Device for gas-sensoring electrodes

A sensing element, comprising:

• a support plate;
• at least two three-dimensional arrangements of electrodes applied on the support plate, the arrangements of electrodes forming trenches of a depth of between 10 μm and 100 μm;
• a gas-sensitive layer arranged to a predetermined height only in the trenches, the arrangements of electrodes measuring changes in at least one of potential, capacitance and conductivity in the gas sensitive layer, the predetermined height of the gas-sensitive layer being less than the depth of the trenches;
• and
• a catalytically active layer covering the gas sensitive layer.

An electrochemical sensor for determining a gas concentration, comprising:

• at least one of a sensing element and sensor array, the at least one sensing element and sensor array, including
• a support plate,
• at least one three-dimensional arrangement of electrodes applied on the support plate, the arrangement of electrodes forming trenches of a depth of between 10 μm and 100 μm,
• a gas-sensitive layer arranged to a predetermined height only in the trenches, the arrangement of electrodes measuring changes in at least one of potential, capacitance and conductivity in the gas sensitive layer, the predetermined height of the gas-sensitive layer being less than the depth of the trenches, and
• a catalytically active layer covering the gas sensitive layer.

A method for manufacturing a sensing element having a three-dimensional electrode arrangement, comprising the steps of:

• depositing an electroplating starter layer onto a support plate;
• applying a photoresist at a thickness of between 10 μm to 100 μm onto the electroplating starter layer;
• patterning the photoresist to form resist trenches;
• filling the resist trenches by electroplating up to a defined height;
• removing the photoresist to form electrode trenches;
• etching away the electroplating starter layer from within the electrode trenches;
• placing a gas sensitive material into the electrode trenches up to a predetermined height that is less than the depth of the electrode trenches;
• and applying a catalytically active material onto the gas sensitive material in the electrode trenches.