Fingerprint sensor including an anisotropic dielectric coating and associated methods

A sensor comprising:

• an integrated circuit die comprising at least one conductive layer defining an array of electric field sensing electrodes and a plurality of capacitive coupling pads;
• and
• a dielectric covering adjacent the array of electric field sensing electrodes and said capacitive coupling pads of said integrated circuit die, said dielectric covering comprising a z-axis anisotropic dielectric layer for focussing an electric field at each of the electric field sensing electrodes and for reducing cross-talk between adjacent capacitive coupling pads, the z-axis being normal to the at least one conductive layer.

A integrated circuit comprising:

• an integrated circuit die comprising at least one conductive layer defining a plurality of capacitive coupling pads;
• and
• a dielectric covering adjacent said capacitive coupling pads of said integrated circuit die, said dielectric covering comprising a z-axis anisotropic dielectric layer for reducing cross-talk between adjacent capacitive coupling pads, the z-axis being normal to the at least one conductive layer.

A integrated circuit comprising:

• an integrated circuit die;
• and
• a dielectric covering adjacent said integrated circuit die, said dielectric covering comprising a z-axis anisotropic dielectric layer, the z-axis being normal to the integrated circuit die.

A method for making a fingerprint sensor comprising the steps of:

• forming an integrated circuit die comprising at least one conductive layer defining an array of electric field sensing electrodes for sensing a fingerprint;
• and
• forming a dielectric covering adjacent the array of electric field sensing electrodes of the integrated circuit die and for contact by a finger, the dielectric covering comprising a z-axis anisotropic dielectric layer for focussing an electric field at each of the electric field sensing electrodes, the z-axis being normal to the at least one conductive layer.

A method of making an integrated circuit comprising:

• providing an integrated circuit die;
• and
• forming a dielectric covering adjacent the integrated circuit die, the dielectric covering comprising a z-axis anisotropic dielectric layer, the z-axis being normal to the integrated circuit die.