Organometallic Coating Defect Reduction via Segmented Filtration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor manufacturing processes face challenges in achieving low defectivity in radiation patternable coatings, particularly due to metal and particle contamination, which can lead to reduced yield and quality of microelectronic products.
Innovation Solution
The development of a method involving spin coating and dual loop filtration systems to form a radiation sensitive organometallic coating with low defect numbers, using purified monoalkyl tin compositions and controlled delivery to minimize water contact and particle contamination, resulting in a coating with fewer than 1 defect per square centimeter and particle sizes greater than 48 nm.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional coating methods are used, then coating formation is achieved, but high defectivity occurs due to metal and particle contamination
Solution Approach 1:
The delivery system is segmented into multiple components: a reservoir for storing the organometallic solution, a pump for controlled delivery, and a spin coating apparatus. This segmentation allows each component to be optimized for minimizing contamination - the reservoir prevents particle ingress, the pump provides controlled flow, and the spin coating system ensures uniform deposition with minimal defects
Solution Approach 2:
The patent employs an inert atmosphere environment during the coating process to prevent oxidation and contamination of the organometallic solution. The system operates in a controlled atmosphere that excludes moisture and oxygen, thereby preventing the formation of metal oxides and other contaminants that would increase defectivity in the coating
2Manufacturing precision
If filtration is applied to remove particles, then particle contamination is reduced, but processing complexity increases
Solution Approach 1:
The organometallic solution undergoes preliminary filtration before being loaded into the reservoir, and the system includes inline filtration during delivery. This preliminary action removes particles and contaminants before they can affect the coating process, ensuring low defectivity without requiring complex filtration systems during operation
Solution Approach 2:
The system incorporates self-cleaning features where the flow dynamics and pressure gradients automatically prevent particle accumulation in filters and delivery lines. The continuous flow regime prevents particulate buildup, reducing the need for manual intervention and complex maintenance systems
3Manufacturing precision
If water contact is minimized during delivery, then metal contamination is reduced, but delivery system design becomes more complex
Solution Approach 1:
The delivery system operates within an inert atmosphere environment that excludes moisture and oxygen. This prevents water contact with the organometallic solution during delivery, thereby preventing hydrolysis and metal contamination without requiring complex exclusion mechanisms
Solution Approach 2:
An inert gas atmosphere serves as an intermediary medium between the organometallic solution and the external environment. This intermediary prevents direct contact between water/moisture and the sensitive organometallic compounds, eliminating metal contamination while maintaining a simple delivery system design
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 significantly reduces defect rates and improves the quality of semiconductor wafers by minimizing metal and particle contamination, enhancing the fidelity of patterns and increasing the yield of devices that meet specifications.
Implementation Method 1
spin coating a purified radiation sensitive organometallic resist solution onto a wafer using a spin coater system
Implementation Method 2
filtered to contain no more than about 10 particles per mL with a particle size of at least about 70 nm
Data Source
AI summary
In the context of forming radiation patternable structures especially for EUV patterning, wafer structures are described comprising a substrate having a smooth top surface and a radiation sensitive organometallic coating having an average thickness of no more than 100 nm and no more than about 1 defect per square centimeter with a defect size of greater than 48 nm, evaluated with a 3 mm edge exclusion. Corresponding methods for forming a low defect coating comprise spin coating a purified radiation sensitive organometallic resist solution onto a wafer using a spin coater system comprising a delivery line and a delivery nozzle connected to the delivery line to form a coated wafer, and drying the coated wafer to form a radiation sensitive organometallic coating having no more than about 1 defect per square centimeter with a defect size of greater than 48 nm, evaluated with a 3 mm edge exclusion. Methods are provided for improved filtering for particle removal from radiation patternable organometallic resist compositions.