Microwave Radiation Antenna With Segmented Gas Slots
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional microwave plasma processing apparatuses face challenges in achieving uniform plasma formation and preventing microwave power loss and abnormal discharging due to gas conversion into plasma within the shower plate, especially when processing gases are introduced through side walls.
Innovation Solution
A microwave radiation antenna design featuring a conductive antenna body with separated slots for microwave radiation and a gas diffusion space, along with gas outlets, and an annular dielectric member covering the slot formation region, generates a metal surface wave to produce a uniform surface wave plasma while preventing gas conversion into plasma and minimizing power loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a dielectric shower plate with gas holes is used to supply processing gas uniformly, then plasma uniformity is improved, but microwave power loss and abnormal discharging occur due to gas conversion into plasma within the shower plate
Solution Approach 1:
The antenna body is divided into functionally independent regions: a gas diffusion space with gas outlets for uniform gas distribution, and separate microwave radiation slots for microwave transmission. This segmentation prevents gas and microwave paths from overlapping, eliminating plasma formation within the shower plate structure while maintaining uniform gas supply to achieve uniform plasma generation in the processing chamber.
Solution Approach 2:
The gas supply function is extracted from the microwave radiation structure by providing separate gas outlets in the antenna body that are spatially separated from the microwave slots. This allows uniform gas distribution to be achieved through the antenna body structure itself, while the microwave radiation slots remain clear of gas flow paths, preventing power loss and abnormal discharging.
2Ease of operation
If processing gas is supplied from a side wall gas inlet, then gas flow control difficulty arises, but plasma uniformity deteriorates
Solution Approach 1:
The antenna body serves multiple functions simultaneously: it acts as a microwave radiation structure with slots for electromagnetic wave transmission, and as a gas distribution system with diffusion spaces and outlets for uniform processing gas supply. This multi-functionality integrates gas supply and microwave radiation into a single unified structure, achieving both ease of gas flow control and uniform plasma generation.
Solution Approach 2:
The gas supply system and microwave radiation structure are merged into a single integrated antenna body. The gas diffusion space and outlets are incorporated within the antenna body structure itself, combining the functions of gas distribution and microwave transmission in one component, thereby simplifying gas flow control while ensuring uniform plasma formation.
3Loss of energy
If a cover plate with lower dielectric constant is interposed between antenna and shower plate, then power loss is reduced, but gas conversion into plasma cannot be fully prevented
Solution Approach 1:
The antenna body acts as an intermediary structure between the microwave source and the processing chamber. It provides a controlled environment with separate gas diffusion spaces and microwave radiation slots, mediating the interaction between microwave energy and processing gas to prevent uncontrolled plasma formation while allowing efficient microwave transmission for uniform plasma generation.
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 configuration ensures uniform plasma generation and efficient microwave energy transfer, preventing power loss and abnormal discharging, thereby enabling effective plasma processing for semiconductor wafers.
Implementation Method 1
a metal surface wave is formed in the microwave radiation surface by the microwave radiated through the slots and the annular dielectric member and a surface wave plasma is generated by the metal surface wave
Implementation Method 2
By an electric field of the microwave, a surface wave plasma is generated in the chamber
Data Source
AI summary
A microwave radiation antenna includes an antenna body having a microwave radiation surface; a processing gas inlet configured to introduce a processing gas into the antenna body; a gas diffusion space configured to diffuse the processing gas in the antenna body; a plurality of gas outlets provided in the antenna body and configured to discharge the processing gas into the chamber; a plurality of slots provided in the antenna body under a state where the slots are separated from the gas diffusion space and the gas outlets; and an annular dielectric member provided in the microwave radiation surface side of the antenna body to cover a slot formation region where the slots are formed. A metal surface wave is formed in the microwave radiation surface by the microwave radiated through the slots and the annular dielectric member and a surface wave plasma is generated by the metal surface wave.