Metal-semiconductor-metal photodetectors

A metal-semiconductor-metal photodetector configured to detect incident light in a given range of wavelengths comprising:

• an absorbing semiconductor layer configured to absorb light within said given range of wavelengths;
• a first semiconductor layer made of a first semiconductor material having a first bandgap and in electrical contact with said absorbing semiconductor layer;
• a first metal electrode configured to be electrically connected to a negative pole of a voltage generator;
• wherein
• the first metal electrode is in electrical contact with the first semiconductor layer;
• the first semiconductor layer is arranged between said first metal electrode and the absorbing semiconductor layer;
• and
• the first metal electrode and the first semiconductor layer are configured to produce an electron Schottky junction under application of a bias voltage, wherein the electron Schottky junction has an electron Schottky barrier seen by the electrons greater than half the first bandgap of the first semiconductor material;
• a second semiconductor layer made of a second semiconductor material different from the first semiconductor material and having a second bandgap, wherein the second semiconductor layer is in electrical contact with said absorbing semiconductor layer;
• a second metal electrode configured to be electrically connected to a positive pole of said voltage generator;
• wherein
• the second metal electrode is in electrical contact with the second semiconductor layer;
• the second semiconductor layer is arranged between said second metal electrode and the absorbing semiconductor layer;
• and
• the second metal electrode and the second semiconductor layer are configured to produce a hole Schottky junction under application of a bias voltage, wherein the hole Schottky junction has a hole Schottky barrier seen by the holes greater than half the second bandgap of the second semiconductor material.