Gigasonic Cleaning for Semiconductor Recesses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ultrasonic cleaning techniques can damage modern integrated circuits due to cavitation, which is ineffective at small feature sizes and fails to penetrate recesses of modern small-scale features, leading to device failures and performance degradation.
Innovation Solution
Gigasonic cleaning techniques utilize high-frequency gigahertz range mechanical waves without cavitation, providing a streamlined flow velocity to effectively remove contaminants from semiconductor wafers with smaller wavelengths, allowing for thorough cleaning of tightly adhered or embedded particles without damaging small-scale features.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional ultrasonic cleaning techniques are used, then cleaning action is provided through cavitation, but damage occurs to small-scale features and particles remain in recesses
Solution Approach 1:
The patent changes the frequency parameter from conventional ultrasonic ranges (20-100 kHz) to gigasonic range (above 1 GHz). This parameter change fundamentally alters the cleaning mechanism from cavitation-based to streamlined flow-based, eliminating damage to small features while improving particle removal effectiveness from recesses
Solution Approach 2:
The patent replaces the cavitation-based mechanical cleaning mechanism with a streamlined flow-based mechanism. By using gigasonic frequencies, the cleaning action transitions from violent bubble collapse to gentle but effective fluid flow that penetrates recesses without damaging small-scale features
2Manufacturing precision
If ultrasonic cleaning with cavitation is applied, then particles can be removed, but small-scale features are damaged
Solution Approach 1:
By changing the frequency parameter to gigasonic range (>1 GHz), the patent eliminates cavitation while maintaining particle removal capability. The streamlined flow generated at these frequencies provides effective particle removal without the harmful cavitation bubbles that damage small-scale features
Solution Approach 2:
The patent converts the harmful cavitation effect into a beneficial streamlined flow. By operating at gigasonic frequencies, the energy that would normally create damaging cavitation bubbles is instead converted into a controlled streamlined flow that effectively removes particles while protecting sensitive features
3Length of stationary object
If conventional cleaning frequencies are used, then cavitation occurs, but penetration into small recesses is insufficient
Solution Approach 1:
The patent changes the frequency parameter to gigasonic range, which fundamentally improves penetration into small recesses. The resulting streamlined flow at these frequencies can penetrate deep into narrow features and remove particles that conventional ultrasonic cleaning cannot reach
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
Gigasonic cleaning limits damage to semiconductor devices, enables reliable removal of smaller particles from smaller recesses, and reduces the risk of surface etching, ensuring the integrity and performance of modern ICs by avoiding the drawbacks of conventional ultrasonic cleaning.
Implementation Method 1
a transducer is provided to transform the electrical signal to a mechanical wave of pressure and displacement that propagates through the cleaning solution with oscillations within the range of gigahertz frequencies
Data Source
AI summary
The present disclosure provides a semiconductor cleaning system. The cleaning system includes a chamber to retain a cleaning solution, and a gigasonic frequency generator. The gigasonic frequency generator is configured to generate an electrical signal corresponding to a range of gigahertz frequencies. A transducer is configured to transform the electrical signal to a mechanical wave of pressure and displacement that propagates through the cleaning solution with oscillations within the range of gigahertz frequencies.