A method for fabricating a miniaturized implantable device: fabricating an electronic system by monolithically integrating the electronic system on a first face of a substrate, the electronic system being configured, during operation of the implantable device, to communicate with an external device over a wireless communication link and to extract power for the implantable device from the wireless communication link; fabricating a coil by monolithically integrating the coil on the first face of the substrate, the coil being configured to provide the wireless communication link; and fabricating a plurality of electrodes (110, 115, 120) of an electrochemical sensor by monolithically integrating the plurality of electrodes (110, 115, 120) on the first face of the substrate, the plurality of electrodes (110, 115, 120) being configured to provide electrical interface between the electrochemical sensor of the implantable device and the electronic system; wherein: the fabricating of the plurality of electrodes (110, 115, 120) further comprises fabricating the plurality of electrodes (110, 115, 120) on a first metal layer separate from metal layers used to fabricate the electronic system; and the fabricating of the electronic system comprises creating vias to connect the electronic system to the plurality of electrodes (110, 115, 120), wherein the vias are created using a metal material different from a metal material used in fabricating of the electronic system. fabricating an electronic system by monolithically integrating the electronic system on a first face of a substrate, the electronic system being configured, during operation of the implantable device, to communicate with an external device over a wireless communication link and to extract power for the implantable device from the wireless communication link; fabricating a coil by monolithically integrating the coil on the first face of the substrate, the coil being configured to provide the wireless communication link; and fabricating a plurality of electrodes (110, 115, 120) of an electrochemical sensor by monolithically integrating the plurality of electrodes (110, 115, 120) on the first face of the substrate, the plurality of electrodes (110, 115, 120) being configured to provide electrical interface between the electrochemical sensor of the implantable device and the electronic system; wherein: the fabricating of the plurality of electrodes (110, 115, 120) further comprises fabricating the plurality of electrodes (110, 115, 120) on a first metal layer separate from metal layers used to fabricate the electronic system; and the fabricating of the electronic system comprises creating vias to connect the electronic system to the plurality of electrodes (110, 115, 120), wherein the vias are created using a metal material different from a metal material used in fabricating of the electronic system. the fabricating of the plurality of electrodes (110, 115, 120) further comprises fabricating the plurality of electrodes (110, 115, 120) on a first metal layer separate from metal layers used to fabricate the electronic system; and the fabricating of the electronic system comprises creating vias to connect the electronic system to the plurality of electrodes (110, 115, 120), wherein the vias are created using a metal material different from a metal material used in fabricating of the electronic system.