Method of manufacturing semiconductor devices by using epitaxy and semiconductor devices with a lateral structure
Epitaxy troughs are formed in a semiconductor substrate, wherein a matrix section of the semiconductor substrate laterally separates the epitaxy troughs and comprises a first semiconductor material. Crystalline epitaxy regions of a second semiconductor material are formed in the epitaxy troughs, wherein the second semiconductor material differs from the first semiconductor material in at least one of porosity, impurity content or defect density. From the epitaxy regions at least main body portions of semiconductor bodies of the semiconductor devices are formed.
1. A method of manufacturing semiconductor devices, the method comprising:
forming epitaxy troughs in a semiconductor substrate, wherein a matrix section of the semiconductor substrate laterally separates the epitaxy troughs and comprises a first semiconductor material;
forming crystalline epitaxy regions of a second semiconductor material in the epitaxy troughs, wherein the second semiconductor material differs from the first semiconductor material in at least one of porosity, impurity content or defect density; and
forming, from the epitaxy regions, at least main body portions of semiconductor bodies of the semiconductor devices.
2. The method of claim 1 , wherein the first and second semiconductor materials have a same main constituent or same main constituents.
3. The method of claim 2 , wherein the same main constituent is silicon or the same main constituents is silicon carbide.
4. The method of claim 1 , wherein
forming at least the main body portions comprises forming, in each main body portion, an anode/body well forming a first pn junction with a main structure in the semiconductor body.
5. The method of claim 1 , wherein forming at least the main body portions comprises forming, in each main body portion, a plurality of transistor cells electrically arranged in series.
6. The method of claim 1 , further comprising diffusing impurities from the matrix section into the epitaxy regions.
7. The method of claim 6 , wherein the impurities comprise non-doping impurities.
8. The method of claim 6 , wherein the impurities comprise oxygen atoms.
9. The method of claim 6 , wherein the impurities comprise dopants.
10. The method of claim 1 , wherein a conductivity type of the epitaxy region is complementary to a conductivity type of the matrix section.
11. The method of claim 1 , further comprising pretreating at least rip sidewall sections of the matrix section to form the first semiconductor material.
12. The method of claim 1 , further comprising forming, after forming the epitaxy troughs, a horizontal porous layer in the semiconductor substrate.
13. The method of claim 1 , further comprising increasing, by at least 10%, porosity in at least rip sidewall sections of the matrix section to form the first semiconductor material.
14. The method of claim 13 , further comprising separating the semiconductor bodies from the semiconductor substrate by removing at least the porous rip sidewall sections of the matrix section.
15. The method of claim 1 , further comprising separating the semiconductor bodies from the semiconductor substrate along dicing streets running in ribs of the matrix section.
16. The method of claim 1 , wherein the semiconductor bodies comprise lateral body portions formed from the first semiconductor material, wherein the lateral body portions surround the main body portions.
17. The method of claim 1 , wherein the semiconductor bodies comprise base portions from the semiconductor substrate.
18. The method of claim 1 , wherein the semiconductor bodies are formed from the epitaxy regions.