A Chemical Mechanical Polishing Head with Controllable Spacing

Abstract

The invention discloses a chemical-mechanical grinding head with controllable spacing. The bottom of the grinding support seat is raised and lowered to be provided with an annular grinding retaining ring; The inner diameter of the retaining ring is larger than the diameter of the wafer; the limiting bottom ring is set coaxially with the grinding and retaining ring; the limiting bottom ring is located on the lower side of the grinding and retaining ring and the gap between the two is adjustable; the inner diameter of the limiting bottom ring It is larger than the diameter of the grinding pad; the upper end surface of the grinding platform is formed with a coaxial limit ring groove for inserting the limit bottom ring; a limit device for limiting the limit bottom ring is arranged in the limit ring groove; The bottom ring is arranged to rotate relative to the grinding platform. When the present invention works, the gap between the grinding retaining ring and the grinding pad is kept at a certain distance, so that the limit bottom ring will not be worn by the grinding pad, and at the same time, it is beneficial to the discharge of grinding liquid and grinding products, and the grinding quality is improved.

Description

technical field [0001] The invention relates to the technical field of chemical mechanical polishing, in particular to a chemical mechanical polishing head with controllable spacing. Background technique [0002] In the manufacturing process of semiconductor devices, it is often necessary to use a grinding process to grind the wafer and the materials formed on the wafer, so as to remove unnecessary materials and obtain a flat surface. One commonly used grinding process is chemical mechanical grinding. [0003] In the existing chemical mechanical polishing equipment, the grinding pad on the grinding platform is set to rotate together with the grinding platform. After the wafer is absorbed by the grinding head, it contacts the grinding pad and is pressurized to rotate and move on the grinding pad. Perform mechanical polishing, and supply polishing liquid to the polishing pad through the polishing liquid supply unit, so as to realize mechanical polishing and chemical polishing...

AI Technical Summary

Problems solved by technology

However, during the grinding process, the bottom surface of the grinding and retaining ring attached to the grinding pad will also be worn, which will make the groove on the grinding and retaining ring shallower, resulting in poor discharge, and the accumulation of grinding by-products and excess grinding fluid In the grinding and holding ring, defects such as wafer scratches will be caused, and the grinding rate will also be reduced, thereby reducing the grinding efficiency

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