Semiconductor Film Flatness via Photosensitive Barrier
Solution Overview
Problem
In semiconductor device manufacturing, materials with high flowability tend to flow from densely arranged level difference regions into sparsely arranged or bare regions, resulting in uneven film surfaces, making it difficult to achieve uniform film heights during processing.
Innovation Solution
A method involving the formation of a photosensitive film around the periphery of densely arranged level difference regions, followed by an applied film with flowability to cover both regions, which suppresses the flow of the applied film into the sparsely arranged or bare regions, allowing for a uniform film height through etch-back treatment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If an applied film having flowability is formed to cover the first region and second region, then the projections and recesses formed due to level difference portions are buried, but the applied film flows from the first region into the second region resulting in uneven film surface
Solution Approach 1:
A photosensitive film is formed in advance on the second region before forming the applied film. This preliminary action creates a physical barrier that prevents the applied film from flowing into the second region, thereby maintaining uniform film height in the first region while still allowing the applied film to bury projections and recesses.
Solution Approach 2:
The photosensitive film acts as an intermediary barrier between the first region and second region. It restricts the flow of the applied film having flowability, preventing it from moving from the first region into the second region, thus solving the problem of uneven film surface while maintaining the beneficial flow properties where needed.
2Manufacturing precision
If a dummy electrode and polysilicon film are formed with gap groove to suppress anti-reflection film disappearance, then film flowability is controlled, but device structure becomes more complex
Solution Approach 1:
The invention extracts and removes the complex dummy electrode and gap groove structures from the device design. Instead, it uses a simpler photosensitive film pattern formed only on the second region to achieve the same goal of controlling film flow and preventing disappearance, thereby reducing device structural complexity.
Solution Approach 2:
The photosensitive film serves as a temporary, disposable structure used only during the film formation process. After the applied film is successfully formed with uniform height, the photosensitive film can be removed, leaving no permanent structural complexity in the final device.
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
This approach enables the attainment of a semiconductor device with a uniform film height in densely arranged regions while preventing the applied film from flowing into adjacent regions, improving flatness and reducing manufacturing costs by eliminating the need for additional structural elements to prevent outflow.
Implementation Method 1
an applied film having flowability is formed to cover the first region and the photosensitive film
Implementation Method 2
A photosensitive film is formed at least on a portion of the second region to surround a periphery of the first region as seen in plan view
Implementation Method 3
processing such as etch-back treatment is performed on a film to be treated on the first region
Data Source
AI summary
Provided is a method for manufacturing a semiconductor device including a film to be treated having a high flatness. A semiconductor substrate having a surface and including a first region and a second region on the surface is prepared, the first region being a region in which a plurality of first level difference portions are formed, the second region being a region in which a plurality of second level difference portions arranged more sparsely than the plurality of first level difference portions are formed, or a region in which no level difference portion is formed. A photosensitive film is formed on a portion of the second region to surround a periphery of the first region as seen in plan view. An applied film having flowability is formed to cover the first region and the photosensitive film. A portion of the applied film at least on the first region is removed.