Ampoule Bypass Line for MOCVD Precursor Residue Removal

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In metal-organic chemical vapor deposition (MOCVD) processes, residual precursor vapor in the delivery line is not efficiently removed, leading to accumulation and contamination of deposited films due to the instability of metal-organic precursors, which decompose at low temperatures and form particulates if not promptly managed.

Innovation Solution

The implementation of a valve configuration in the ampoule lid with a bypass line connecting the inlet and outlet pneumatic valves allows for the complete removal of residual precursor vapors by flowing a purge gas through the tubes, diverting the outlet gas directly or through the process chamber, facilitating faster removal with pressure drops.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the ampoule outlet pneumatic valve is closed to stop precursor delivery, then the deposition process can be controlled, but residual precursor vapor accumulates in the delivery line and contaminates the deposited film

Engineering Contradiction:

Improvedeposition qualityVSAvoidresidual precursor accumulation

Core Design Contradiction:

Manufacturing precisionVSObject-generated harmful factors

Solution Approach 1:

The patent extracts the harmful residual precursor vapor from the delivery line by introducing a separate purge gas flow path. The purge gas flows through the delivery line to carry out the residual precursor vapor, effectively separating the precursor removal function from the main deposition process and preventing contamination of the deposited film.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces purge gas as an intermediary substance to mediate the removal of residual precursor vapor. The purge gas acts as a carrier that transports the harmful precursor vapor out of the delivery line without interfering with the controlled deposition process in the processing chamber.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Stability of the object's composition

If thermal control is applied to keep the delivery line above dew point, then precursor vapor stability is maintained, but residual precursor still accumulates and forms particulates

Engineering Contradiction:

Improveprecursor vapor stabilityVSAvoidparticulate formation

Core Design Contradiction:

Stability of the object's compositionVSObject-generated harmful factors

Solution Approach 1:

The patent implements continuous purge gas flow through the delivery line during and after the deposition process. This continuous action ensures that residual precursor vapor is constantly removed and prevented from accumulating, thereby preventing particulate formation even when thermal control alone is insufficient.

Inventive Principle:

Principle #20Continuity of useful action

Solution Approach 2:

The patent changes the flow dynamics parameter by introducing purge gas flow through the delivery line. This creates a positive pressure gradient that actively pushes residual precursor vapor out of the line, complementing the thermal control approach and preventing the temperature drops that lead to particulate formation.

Inventive Principle:

Principle #35Parameter changes

3Object-generated harmful factors

If purge gas flow is used to remove residual precursor, then contamination is reduced, but additional gas flow requirements increase system complexity

Engineering Contradiction:

Improvefilm contaminationVSAvoidgas flow control system

Core Design Contradiction:

Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The patent designs the valve cluster to serve multiple functions: controlling precursor delivery to the processing chamber, directing purge gas flow through the delivery line, and managing exhaust flow. This multi-functionality reduces the need for separate dedicated components for each function, thereby limiting the increase in system complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the precursor delivery path and the purge gas flow path through the same delivery line, using a valve cluster to control the flow direction. This consolidation of flow paths into a single line with controlled switching reduces the number of separate components needed compared to having entirely separate delivery and purge systems.

Inventive Principle:

Principle #5Merging (Combining)

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 enables rapid removal of residual precursor vapors, reducing particle formation and contamination, and extends the life of valve seals by preventing precursor stagnation, thus maintaining process control and improving deposition quality.

Implementation Method 1

facilitating faster removal with pressure drops

Methodology Applied

Scientific EffectPressure gradient: Pressure Gradient

Data Source

PatentUS10752990B2Apparatus and methods to remove residual precursor inside gas lines post-deposition

Publication Date: 2020.08.25 APPLIED MATERIALS INC

AI summary

Apparatus and methods for supplying a gas to a processing chamber are described. The apparatus comprises an inlet line and an outlet line, each with two valves, in fluid communication an ampoule. A bypass line connects the inlet valve and outlet valve closest to the ampoule. The apparatus and methods of use allow a precursor residue to be removed from the delivery lines of a processing chamber.