Novel Deposition Technique for Fabricating Films with Customized Thickness Profiles

Area of Science:

• Materials Science
• Thin Film Deposition
• Nanotechnology

Background:

• Precise control over thin film thickness is crucial for advanced optical and electronic devices.
• Existing deposition techniques often lack the flexibility to create arbitrary thickness profiles efficiently.

Purpose of the Study:

• To develop a novel deposition technique for fabricating thin films with arbitrary thickness profiles.
• To demonstrate the capability of the method for creating linear and sinusoidal thickness variations.
• To design and fabricate a linear variable filter using this technique.

Main Methods:

• Utilized a fixed shadow mask with a custom-designed opening curve.
• Employed a rotating sample carrier plate positioned coaxially with the shadow mask.
• Fabricated thin films with linear gradients (49.3 and 86.8 Å/mm) and sinusoidal profiles (40 mm period).
• Designed a linear variable filter using a quarter-wavelength stack (Si3N4/SiO2) and a TiO2 cavity layer with varying thickness.

Main Results:

• Successfully deposited thin films with designed linear and sinusoidal thickness profiles in a single step.
• Demonstrated the fabrication of a linear variable filter with a linearly varying thickness profile.
• Achieved consistent thickness profiles across multiple samples positioned at different circumferential locations on the carrier plate.

Conclusions:

• The novel deposition technique offers precise control over arbitrary thin film thickness profiles.
• The method is efficient, requiring no complex internal chamber devices and is suitable for mass production.
• This technique opens possibilities for advanced optical components and tailored material properties.