Evaluation of Megasonic Cleaning for Sub-90nm Technologies

2005 ◽  
Vol 103-104 ◽  
pp. 141-146 ◽  
Author(s):  
Guy Vereecke ◽  
Frank Holsteyns ◽  
Sophia Arnauts ◽  
S. Beckx ◽  
P. Jaenen ◽  
...  
Keyword(s):  
Low Temperature ◽  
Mass Balance ◽  
Semiconductor Manufacturing ◽  
Particle Removal ◽  
Dissolved Gas ◽  
Cleaning Efficiency ◽  
Megasonic Cleaning ◽  
High Particle ◽  
The Cost

Cleaning of nanoparticles (< 50nm ) is becoming a major challenge in semiconductor manufacturing and the future use of traditional methods, such as megasonic cleaning, is questioned. In this paper the capability of megasonic cleaning to remove nanoparticles without inflicting damage to fragile structures is investigated. The role of dissolved gas in cleaning efficiency indicates that cavitation is the main cleaning mechanism. Consequently gas mass-balance analyses are needed to optimize the performance of cleaning tools. When gas is dissolved in the cleaning present tools can remove nanoparticles down to about 30 nm using dilute chemistries at low temperature. Ultimate performance is limited by cleaning uniformity, which depends on tool design and operation. However no tool reached the target of high particle removal efficiency andlow damage. Significantly lower damage could only be obtained by decreasing the power, at the cost of a lower cleaning efficiency for nanoparticles. The development of damage-free megasonic is discussed.

Post-CMP Megasonic Cleaning Using Dilute SCI Solution

1999 ◽  
Vol 566 ◽  
Author(s):  
A. A. Busnaina ◽  
N. Moumen ◽  
J. Piboontum ◽  
M. Guarrera
Keyword(s):  
High Frequency ◽  
Semiconductor Manufacturing ◽  
Acoustic Streaming ◽  
Wafer Surface ◽  
Particle Removal ◽  
Optimum Conditions ◽  
Small Particles ◽  
Cleaning Efficiency ◽  
Megasonic Cleaning ◽  
Thermal Oxide

Non contact cleaning or wet-cleaning processes, were the megasonic play a key role in the separation of the particles from the wafer is a commonly used technique in semiconductor manufacturing. CMP process can be very damaging to the production yield if not followed by an effective post clean process. McQueen identified the effect of the acoustic boundary layer and its role in the removal of small particles at high frequency. Busnaina et alt studied ultrasonic and megasonic particle removal and the effect of acoustic streaming. They showed that the cleaning efficiency increased with power until a certain range and then decrease slightly. Busnaina et al result indicted that SCI removes more particles than DI water particularly at lower megasonic powers specially in the case were the slurry particles are deposited onto the wafer surface by dipping experiments. But they also demonstrated that it was possible to achieve 100 % removal in DI water when using the optimum conditions. This paper presents the latest results of the post-CMP megasonic cleaning process, this study is focused on the cleaning of thermal oxide silicone wafer polished using silica based slurry and cleaned using diluted SC1 (H20/H202/NH4OH: 40/2/1).

Effects of Chamber Pressure on the Performance of CO2 Beam Cleaning

2014 ◽  
Vol 219 ◽  
pp. 131-133
Author(s):  
Seung Ho Kim ◽  
Joong Ha Lee ◽  
Ho Young Kim
Keyword(s):  
Semiconductor Manufacturing ◽  
Manufacturing Industry ◽  
Supersonic Nozzle ◽  
Solid Particles ◽  
Chamber Pressure ◽  
Megasonic Cleaning ◽  
Functional Patterns ◽  
Induce Pattern ◽  
Cleaning Methods ◽  
The Cost

As the size of functional patterns in the semiconductor chips shrinks down to below 100 nm, removing nanoscale contaminant particles is an important technological challenge that the current semiconductor manufacturing industry must overcome. Several cleaning methods proposed to date, such as megasonic cleaning [1], droplet impact [2], and cryogenic aerosol cleaning [3], have difficulties in cleaning of sub-100 nm contaminant particles, let alone their tendency to induce pattern damages. Kim et al. [4] has recently developed a new method, where CO2 solid particles nucleated from a supersonic nozzle physically attack contaminant nanoscale particles on the wafer, thus detaching them. A drawback of this novel scheme is that the cleaning must be executed in vacuum because CO2 gas needs to sublimate into solid and be accelerated supersonically as exiting the nozzle. This has adverse effects on the cost and rate of the semiconductor manufacturing process. Here we investigate the effects of vacuum chamber pressure on the performance of the CO2 dry cleaning system. We observe the cryogenic CO2 beams, dents induced by CO2 solid particles, and wafer surfaces initially contaminated with cerium oxide particles, which indicate the effects of the chamber pressure.

