Periodic arrays of nanoscale structures on wafer surfaces can be fabricated using micro- and nano-fabrication processes. By changing the morphology and arrangement of array structures, precise control of light can be achieved, enabling the functionality of various optical devices. The paper simulates the nanoscale array structures on the wafer surface using Finite-Difference Time-Domain (FDTD) method and conducts microscopic imaging. After wavelength optimization, it was found that for the single-layer SiO2 array structure on the wafer surface, with shorter illumination wavelengths and larger objective numerical apertures, the characteristic information of the SiO2 structure becomes more prominent in the microscopic imaging. However, for the multi-layer SiO2-Si3N4-SiO2 array structure on the wafer surface, the illumination source no longer follows the principle that shorter wavelengths and larger numerical apertures result in better imaging quality. Instead, the optimal imaging quality is achieved with illumination wavelengths in the range of 230nm-260nm and a numerical aperture of 0.55 for the objective lens. Therefore, in practical testing, appropriate illumination wavelengths and numerical apertures for the objective lens should be selected to achieve the best imaging quality.
Subsurface defects of optical components will reduce the coating quality, transmission characteristics, damage threshold and other characteristics of optical components, and seriously affect the service life of optical components. In order to quickly and non-destructively detect subsurface defects of optical components, this paper proposes a method for utilizing Through-Focus Scanning Optical Microscopy (TSOM) to detect subsurface defects of optical components. Based on the traditional scanning method of optical microscopy, a set of two-dimensional optical images is collected by scanning through the various focus positions (from above the focus to below the focus, within the focus and out of focus). These acquired images are stacked and arranged in the Z direction to generate TSOM images, and the target is located by obtaining the maximum grayscale value of the detected feature. This method can detect subsurface defects of optical glass with a size of 2μm and locate the depth of defects. Through experimental testing of package samples, it was found that defects of the same depth exhibit consistent grayscale variations. This characteristic enables the differentiation between defects located on the surface or subsurface of the 30nm thick structure.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.