Silicon Iodide CVD for Nitride-Selective Amorphous Silicon Films
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for depositing amorphous silicon films require complex patterning and etch processes, which are time-consuming and costly, especially as device feature sizes decrease, and there is a need for precise selective deposition on metallic nitride versus metallic oxide surfaces.
Innovation Solution
A method involving a silicon iodide precursor in a controlled environment, such as a chemical vapor deposition chamber, heats the substrate to a specific temperature to selectively deposit amorphous silicon on metallic nitride surfaces relative to metallic oxide surfaces, using a silicon iodide precursor without plasma excitation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If blanket deposition and photolithography patterning are used to deposit amorphous silicon film, then the amorphous silicon film can be deposited on the substrate, but the process becomes complex and time-consuming
Solution Approach 1:
The invention applies local quality by creating different surface properties in different regions of the substrate. Specifically, metallic nitride regions are treated to be hydrophilic while metallic oxide regions remain hydrophobic, enabling selective deposition of amorphous silicon only on the hydrophilic nitride regions through vapor-phase precursor exposure
Solution Approach 2:
The invention changes the surface energy parameters of different substrate regions through plasma treatment. By selectively exposing metallic nitride regions to oxygen plasma, the surface chemistry is modified to create hydrophilic regions with higher surface energy, which then selectively attract and deposit the amorphous silicon precursor vapor
2Manufacturing precision
If photolithography and etch processes are used to pattern amorphous silicon film, then the desired pattern can be achieved, but the process becomes expensive and time-consuming
Solution Approach 1:
The invention performs preliminary action by pre-treating the substrate surface with plasma to create hydrophilic metallic nitride regions before deposition. This preliminary surface modification enables subsequent selective deposition without requiring post-deposition patterning steps, thereby eliminating time-consuming photolithography and etching processes
Solution Approach 2:
The invention extracts and eliminates the photolithography and etching steps from the traditional deposition-patterning process sequence. By implementing selective deposition through surface energy differentiation, the method removes the need for separate patterning operations, directly achieving patterned amorphous silicon films
3Device complexity
If selective deposition is used to deposit amorphous silicon on metallic nitride surfaces, then the need for patterning steps is eliminated, but achieving high selectivity requires precise control of deposition conditions
Solution Approach 1:
The invention controls deposition selectivity by precisely adjusting the surface energy parameters through plasma treatment duration and power, precursor vapor pressure, and substrate temperature. These parameter controls ensure that only hydrophilic metallic nitride regions deposit amorphous silicon while hydrophobic oxide regions remain unaffected, achieving selectivity exceeding 80%
Solution Approach 2:
The invention replaces mechanical patterning methods (photolithography masks and etching) with a chemical/physical field-based selective deposition process. By using vapor-phase precursors and plasma treatment to create surface energy differences, the method achieves patterning through field-induced selective reactions rather than mechanical removal
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
Achieves high selectivity and precision in depositing amorphous silicon films, reducing complexity and cost by eliminating the need for subsequent patterning steps, with selectivity exceeding 80% and achieving uniform film thickness even in high aspect ratio features.
Implementation Method 1
heating the substrate to a deposition temperature; selectively depositing the amorphous silicon film on the metallic nitride surface relative to the metallic oxide surface
Implementation Method 2
contacting the substrate with silicon iodide precursor; selectively depositing the amorphous silicon film
Data Source
AI summary
A method for selectively depositing an amorphous silicon film on a substrate comprising a metallic nitride surface and a metallic oxide surface is disclosed. The method may include; providing a substrate within a reaction chamber, heating the substrate to a deposition temperature, contacting the substrate with silicon iodide precursor, and selectively depositing the amorphous silicon film on the metallic nitride surface relative to the metallic oxide surface. Semiconductor device structures including an amorphous silicon film deposited by selective deposition methods are also disclosed.