High sensitivity optoelectronic device for detecting chemical species and related manufacturing method

A device, comprising:

• a die of semiconductor material having a front surface;
• an array of detection devices, each of the detection devices including:
• a first Geiger mode avalanche photodiode including:
• a cathode region having a first type of conductivity in the body, which forms the front surface;
• and
• an anode region having a second type of conductivity in the body, which extends in the cathode region starting from the front surface;
• a dielectric region which extends on the front surface;
• a first electrode on the dielectric region and electrically coupled to the anode region;
• a second electrode on the dielectric region;
• and
• a sensitive region on and interposed between the first and second electrodes, the sensitive region having a resistance that depends upon a concentration of said chemical species.

A detection system comprising:

• a light source;
• a driving stage configured to control the light source with a timing signal including a plurality of electrical pulses so as to generate a plurality of optical pulses;
• a device configured to receive said optical pulses and generate a current signal including a plurality of corresponding current pulses, the device including:
• a die of semiconductor material having a front surface;
• an array of detection devices, each of the detection devices including:
• a first Geiger mode avalanche photodiode including:
• a cathode region having a first type of conductivity in the body, which forms the front surface;
• and
• an anode region having a second type of conductivity in the body, which extends in the cathode region starting from the front surface;
• a dielectric region which extends on the front surface;
• a first electrode on the dielectric region and electrically coupled to the anode region;
• a second electrode on the dielectric region;
• and
• a sensitive region on and interposed between the first and second electrodes, the sensitive region having a resistance that depends upon a concentration of said chemical species.

A method for manufacturing a device for detecting a chemical species, the method comprising:

• forming a Geiger mode avalanche photodiode in a body of semiconductor material delimited by a front surface, wherein forming the Geiger mode avalanche photodiode includes:
• forming a cathode region, having a first type of conductivity, in the body and extending from the front surface;
• and
• forming an anode region having a second type of conductivity, which extends in the cathode region starting from the front surface;
• forming a dielectric region on the front surface;
• forming a first electrode on the dielectric region, the first electrode being electrically coupled to the anode region;
• forming a second electrode on the dielectric region;
• and
• forming a sensitive region on an interposed between the first and second electrodes, the sensitive region having a resistance that depends upon a concentration of said chemical species.