A laser scanning annealing method using a hexagonal beam spot

Abstract

The invention discloses a laser scanning annealing method adopting a hexagonal beam spot, belonging to the semiconductor manufacturing technology. The hexagonal beam spot is formed by four baffle mechanisms capable of moving independently, each two of baffle mechanisms are arranged in an opposite way in an optical path, and an upper baffle and a lower baffle move independently or synchronously; and a left baffle and a right baffle move independently or synchronously, the four baffles all adopt rectangular baffles, the opposite sides of the upper baffle and the lower baffle or the left baffle and the right baffle are respectively provided with a V-shaped opening to form vertex angles A of a hexagon, and the vertexes of the vertex angles A are arranged on a central line. During wafer scanning annealing through the hexagonal beam spot, two adjacent scanning lines are overlapped for compensation, the problems of excessive or insufficient scanning between lines in the traditional line-by-line scanning can be solved, and the difficulty in implementation and the cost of implementation of the whole system cannot be increased.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing, and particularly relates to a method for performing laser sweep annealing by using a hexagonal beam spot. Background technique [0002] In the development process of integrated circuit manufacturing technology, as the device size continues to shrink, how to form an ultra-shallow junction (Ultra-Shallow Junction) in the source and drain regions of transistors with excellent performance at technology nodes such as 45nm and 32nm, and even smaller sizes ), becoming a crucial technical challenge. In order to meet the requirements for ultra-shallow PN junction fabrication of 45nm and below-generation devices on 12″ wafers, the traditional light rapid thermal annealing (RTA) using strip or spherical lamps as light sources can no longer meet the requirements of ultra-shallow junctions. A large number of studies have shown that in nanoscale CMOS devices, ultra-shallow and low-resistiv...

AI Technical Summary

Problems solved by technology

Even if the precision of the mechanical control system of the wafer stage or laser beam scanning is not enough, for example, the overlapping area of ​​the two laser beams is only 90 microns, the resulting total deposited laser energy is only the maximum between different areas on the wafer. A difference of 5% is an acceptable process deviation compared to no control at all

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