SiOCH Thin Film Deposition Using Single Precursor and UV Annealing
Solution Overview
Problem
Existing processes for producing porous SiOCH layers are complex and energy-intensive, requiring multiple precursors and high thermal budgets, which complicates their application in microelectronics and gas sensors.
Innovation Solution
A simplified process using chemical vapor deposition from a single precursor at low temperatures (≤250°C) followed by UV-assisted heat treatment to achieve porosity levels comparable to multi-precursor methods, reducing energy consumption and thermal budget.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If multiple precursors including a porogen are used in PECVD deposition, then porosity can be achieved in the SiOCH layer, but the process complexity increases
Solution Approach 1:
The invention extracts the porogen function from the deposition step by using a single precursor that already contains the necessary organic groups for porosity. The porosity is achieved through the decomposition of methyl groups during annealing, eliminating the need to introduce and remove separate porogen materials, thus simplifying the overall process while maintaining porosity
Solution Approach 2:
The invention changes the chemical composition parameters of the precursor to include sufficient carbon and hydrogen content (from methyl groups) that will decompose during annealing to create porosity. By adjusting the precursor formula and deposition conditions, the process achieves porosity through thermal decomposition rather than porogen removal
2Strength
If UV-assisted heat treatment at 400°C is applied to improve mechanical strength and lower dielectric constant, then film properties are enhanced, but energy consumption increases
Solution Approach 1:
The invention changes the temperature parameter from 400°C to a lower range (200-350°C) by modifying the precursor composition and deposition conditions. The reduced thermal budget is compensated by optimizing the carbon content and molecular structure of the precursor, allowing porosity and film properties to be achieved at lower energies
Solution Approach 2:
The invention uses labile methyl groups in the precursor that decompose during annealing to create porosity and improve film properties. These temporary organic groups serve their purpose during processing and are removed, leaving the desired porous structure without requiring high-energy UV-assisted treatment at 400°C
3Manufacturing precision
If deposition temperature is increased to 300-350°C for PECVD, then film quality improves, but thermal budget increases
Solution Approach 1:
The invention changes the deposition temperature parameter to a lower range (150-250°C) by using precursors with optimized chemical composition. The lower temperature is compensated by adjusting the precursor reactivity and plasma conditions, achieving good film quality with reduced thermal budget suitable for temperature-sensitive substrates
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The process achieves porosity levels of at least 4% in SiOCH layers, enhancing their suitability for microelectronics and gas sensors while simplifying the production process and reducing energy usage.
Implementation Method 1
deposition of the SiOCH layer by chemical vapor deposition from a single precursor at a temperature between 100°C and 250°C
Implementation Method 2
annealed, advantageously assisted by UV radiation
Implementation Method 3
heat treatment of said thin layer at a temperature between 350°C and 500°C
Data Source
Figure 1A~2
Figure 3~4
AI summary
A process for producing a SiOCH thin film comprising the steps: - deposition of a SiOCH thin film by chemical vapor deposition from a single precursor at a temperature between 100°C and 250°C, - heat treatment of said thin film at a temperature between 350°C and 500°C assisted.