Ultrasonic Metallization With Oscillating Substrate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current metallization techniques in electrolyte solutions face challenges in achieving uniform metallic film deposition at high rates, particularly in deep cavities like TSVs, due to non-uniform energy dosage from ultrasonic agitation and mechanical limitations, leading to inefficiencies in chemical exchange and deposition uniformity.
Innovation Solution
The use of an ultrasonic device in conjunction with a dynamically controlled substrate that oscillates to ensure consistent acoustic energy distribution across the substrate surface, enhancing chemical exchange and deposition uniformity by reducing diffusion boundary layers and preventing byproduct incorporation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If ultrasonic agitation is applied to enhance deposition rate, then chemical exchange rate increases, but energy distribution becomes non-uniform leading to poor deposition uniformity
Solution Approach 1:
The substrate is rotated during ultrasonic agitation to dynamically redistribute the acoustic energy exposure across different regions. This rotational movement ensures that areas receiving higher energy dosage are periodically moved away from the ultrasonic source, while areas receiving lower energy dosage are brought into better exposure, achieving uniform deposition despite the inherently non-uniform ultrasonic field
Solution Approach 2:
The substrate rotation creates a periodic exposure pattern where different regions of the substrate cyclically pass through zones of high and low ultrasonic energy intensity. This periodic motion allows each region to receive an averaged, uniform energy dosage over time, converting the non-uniform spatial distribution into a uniform temporal distribution
2Manufacturing precision
If substrate rotation is used to improve uniformity, then energy distribution becomes more uniform, but deposition rate decreases
Solution Approach 1:
The invention merges two techniques—ultrasonic agitation and substrate rotation—into a single integrated process. The ultrasonic agitation provides the high deposition rate by enhancing mass transport, while the substrate rotation simultaneously ensures uniform energy distribution. The combination of these two mechanisms achieves both high productivity and high uniformity that neither technique can achieve alone
3Productivity
If high deposition rate is achieved in deep cavities, then manufacturing efficiency improves, but byproduct incorporation increases causing void formation
Solution Approach 1:
The substrate rotation is applied from the beginning of the deposition process, continuously preventing byproduct accumulation in deep cavities before they can nucleate voids. This preliminary and continuous action ensures that fresh electrolyte is constantly delivered to cavity regions and byproducts are promptly removed, maintaining high deposition rates without compromising film quality or causing device reliability failures
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 achieves highly uniform and rapid metallic film deposition by maintaining consistent acoustic energy distribution, increasing deposition rates, and preventing byproduct incorporation, thus improving gapfill performance and film quality.
Implementation Method 1
at least one ultrasonic device with an operating frequency and an intensity, disposed in a position in the metallization apparatus
Implementation Method 2
enhancing chemical exchange and deposition uniformity by reducing diffusion boundary layers
Implementation Method 3
the semiconductor substrate is dynamically controlled so that the position of the semiconductor substrate varies at a programmed increment or decrement at each revolution of the substrate
Implementation Method 4
Methods and apparatus for metallization on substrates from electrolyte solutions
Data Source
AI summary
An apparatus for substrate metallization from electrolyte is provided. The apparatus comprises: an immersion cell containing metal salt electrolyte; at least one electrode connecting to at least one power supply; an electrically conductive substrate holder holding at least one substrate to expose a conductive side of the substrate to face the at least one electrode; an oscillating actuator for oscillating the substrate holder with an amplitude and a frequency; at least one ultrasonic device with an operating frequency and an intensity, disposed in the metallization apparatus; at least one ultrasonic power generator connecting to the ultrasonic device; at least one inlet for metal slat electrolyte feeding; and at least one outlet for metal salt electrolyte draining.