Enhanced visible near-infrared photodiode and non-invasive physiological sensor

A non-invasive physiological sensor which measures physiological parameters of a monitored patient, the sensor comprising:

• an input configured to receive a drive signal from a driver circuit;
• an emitter electrically coupled to the input and configured to emit optical radiation at one or more wavelengths responsive to the drive signal;
• one or more detectors configured to be positioned proximate to the emitter and tissue of a patient by a sensor housing, the one or more detectors comprising one photodiode that is part of an integrated semiconductor structure, the one photodiode being configured to detect the optical radiation after attenuation by the tissue of the patient and generate a detector signal responsive to the detected optical radiation;
• and
• an output electrically coupled to the one or more detectors and configured to output the detector signal,
• wherein the one photodiode is configured to generate the detector signal with a signal strength sufficient for the detector signal to be usable to determine measurement values for one or more physiological parameters of the patient from the detected optical radiation at the wavelengths ranging from 450 nm to 1400 nm,
• the one photodiode comprising a window layer, a diffusion region, an absorption region, and a semiconductor wafer, the absorption region being between the window layer and the semiconductor wafer, and
• the window layer and the diffusion region are p-type regions, the window layer having a thickness ranging from about 25 nm to about 150 nm, the absorption region being an undoped region, the semiconductor wafer being a n-type region.