Method for manufacturing epitaxial wafer

摘要

A method for manufacturing an epitaxial wafer includes: a step of pulling a single crystal from a boron-doped silicon melt in a chamber based on a Czochralski process; and a step of forming an epitaxial layer on a surface of a silicon wafer sliced from the single crystal. The single crystal is allowed to grow while passed through a temperature region of 800 to 600° C. in the chamber in 250 to 180 minutes during the pulling step. The grown single crystal has an oxygen concentration of 10×1017 to 12×1017 atoms/cm3 and a resistivity of 0.03 to 0.01 Ωcm. The silicon wafer is subjected to pre-annealing prior to the step of forming the epitaxial layer on the surface of the silicon wafer, for 10 minutes to 4 hours at a predetermined temperature within a temperature region of 650 to 900° C. in an inert gas atmosphere. The method is to fabricate an epitaxial wafer that has a diameter of 300 mm or more, and that attains a high IG effect, and involves few epitaxial defects.

主权项

1. A method for manufacturing an epitaxial wafer, comprising: pulling a silicon single crystal from a boron-doped silicon melt in a chamber based on a Czochralski process; and forming an epitaxial layer on a surface of a silicon wafer sliced from the silicon single crystal; wherein the silicon single crystal is allowed to grow while passed through a temperature region of 800 to 600° C. in the chamber in 250 minutes or less and 180 minutes or more without a cooling device during the pulling;
wherein the grown silicon single crystal has an oxygen concentration less than a range of 10×1017 to 12×1017 atoms/cm3 (ASTMF121-1979) and a resistivity of 0.03 to 0.01 Ωcm; and wherein the silicon wafer is subjected to pre-annealing prior to the forming of the epitaxial layer on the surface of the silicon wafer, for 10 minutes to 4 hours at a predetermined temperature within a temperature region of 650 to 900° C. in an inert gas atmosphere, and BMDs generated in the wafer except for the epitaxial layer are at a density of 1×104/cm2 to 5×106/cm2.