Dome-Shaped Semiconductor Profiles for Leakage Current Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lithographically patterned devices face issues with leakage current and non-uniform deposition due to sharp edges and abrupt transitions in semiconductor features, leading to structural discontinuities and inefficient oxide growth, especially on non-absorbing substrates where ink tends to spread and form undesirable 'coffee ring' profiles.
Innovation Solution
The development of printed semiconductor, insulator, and conductor features with smooth and/or dome-shaped geometries, achieved through precise control of ink composition and printing processes, such as inkjet printing, to prevent sharp transitions and ensure uniform deposition and oxidation, thereby enhancing device reliability and reducing leakage current.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional lithographically patterned devices with sharp edges and abrupt transitions are used, then manufacturing precision is achieved, but leakage current increases and device reliability deteriorates
Solution Approach 1:
The patent applies curvature by forming semiconductor features with smooth, rounded edges and dome-shaped cross-sectional profiles instead of sharp edges and abrupt transitions. This is achieved through controlled deposition processes that create continuously varying thickness profiles, eliminating the geometric discontinuities that cause leakage current at cross-over locations between gate electrodes and active features.
2Manufacturing precision
If conventional lithographically defined features with sharp edges are used, then manufacturing precision is achieved, but oxide growth uniformity deteriorates
Solution Approach 1:
The patent uses curved, dome-shaped feature profiles to provide continuously varying surface angles that facilitate uniform oxide growth. The smooth transitions eliminate sharp edges where oxide thickness would be non-uniform, allowing thermal oxidation to proceed evenly across the entire feature surface while maintaining precise dimensional control through the deposition process parameters.
3Ease of manufacture
If ink is printed on non-absorbing substrates, then ease of manufacture is improved, but ink spreading occurs forming coffee ring profiles
Solution Approach 1:
The patent controls the physical and chemical parameters of the ink composition, including solvent evaporation rate, viscosity, and surface tension, to prevent coffee ring formation. By adjusting these parameters, the ink maintains uniform distribution during deposition and drying on non-absorbing substrates, forming the desired smooth, dome-shaped profiles without edge concentration effects.
4Reliability
If smooth and dome-shaped semiconductor features are formed, then leakage current is reduced and reliability is improved, but manufacturing complexity increases
Solution Approach 1:
The patent combines pattern formation and profile control into a single deposition step. By using printing or deposition techniques that directly form features with smooth, dome-shaped profiles, the process eliminates the need for separate steps to create sharp edges followed by additional processing to round them, thereby reducing overall manufacturing complexity while achieving the desired geometric characteristics.
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 results in improved device reliability, reduced leakage current, and more uniform thermal oxidation, leading to enhanced performance and longer lifespan of electronic devices like transistors, diodes, and capacitors by preventing structural discontinuities and promoting complete step coverage.
Implementation Method 1
achieved through precise control of ink composition and printing processes, such as inkjet printing
Implementation Method 2
the evaporation rate of the deposited ink is greatest near its edge, and liquid from the bulk of the deposited ink tends to flow to the edge as evaporation occurs
Implementation Method 3
more uniform thermal oxidation
Data Source
AI summary
The present invention relates to electrically active devices (e.g., capacitors, transistors, diodes, floating gate memory cells, etc.) having dielectric, conductor, and/or semiconductor layers with smooth and/or dome-shaped profiles and methods of forming such devices by depositing or printing (e.g., inkjet printing) an ink composition that includes a semiconductor, metal, or dielectric precursor. The smooth and/or dome-shaped cross-sectional profile allows for smooth topological transitions without sharp steps, preventing feature discontinuities during deposition and allowing for more complete step coverage of subsequently deposited structures. The inventive profile allows for both the uniform growth of oxide layers by thermal oxidation, and substantially uniform etching rates of the structures. Such oxide layers may have a uniform thickness and provide substantially complete coverage of the underlying electrically active feature. Uniform etching allows for an efficient method of reducing a critical dimension of an electrically active structure by simple isotropic etch.