Method for manufacturing a microbolometer with thermistor material made from vanadium oxide having improved performances

A process for fabricating at least one microbolometer, comprising the following steps:

• producing anchoring pillars that extend from a substrate, and that each comprise an electrical conductor;
• producing thermally insulating arms that each comprise a layer of a metal making contact with the electrical conductor of the anchoring pillar and forming a biasing electrode;
• producing a membrane that is intended to be suspended above the substrate by the anchoring pillars and the thermally insulating arms, and that contains:
• said biasing electrodes,
• an intermediate insulating layer, which partially covers the biasing electrodes and contains apertures that open onto the biasing electrodes,
• a thermistor material, which is made of a first compound based on vanadium oxide and which is continuously formed from a central segment which covers the intermediate insulating layer, and from lateral segments which make contact with the biasing electrodes through the apertures;
• determining a non-zero effective amount of at least one additional chemical element that, when incorporated by ion implantation into the first compound, forms a modified compound, the electrical resistivity ρL of which at room temperature is lower than or equal to 10% of the electrical resistivity ρc at room temperature of said first compound;
• incorporating locally, by ion implantation, into the lateral segments of the thermistor material, an amount of said additional chemical element higher than or equal to the effective amount.