Method for manufacturing lateral germanium detectors
View Patent ↗An improved method for manufacturing a lateral germanium detector is disclosed. A detector window is opened through an oxide layer to expose a doped single crystalline silicon layer situated on a substrate. Next, a single crystal germanium layer is grown within the detector window, and an amorphous germanium layer is grown on the oxide layer. The amorphous germanium layer is then polished to leave only a small portion around the single crystal germanium layer. A dielectric layer is deposited on the amorphous germanium layer and the single crystal germanium layer. Using resist masks and ion implants, multiple doped regions are formed on the single crystal germanium layer. After opening several oxide windows on the dielectric layer, a refractory metal layer is deposited on the doped regions to form multiple germanide layers.
1. A method for fabricating a lateral germanium detector, said method comprising:
opening a detector window through an oxide layer to expose a single crystalline silicon layer situated on a substrate;
growing a single crystal germanium layer within said detector window, and an amorphous germanium layer on said oxide layer;
polishing and removing said amorphous germanium layer until a portion of said amorphous germanium layer is located around said single crystal germanium layer;
depositing a dielectric layer on said amorphous germanium layer and said single crystal germanium layer;
forming a plurality of doped regions on said single crystal germanium layer;
opening a plurality of oxide windows on said dielectric layer; and
depositing a refractory metal layer on said plurality of doped regions to form a plurality of germanide layers.
2. The method of claim 1 , wherein said lateral germanium detector is in a P-i-N configuration.
3. The method of claim 1 , wherein said lateral germanium detector includes and a p+ doped germanium layer.
4. The method of claim 1 , wherein said germanium detector includes and an n+ doped germanium layer.
5. The method of claim 1 , wherein said dielectric (TEOS) layer is a tetraethyl orthosilicate layer.
6. The method of claim 1 , wherein said dielectric layer is a germanium oxy-nitride layer.
7. The method of claim 1 , wherein said dielectric layer is a silicon nitride layer.
8. The method of claim 1 , wherein said plurality of doped regions are confined within said detector window.
9. The method of claim 1 , wherein said refractory metal deposition is confined within said detector window.
10. The method of claim 1 , wherein said amorphous germanium layer is completely removed in region located around said single crystal germanium layer.