EUV Beam Adjusting Apparatus with Reversed Mirror Pairs

Solution Overview

Problem

Conventional beam adjusting apparatuses for EUV light generating systems face challenges in maintaining the beam diameter and output direction of pulsed laser beams during diverging angle adjustments, leading to potential energy loss or damage to optical elements.

Innovation Solution

The proposed solution involves a beam adjusting apparatus with a specific configuration of concave and convex mirrors, where the order of the second pair of mirrors is reversed relative to the first pair, and a moving apparatus that simultaneously adjusts the distances between these mirrors, allowing for precise control of the diverging angle without significant changes in beam diameter or output direction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional beam adjusting apparatuses adjust the diverging angle of pulsed laser beams, then the diverging angle is modified, but the beam diameter and output direction change, leading to energy loss or damage to optical elements

Engineering Contradiction:

Improvediverging angle adjustmentVSAvoidlaser beam energy loss

Core Design Contradiction:

Adaptability or versatilityVSLoss of energy

Solution Approach 1:

The beam adjusting apparatus is divided into two independent pairs of mirrors (first pair: concave mirror 631 and convex mirror 632; second pair: convex mirror 633 and concave mirror 634). Each pair can adjust the diverging angle independently while the other maintains beam parameters, allowing selective adjustment without affecting overall beam characteristics.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second pair of mirrors is arranged in reverse order compared to the first pair. This inverted configuration allows the second pair to compensate for changes in beam diameter and output direction caused by the first pair, effectively decoupling diverging angle adjustment from unwanted parameter changes.

Inventive Principle:

Principle #13The other way round (Inversion)

2Adaptability or versatility

If conventional beam adjusting apparatuses adjust the diverging angle of pulsed laser beams, then the diverging angle is modified, but the beam diameter and output direction change, leading to damage to optical elements

Engineering Contradiction:

Improvediverging angle adjustmentVSAvoiddamage to optical elements

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The beam adjusting apparatus is divided into two independent pairs of mirrors (first pair: concave mirror 631 and convex mirror 632; second pair: convex mirror 633 and concave mirror 634). Each pair can adjust the diverging angle independently while the other maintains beam parameters, allowing selective adjustment without affecting overall beam characteristics.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second pair of mirrors is arranged in reverse order compared to the first pair. This inverted configuration allows the second pair to compensate for changes in beam diameter and output direction caused by the first pair, effectively decoupling diverging angle adjustment from unwanted parameter changes.

Inventive Principle:

Principle #13The other way round (Inversion)

3Adaptability or versatility

If beam parameters change during diverging angle adjustment, then the diverging angle is modified, but the irradiation conditions onto the target are not maintained

Engineering Contradiction:

Improvediverging angle adjustmentVSAvoidirradiation condition stability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The beam adjusting apparatus is divided into two independent pairs of mirrors (first pair: concave mirror 631 and convex mirror 632; second pair: convex mirror 633 and concave mirror 634). Each pair can adjust the diverging angle independently while the other maintains beam parameters, allowing selective adjustment without affecting overall beam characteristics.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second pair of mirrors is arranged in reverse order compared to the first pair. This inverted configuration allows the second pair to compensate for changes in beam diameter and output direction caused by the first pair, effectively decoupling diverging angle adjustment from unwanted parameter changes.

Inventive Principle:

Principle #13The other way round (Inversion)

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 effectively maintains the irradiation conditions of the pulsed laser beam onto the target, reducing energy loss and minimizing the risk of damage to optical elements, while allowing for precise adjustments of the diverging angle.

Implementation Method 1

irradiates a target with a pulsed laser beam output from a laser apparatus to generate plasma, thereby generating extreme ultraviolet light

Methodology Applied

Scientific EffectLaser ablation: Laser Ablation

Implementation Method 2

generate plasma, thereby generating extreme ultraviolet light

Methodology Applied

Scientific EffectPlasma: Plasma

Implementation Method 3

a first pair of mirrors constituted by a first concave mirror and a first convex mirror, provided along the optical path of the pulsed laser beam

Methodology Applied

Scientific EffectReflection: Reflection

Data Source

PatentUS10374381B2Extreme ultraviolet light generating apparatus

Publication Date: 2019.08.06 GIGAPHOTON INC

AI summary

A beam adjusting apparatus of an extreme ultraviolet light generating apparatus may include: a first pair of mirrors constituted by a first concave mirror and a first convex mirror, provided along the optical path of the pulsed laser beam; a second pair of mirrors constituted by a second concave mirror and a second convex mirror, which are arranged in an order reversed from the order of arrangement of the first concave mirror and the first convex mirror, provided along the optical path of the pulsed laser beam downstream from the first pair of mirrors; and a moving apparatus configured to simultaneously increase or simultaneously decrease the distance between the first concave mirror and the first convex mirror and the distance between the second concave mirror and the second convex mirror.