Fin Structure IPA Rinse and Bake to Prevent Collapse
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current FinFET fabrication methods face issues with current leakage due to the design of fin-shaped structures, leading to performance degradation, particularly as pitch sizes reduce and fin-shaped structures become more susceptible to falling during cleaning processes.
Innovation Solution
A method involving the use of isopropyl alcohol (IPA) for rinsing and a controlled baking process to dry fin-shaped structures, followed by forming a gate oxide layer, which prevents structural failure by maintaining structural integrity during pitch reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If pitch size is reduced to scale down FinFET devices, then device integration density is improved, but fin-shaped structures become more susceptible to falling during cleaning processes
Solution Approach 1:
The patent changes the physical-chemical parameters of the rinse solution by using isopropyl alcohol (IPA) instead of traditional water-based solutions, and controls the baking temperature (50-100°C) and duration (5-120 seconds) to optimize drying conditions. These parameter changes prevent fin structure collapse while maintaining pitch reduction benefits.
Solution Approach 2:
The patent utilizes the phase transition of isopropyl alcohol from liquid to vapor during the baking process. The controlled evaporation of IPA at 50-100°C creates a gentle drying effect that avoids sudden surface tension changes which could cause fin structure collapse, thereby maintaining structural stability during pitch reduction.
2Ease of manufacture
If conventional cleaning processes are used after fin formation, then manufacturing simplicity is maintained, but current leakage occurs due to structural failure
Solution Approach 1:
The patent modifies the chemical composition parameter by substituting water-based cleaning solutions with isopropyl alcohol, and adjusts process parameters (temperature 50-100°C, time 5-120 seconds) to achieve effective cleaning without causing fin structure failure, thereby preventing current leakage while maintaining process simplicity.
Solution Approach 2:
The patent uses isopropyl alcohol as a disposable rinse solution that is evaporated during the baking process. This approach eliminates the need for multiple rinsing steps and complex drying procedures, maintaining manufacturing simplicity while preventing the structural failure that leads to current leakage.
3Manufacturing precision
If rinse duration is extended to ensure complete cleaning, then cleaning effectiveness is improved, but fin-shaped structures may fall due to prolonged exposure to liquid
Solution Approach 1:
The patent optimizes the rinse duration parameter to 15-60 seconds with isopropyl alcohol, which is sufficient for effective cleaning but limited enough to prevent fin structure collapse. The subsequent controlled baking process (50-100°C for 5-120 seconds) completes the drying without prolonged liquid exposure, thereby maintaining both cleaning effectiveness and structural integrity.
Solution Approach 2:
The patent creates a continuous process where the isopropyl alcohol rinse is immediately followed by a controlled baking step. This continuous action ensures complete cleaning effectiveness while the gradual evaporation during baking prevents sudden structural failure, maintaining fin integrity throughout the cleaning-drying sequence.
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 method effectively prevents fin-shaped structures from falling during fabrication, enhancing the reliability and performance of FinFET devices by ensuring structural stability and reducing current leakage.
Implementation Method 1
using isopropyl alcohol (IPA) to perform a rinse process
Implementation Method 2
performing a baking process; a temperature of the baking process is between 50° C. to 100° C., and a duration of the baking process is between 5 seconds to 120 seconds
Data Source
AI summary
A method for fabricating semiconductor device includes the steps of: forming fin-shaped structures on a substrate; using isopropyl alcohol (IPA) to perform a rinse process; performing a baking process; and forming a gate oxide layer on the fin-shaped structures. Preferably, a duration of the rinse process is between 15 seconds to 60 seconds, a temperature of the baking process is between 50° C. to 100° C., and a duration of the baking process is between 5 seconds to 120 seconds.