Optical sensor for thin film detection

Abstract

This invention discloses an optical sensor composed of pump diode lasers, a chopper and a beam splitter prism, in which, the first pump diode laser and the second pump diode laser output two beams of laser of different frequencies and output a beam laser by regulation of the chopper to irradiate on a dual grid splitter to form a 2-D beam array to be reflected on a CCD focal plane and imaged by a film sample to display the light spot position distribution information and the light intensity variety information of each spot of the reflection beam array to get the growing rate of the film by computing the transformation information of said light intensity, evaluate the film stress by beam offset information and Stoney equation and evaluate components of the material based on the incident light vacuum wavelength lambda< 0 > put forward by Brunner and function of the Al component x.

Description

technical field [0001] The invention belongs to the field of optical technology and relates to film detection, in particular to an optical sensor for detecting film growth rate and stress. Background technique [0002] It is well known in the industry that because stress changes in the film manufacturing process may cause the internal connection failure and delamination of the film to degrade the product quality, it is of great significance to control the degree of deformation of the film during the manufacturing process. Modern semiconductor processing requires electronic and optoelectronic equipment to precisely control the deposition process of thin film materials. At present, most processing processes need to measure parameters such as gas flow rate, deposition chamber pressure, and growth environment temperature in order to control the deposition process of thin film materials. . These parameters are generally preset empirical parameters for growing a film with a certa...

AI Technical Summary

Problems solved by technology

There are two shortcomings in this on-site film stress detection system: one is that the two laser beams must be strictly focused, which requires too high requirements for the design, installation, daily debugging and maintenance of the optical system; the other is that due to the inertia of the PSD, when the sample rotates at a high speed , can only detect the average value of the stress of the whole film, but can't do anything to detect the stress and growth rate of the local area of ​​the film

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