Edge-trimmed composite back sealing layer structure used for silicon wafer, and manufacturing method thereof

Abstract

The invention discloses an edge-trimmed composite back sealing layer structure used for a silicon wafer. The edge-trimmed composite back sealing layer structure comprises a polysilicon back sealing layer and a silicon dioxide back sealing layer, wherein the polysilicon back sealing layer covers the back surface, back surface bevel edge regions and fringe regions of the silicon wafer; the silicon dioxide back sealing layer covers the polysilicon back sealing layer and is positioned on the back surface of the silicon wafer. According to the edge-trimmed composite back sealing layer structure used for the silicon wafer, only monocrystal silicon serving as a body material is left on the front surface bevel edge of the silicon wafer, and the front surface bevel edge has a smooth surface with high quality, which makes almost no difference from a polished surface. Only the monocrystal silicon layers are grown on the front surface bevel edge of the silicon wafer and the polished surface in epitaxial processing, seamless connection can be achieved, the layered phenomenon cannot occur, and the problems of particle contaminant, edge stacking fault and pyramid in epitaxial processing can be solved, thereby increasing the yield in manufacturing process.

Description

technical field [0001] The invention relates to the fields of semiconductor and material production and application, in particular to a compound back-sealing layer structure with edge removal for silicon wafers and a manufacturing method thereof. Background technique [0002] The back seal design of the silicon wafer has an important impact on the subsequent epitaxial process. Improper back seal design will cause problems such as self-doping and abnormal growth of silicon slag on the back, resulting in the loss of the yield of the epitaxial process. figure 1 and figure 2 Shown is a common back-sealing design for silicon wafers with edge removal treatment, which adopts the composite back-sealing layer design of inner polysilicon back-sealing + outer silicon dioxide back-sealing. Among them, the polysilicon back-sealing layer plays the role of external gettering, and the silicon dioxide back-sealing layer plays the role of back-sealing. [0003] However, since the silicon w...

AI Technical Summary

Problems solved by technology

[0004] The object of the present invention is to provide a composite back-sealing layer structure with edge removal for silicon wafers and its manufacturing method that solves the problems of particle contamination, edge stacking faults, and pyramids caused by delamination.

Images