Removal of Submicron Particles Using High Frequency Ultrasonics

1996 ◽  
Author(s):  
Ahmed A. Busnaina ◽  
Fen Dai
Keyword(s):  
High Frequency ◽  
Semiconductor Manufacturing ◽  
Submicron Particles ◽  
Particle Removal ◽  
Cleaning Process ◽  
Submicron Particle ◽  
New Techniques ◽  
Megasonic Cleaning ◽  
Ultrasonic Cleaning ◽  
Particulate Contamination

Abstract High-frequency ultrasonic cleaning is widely used in the semiconductor and other industries affected by contamination for the removal of particulate contamination. High frequency (near 1 MHz) ultrasonic cleaning (known as megasonic cleaning) is specially used in semiconductor manufacturing [1]. Many studies concerning submicron particle removal using megasonic and ultrasonic cleaning has been conducted recently [2–7]. The megsonic cleaning process proved to be the essential processes in cleaning silicon wafers after processes such as CMP, RIE, CVD, Sputter, etc. This paper introduces recent results that involve new techniques for introducing the ultrasonic energy in the cleaning bath.

Scanning Probe Microscopy Imaging before and after Atomic Layer Oxide Deposition on a Compound Semiconductor Surface

2012 ◽  
Vol 187 ◽  
pp. 9-10
Author(s):  
W. Melitz ◽  
J.B. Clemens ◽  
J. Shen ◽  
E.A. Chagarov ◽  
S. Lee ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Atomic Layer ◽  
Semiconductor Surface ◽  
Angle Of Incidence ◽  
Particle Removal ◽  
Cleaning Efficiency ◽  
Microscopy Imaging ◽  
Megasonic Cleaning ◽  
Before And After ◽  
Oxide Deposition

The megasonic cleaning efficiency is evaluated as a function of the angle of incidence of acoustic waves on a Si wafer. Acoustic Schlichting streaming alone is not able to remove nanoparticles smaller than 400 nm. It is shown that oscillating or collapsing behavior of bubbles are responsible for removing nanoparticles smaller than 400 nm during a cleaning process with ultrasound. Optimal particle removal efficiency is obtained around the angle of acoustic transmission of the silicon wafer.

The Influence of the Angle of Incidence in Megasonic Cleaning

2012 ◽  
Vol 187 ◽  
pp. 163-166 ◽  
Author(s):  
Steven Brems ◽  
Marc Hauptmann ◽  
Elisabeth Camerotto ◽  
Xiu Mei Xu ◽  
Stefan De Gendt ◽  
...  
Keyword(s):  
Silicon Wafer ◽  
Acoustic Waves ◽  
Angle Of Incidence ◽  
Particle Removal ◽  
Cleaning Process ◽  
Acoustic Transmission ◽  
Cleaning Efficiency ◽  
Megasonic Cleaning ◽  
Schlichting Streaming ◽  
Si Wafer

The megasonic cleaning efficiency is evaluated as a function of the angle of incidence of acoustic waves on a Si wafer. Acoustic Schlichting streaming alone is not able to remove nanoparticles smaller than 400 nm. It is shown that oscillating or collapsing behavior of bubbles are responsible for removing nanoparticles smaller than 400 nm during a cleaning process with ultrasound. Optimal particle removal efficiency is obtained around the angle of acoustic transmission of the silicon wafer.

Acoustic Field Analysis of a T Type Waveguide in Single Wafer Megasonic Cleaning and its Effect on Particle Removal

2007 ◽  
Vol 134 ◽  
pp. 229-232 ◽  
Author(s):  
Yang Lae Lee ◽  
Eui Su Lim ◽  
Kook Jin Kang ◽  
Hyun Se Kim ◽  
Tae Gon Kim ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Acoustic Pressure ◽  
Field Analysis ◽  
Particle Removal ◽  
Pressure Measurements ◽  
Cleaning Efficiency ◽  
Transverse Waves ◽  
Megasonic Cleaning ◽  
Longitudinal Waves ◽  
Wafer Cleaning

T type megasonic waveguide was analyzed by finite element method (FEM), acoustic pressure measurements and particle removal efficiency for the single wafer cleaning application. Compared to conventional longitudinal waves, a transverse waves were generated in a T type waveguide. Not like longitudinal waves, transverse waves showed changes of direction and phase which increased the cleaning efficiency.

