said patterned conductor lead layers, and extending over opposite ends of the patterned magnetoresistive (MR) layer but not completely covering said magnetoresistive (MR) layer;
• stripping the lift off stencil, together with any deposition residue remaining upon it, from the patterned magnetoresistive (MR) layer;
• forming upon the pair of patterned second dielectric layers and upon the patterned magnetoresistive (MR) layer at the trackwidth of the patterned magnetoresistive (MR) layer a blanket third dielectric spacer layer spacer layer;
• and
• forming upon the blanket third dielectric spacer layer a second shield layer, where a first thickness of the blanket third dielectric spacer layer separating a patterned conductor lead layer within a pair of patterned conductor lead layers from the second shield layer is greater than a second thickness of the blanket third dielectric spacer layer separating the patterned magnetoresistive (MR) layer from the third shield layer within the trackwidth of the patterned magnetoresistive (MR) layer.

A method for forming a dual stripe magnetoresistive (DSMR) sensor element comprising:

• providing a substrate;
• forming over the substrate a first shield layer;
• forming upon the first shield layer a first dielectric spacer layer;
• forming upon the first dielectric spacer layer a first magnetoresistive (MR) layer;
• forming upon the first magnetoresistive (MR) layer a blanket first release layer;
• forming upon the blanket first release layer a blanket first photoresist layer;
• photoexposing and developing the blanket first photoresist layer to provide a remaining portion of the blanket first photoresist layer having a width approximating the desired first trackwidth of the first magnetoresistive (MR) sensor element;
• etching the blanket first release layer, using the remaining first photoresist layer as an etch mask, to provide a symmetric overhang of the remaining first photoresist layer over the blanket first release layer and providing, thereby, a first lift off stencil;
• employing the first lift off stencil as an etch mask to pattern and etch the first magnetoresistive (MR) layer;
• employing the first lift off stencil as a deposition mask to form adjacent to and communicating electrically with a pair of opposite ends of the patterned first magnetoresistive (MR) layer a pair of patterned first conductor lead layers to define a first trackwidth of the patterned first magnetoresistive (MR) layer;
• employing the first lift off stencil as a deposition mask to form over said pair of patterned first conducting lead layers a pair of patterned second dielectric layers over the said patterned conductor lead layers, and extending over opposite ends of the patterned first magnetoresistive (MR) layer but not completely covering said patterned first magnetoresistive (MR) layer;
• removing the first lift off stencil together with any deposition remnants upon it from the first patterned magnetoresistive layer;
• forming upon the pair of patterned second dielectric layers and upon the patterned first magnetoresistive (MR) layer at the first trackwidth of the patterned first magnetoresistive (MR) layer a blanket third dielectric spacer layer;
• forming upon the blanket third dielectric spacer layer a (patterned) second magnetoresistive layer;
• forming upon the second magnetoresistive (MR) layer a blanket second release layer;
• forming upon the blanket third release layer a blanket second photoresist layer;
• photoexposing and developing the blanket second photoresist layer to provide a remaining portion of the blanket second photoresist layer having a width approximating the desired first trackwidth of the second magnetoresistive (MR) sensor element;
• etching the blanket second release layer, using the remaining second photoresist layer as an etch mask, to provide a symmetric overhang of the remaining second photoresist layer over the second release layer and providing, thereby, a second lift off stencil;
• employing the second lift off stencil as an etch mask to pattern and etch the second magnetoresistive (MR) layer;
• employing the second lift off stencil as a deposition mask to form a pair of second longitudinal magnetic biasing layers adjacent to and covering a pair of opposite ends of the patterned second magnetoresistive (MR) layer;
• employing the second lift off stencil to form adjacent to and communicating electrically with a pair of opposite ends of the patterned second magnetoresistive layer a pair of second conductor lead layers to define a second trackwidth of the patterned second magnetoresistive (MR) layer, where a sum of the thicknesses of the blanket third dielectric spacer layer plus the patterned second dielectric spacer layers separating a patterned first conductor lead layer within the pair of patterned first conductor lead layers is greater than a single thickness of the blanket third dielectric spacer layer separating the patterned first magnetoresistive (MR) layer within the first trackwidth of the patterned first magnetoresistive (MR) layer from the patterned second magnetoresistive (MR) layer within the second trackwidth of the patterned second magnetoresistive (MR) layer;
• employing the lift off stencil as a deposition mask to form over said pair of patterned second conducting lead layers a pair of patterned fourth dielectric layers over the said patterned second conductor lead layers, and extending over opposite ends of the patterned second magnetoresistive (MR) layer but not completely covering said second magnetoresistive (MR) layer;
• stripping away the second lift off stencil together with any deposition remnant upon it;
• forming upon the pair of patterned fourth dielectric layers and upon the patterned second magnetoresistive (MR) layer at the trackwidth of the patterned second magnetoresistive (MR) layer a blanket fifth dielectric spacer layer spacer layer;
• and
• forming upon the blanket fifth dielectric spacer layer a second shield layer, where a sum of the thicknesses of the blanket fifth dielectric spacer layer plus the fourth patterned dielectric layer separating a second patterned conductor lead layer within a pair of second patterned conductor lead layers from the second shield layer is greater than a single thickness of the blanket fifth dielectric spacer layer separating the patterned second magnetoresistive (MR) layer from the second shield layer within the trackwidth of the patterned second magnetoresistive (MR) layer.