Biomolecular image sensor and method thereof for detecting biomolecule

A biomolecule image sensor, comprising:

• an image sensing element, comprising a plurality of unit pixels disposed in an array on a substrate, wherein each of the plurality of unit pixels comprises at least one photoelectric conversion element, the photoelectric conversion element configured to receive an incident light to generate electrons, and a surface of the image sensing element configured to receive the incident light, wherein the surface of the image sensing element is defined as a light receiving surface;
• a passivation layer, disposed on the light receiving surface;
• a bonding layer, disposed on the passivation layer, disposed to be a plurality of island structures in an array, and each of the plurality of island structures corresponding to each of the plurality of unit pixels;
• a plurality of light blocking layers, disposed on the passivation layer and corresponding to spaces between each of the plurality of unit pixels;
• a plurality of detection molecules, disposed on the bonding layer, and configured to contact a sample to the detection molecules to bind a biomolecule in the sample;
• and at least one readout circuit, coupled to each of the plurality of unit pixels, and configured to generate a voltage signal based on a number of electrons;
• wherein a height of each of the plurality of island structures is greater than a height of the plurality of light blocking layers, a top portion of each of the plurality of island structures extends to a top portion of each of the plurality of light blocking layers, the plurality of island structures are separated from each other, and a surface area of the top portion of each of the plurality of island structures equals to a surface area of each of the plurality of unit pixels;
• wherein each of the plurality of unit pixels is configured to detect the incident light, the incident light comprises a light emitted by a fluorescent marker or a chemiluminescent marker on the biomolecule, the incident light detected by each of the plurality of unit pixels configured to generate electrons by the photoelectric conversion element, the readout circuit configured to generate a voltage signal based on the number of the electrons and analyze a presence or a concentration of the biomolecule based on the voltage signal;
• wherein when the biomolecule image sensor is configured to be used to detect the presence and/or concentration of the biomolecule, a quantification is configured to be performed by an analog colorimetric method or by a digital method;
• wherein the analog colorimetric method is defined as follows:
• the incident light received by the unit pixels is one single readout configured to determine the presence of the biomolecule or further compare with a standard curve in order to obtain the concentration of the biomolecule;
• and
• wherein the digital method is defined as follows:
• according to a predetermined threshold, the unit pixels with the signal readout exceeding the predetermined threshold are defined as 1 and the unit pixels with the signal readout not exceeding the predetermined threshold are defined as 0, and the number of unit pixels defined as 1 is configured to be calculated and compared with the standard curve in order to obtain the concentration of the biomolecule more accurately.