High-Aspect Ratio Interconnect Development via Centrifugal Refresh

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for developing high-aspect ratio apertures in thick photoresists are limited by slow mass transfer, which hinders the formation of deep metal structures and interconnects, and may cause photoresist delamination due to ultrasonic agitation.

Innovation Solution

A method and apparatus involving a rotatable shaft and substrate fixtures immersed in a developer solution, where the substrates are cyclically rotated to create centrifugal forces that expel dissolution products and introduce fresh developer, optimizing the development process without delamination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If bulk agitation or localized ultrasonic agitation is increased to increase mass transfer, then mass transfer rate is improved, but photoresist delamination occurs

Engineering Contradiction:

Improvemass transfer rateVSAvoidphotoresist delamination

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies ultrasonic vibration at the aperture level to enhance mass transfer and prevent delamination through controlled cavitation effects

Inventive Principle:

Principle #18Mechanical vibration

Solution Approach 2:

The patent replaces bulk mechanical agitation with localized ultrasonic field application, substituting mechanical stirring with acoustic field-induced mass transfer enhancement

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If diffusion is relied upon for mass transfer into high-aspect ratio apertures, then photoresist delamination is avoided, but mass transfer is too slow to be practical

Engineering Contradiction:

Improvephotoresist integrityVSAvoidmass transfer rate

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

Ultrasonic vibration is applied to create cavitation bubbles that collapse and generate microjets, enhancing mass transfer into deep apertures without mechanical contact

Inventive Principle:

Principle #18Mechanical vibration

Solution Approach 2:

The patent utilizes phase transition of developer material during ultrasonic cavitation (liquid to vapor bubble formation and collapse) to drive mass transfer into the aperture

Inventive Principle:

Principle #36Phase transitions

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 enhances the development of high-aspect ratio apertures by increasing the rate of mass transfer, reducing development time, and allowing for deeper apertures without delamination, enabling aspect ratios up to 100:1.

Implementation Method 1

cyclically rotated to create centrifugal forces that expel dissolution products and introduce fresh developer

Methodology Applied

Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentUS11822249B2Method and apparatus to develop lithographically defined high aspect ratio interconnects

Publication Date: 2023.11.21 INTEL CORP

AI summary

Disclosed is a method to develop lithographically defined high aspect ratio interconnects. Also disclosed is an apparatus comprising at least one vessel having a bottom and at least one sidewall extending from the bottom, wherein the at least one sidewall encloses an interior of the at least one vessel, a shaft having a proximal end and a distal end, wherein the distal end of the shaft extends into the interior of the at least one vessel, wherein the proximal end of the shaft is coupled to a motor, at least one support structure which extends laterally from the shaft, and a substrate attachment fixture on a distal end of the at least one support structure, wherein the at least one support structure and the substrate attachment fixture are within the interior of the at least one vessel.