Noncontact Physical Removal of Nano-Scale Particles From Surfaces

2001 ◽  
Author(s):  
Ahmed A. Busnaina ◽  
Hong Lin
Keyword(s):  
Semiconductor Manufacturing ◽  
Pressure Fluctuations ◽  
Acoustic Streaming ◽  
Particle Removal ◽  
Cleaning Process ◽  
Sound Waves ◽  
Megasonic Cleaning ◽  
Nano Scale ◽  
Technology Roadmap ◽  
Sonic Energy

Abstract With the International Technology Roadmap for Semiconductors decreasing the particle removal requirements from 125nm (0.3–0.75/cm2) in 1997 to 25nm (0.01–0.15/cm2) in 2011, an era of the most challenging cleaning applications in semiconductor manufacturing is upon us [1. Megasonic cleaning is a widely used non-contact cleaning technique. In megasonic cleaning, wafers are immersed in a cleaning liquid medium to which sonic energy is applied. High intensity sound waves generate pressure fluctuations and acoustic streaming which detach the particles from the surface and remove them. Busnaina et al [2–3 studied megasonic particle removal and the effect of acoustic streaming on the cleaning process especially in post-CMP applications. It is important to know the advantage and the limitation of megasonic cleaning technique in nano-scale particles removal.

Exploratory Materials and Devices to Advance CMOS beyond the Classical Si Roadmap

2012 ◽  
Vol 187 ◽  
pp. 3-5 ◽  
Author(s):  
Marc M. Heyns
Keyword(s):  
Silicon Wafer ◽  
Acoustic Waves ◽  
Angle Of Incidence ◽  
Particle Removal ◽  
Cleaning Process ◽  
Acoustic Transmission ◽  
Cleaning Efficiency ◽  
Megasonic Cleaning ◽  
Schlichting Streaming ◽  
Si Wafer

The megasonic cleaning efficiency is evaluated as a function of the angle of incidence of acoustic waves on a Si wafer. Acoustic Schlichting streaming alone is not able to remove nanoparticles smaller than 400 nm. It is shown that oscillating or collapsing behavior of bubbles are responsible for removing nanoparticles smaller than 400 nm during a cleaning process with ultrasound. Optimal particle removal efficiency is obtained around the angle of acoustic transmission of the silicon wafer.

Scalable Particle Removal for sub-5 nm Nodes

2021 ◽  
Vol 314 ◽  
pp. 222-227
Author(s):  
Yukifumi Yoshida ◽  
Katsuya Akiyama ◽  
Song Zhang ◽  
Dai Ueda ◽  
Masaki Inaba ◽  
...  
Keyword(s):  
Polymer Film ◽  
Removal Efficiency ◽  
Particle Removal ◽  
Feature Size ◽  
Megasonic Cleaning ◽  
3D Structures ◽  
High Particle ◽  
Removal Technology ◽  
Induce Pattern ◽  
Cleaning Methods

Wet cleaning has become challenging as the feature size of semiconductor devices decreased to sub-5 nm nodes. One of the key challenges is removing various types and sizes of particles and contamination from complex and fragile 3D structures without pattern damage and film loss. Conventional physical cleaning methods, such as dual-fluid spray or megasonic cleaning, are being used for the particle removal process. However, in advanced device nodes, these methods induce pattern damage and film loss. In this paper, we describe a novel particle removal technology called Nanolift which uses a polymer film consisting of two organic resins with different functions and achieved high particle removal efficiency on various types and sizes of particles with no pattern damage and minimum film loss.

Hostile Takeovers and Anti-takeover Defenses in the Russian Corporate Market

2007 ◽  
pp. 70-84 ◽  
Author(s):  
E. Demidova
Keyword(s):  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Benefit Analysis ◽  
Costs And Benefits ◽  
Hostile Takeovers ◽  
Russian Market ◽  
Takeover Defenses ◽  
The Cost ◽  
European Markets

This article analyzes definitions and the role of hostile takeovers at the Russian and European markets for corporate control. It develops the methodology of assessing the efficiency of anti-takeover defenses adapted to the conditions of the Russian market. The paper uses the cost-benefit analysis, where the costs and benefits of the pre-bid and post-bid defenses are compared.

Sign in / Sign up

Export Citation Format

Share Document