Abstract: A method includes forming a tier stack of an electronic circuit including a plurality of tiers. A tier includes a first layer of a first dielectric material and a second layer of a second dielectric material. The method further includes forming a first pillar, a second pillar, and a third pillar each extending through at least a portion of the plurality of tiers. The first pillar is disposed between the second pillar and the third pillar. The method further includes selectively etching the second layer of the second dielectric material of each of the plurality of tiers to form a void within each of the plurality of tiers. The method further includes filling the void within each of the plurality of tiers with metal to form a plurality of conductive lines.

Abstract: Described herein are ways of providing a hearing aid wearer visual indications as to the operating status of the hearing aid. Multi-colored LEDs (light emitting diodes) are operated by the hearing aid's processing circuitry to convey light to an indicator light on the hearing aid enclosure using different colors to indicate different operating statuses. The LEDs may also be used to provide information regarding changes made to operating parameters.