Integrated circuit with sensor and method of manufacturing such an integrated circuit

A method of manufacturing an integrated circuit, comprising:

• providing a substrate carrying a plurality of circuit elements;
• forming a metallization stack interconnecting the circuit elements, the metallization stack including a patterned upper metallization layer having a first metal portion;
• forming a passivation stack covering the metallization stack, the passivation stack being configured and arranged to mitigate moisture penetration to the metallization stack and ensure operation of the circuit elements;
• forming a trench in the passivation stack to expose the first metal portion;
• forming a via in the trench;
• and
• forming a sensor including a sensing material on the passivation stack over the via to couple the sensing material to the first metal portion,
• wherein the step of forming the passivation stack further includes forming a bond pad portion in the upper metallization layer, and
• wherein the step of forming the sensor further includes forming of two interdigitated electrodes insulated from one another by the sensing material, the sensing material being configured and arranged to absorb moisture and to exhibit a dielectric constant that changes based upon moisture absorbed by the sensing material, the sensor being configured and arranged to detect the absorbed moisture by sensing capacitance between the two interdigitated electrodes and via the sensing material.

An integrated circuit comprising:

• a substrate carrying a plurality of circuit elements;
• a metallization stack interconnecting the circuit elements, the metallization stack including a patterned upper metallization layer having a first metal portion;
• a passivation stack covering the metallization stack, the passivation stack including a moisture-impenetrable layer and being configured and arranged to mitigate moisture penetration to the metallization stack and ensure operation of the circuit elements;
• a sensor including a sensing material on the passivation stack, the sensing material being coupled to the first metal portion by a via extending through the passivation stack;
• and
• a bond pad on the upper metallization layer,
• wherein the passivation stack has an opening therein defined by sidewalls of material in the passivation stack and extending from an upper surface of the passivation stack to the bond pad, therein exposing the bond pad without exposing the upper metallization layer.

A method of manufacturing an integrated circuit, comprising:

• providing a substrate carrying a plurality of circuit elements;
• forming a metallization stack interconnecting the circuit elements, the metallization stack including a patterned upper metallization layer having a first metal portion;
• forming a passivation stack covering the metallization stack, the passivation stack being configured and arranged to mitigate moisture penetration to the metallization stack and ensure operation of the circuit elements;
• forming a trench in the passivation stack to expose the first metal portion;
• forming a via in the trench;
• and
• forming a sensor including a sensing material on the passivation stack over the via to couple the sensing material to the first metal portion,
• wherein the step of forming the passivation stack further includes forming a bond pad portion on the upper metallization layer, and
• wherein the step of forming the passivation stack further includes forming an opening in the passivation stack, the opening defined by sidewalls of material in the passivation stack and extending from an upper surface of the passivation stack to the bond pad, therein exposing the bond pad without exposing the upper metallization layer.