Method for fabricating a porous semiconductor body region
A method may include producing at least one trench in a semiconductor body, starting from a surface of the semiconductor body, then producing at least one porous semiconductor body region in the semiconductor body starting from the at least one trench at least along a portion of the side walls of the trench, and then filling the trench with a semiconductor material of the semiconductor body.
1. Method for fabricating a porous semiconductor body region, comprising:
producing a plurality of trenches in a semiconductor body,
producing a plurality of porous semiconductor body regions in the semiconductor body, a first of the plurality of the porous semiconductor body regions associated with a first trench of the plurality of trenches and a second of the plurality of the porous semiconductor body regions associated with a second trench of the plurality of trenches, the first and second porous semiconductor body regions providing a cohesive porous semiconductor body region,
filling the plurality of trenches with a semiconductor material.
2. Method according to claim 1 , in which the plurality of porous semiconductor body regions are produced by means of anodic oxidation of the semiconductor body in the plurality of trenches.
3. Method according to claim 1 , in which the ratio L/B of length to width of at least one of the plurality of porous semiconductor body regions is greater than 3.
4. Method according to claim 1 , in which at least one of the plurality of trenches is filled epitaxially.
5. Method according to claim 1 , in which the plurality of trenches is filled with a semiconductor material of the semiconductor body.
6. Method for introducing a foreign substance into a semiconductor body, comprising:
producing a plurality of porous semiconductor body regions in the semiconductor body, a first of the plurality of the porous semiconductor body regions associated with a first trench and a second of the plurality of the porous semiconductor body regions associated with a second trench, the first and second porous semiconductor body regions providing a cohesive porous semiconductor body region,
providing a foreign substance in at least a portion of the cohesive porous semiconductor body region,
heatinq the semiconductor body with the cohesive porous semiconductor body region produced therein, wherein the foreign substance diffuses along at least a portion of the cohesive porous semiconductor body region.
7. Method according to claim 6 , in which the cohesive porous semiconductor body region is produced such that the cohesive porous semiconductor body region extends from a surface of the semiconductor body into the semiconductor body.
8. Method according to claim 6 , in which the foreign substance is provided at the surface of the semiconductor body.
9. Method according to claim 8 , in which the foreign substance is provided as a solid layer at the surface of the semiconductor body.
10. Method according to claim 8 , in which the foreign substance is provided in gaseous form at the surface of the semiconductor body.
11. Method according to claim 6 , in which the foreign substance is implanted into the cohesive porous semiconductor body region.
12. Method according to claim 6 , in which the foreign substance provided is oxygen.
13. Method according to claim 6 , in which the foreign substance provided is a dopant for the semiconductor body.
14. Method according to claim 6 , in which the foreign substance diffuses from the cohesive porous semiconductor body region into the adjoining semiconductor body.
15. Method according to claim 6 , in which the semiconductor body with the cohesive porous semiconductor body region produced therein is heated at least to a temperature in the range from 800° C. to 1200° C.