Ultrasonic Inline Cleaning of Wire Saws and Cutting Wires

Clean wire surfaces are important when it comes to wire saws and diamond wire saws. Only clean, well-maintained wires produce precise cuts (e.g., silicon wafers, semiconductors, minerals and stones) ans provide high efficiency and quality. Ultrasonic inline wire saw cleaning is the superior technique to clean wire saws in a continuous inline process thereby ensuring permanently fresh cleaned wires for optimum cutting performance.

Cleaning Sawing and Cutting Wires with Ultrasound

During the production of semiconductor boards and silicon wafers as well as for cutting applications in other industries, wire saws and cutting wires are widely used to cut the wafers into thin plates. These sawing and cutting wires (e.g., diamond wire saws, grain wire saws) must be well maintained and kept free from contamination in order to obtained the desired cutting precision and efficiency. Furthermore, only a clean sawing or cutting wire prevents defects and damage of the cut material.
Ultrasonic cleaning using high-performance, low-frequency ultrasound waves, which cause intense turbulences and acoustic cavitation, has been established as a highly reliable technique for the continuous cleaning of endless materials.
Hielscher Ultrasonics’ wire saw cleaning technology applies focused ultrasound via a special designed sonotrode (ultrasonic probe or horn) in a continuous process into a water bath. The cutting or sawing wire is guided along the ultrasound transmitting sonotrode in very close proximity thereby passing through the intense cavitation hot zone. The high amplitudes and the focused sonication via ultrasonic sonotrode ensures high efficiency and excels ultrasonic cleaning tanks by far. (Click here to read more about the lack of cavitation in ultrasonic cleaning baths and tanks!) The cavitational hot zone beneath the sonotrode is characterized by intense turbulences, shear stress, high pressures and temperatures and respective differentials as well as liquid jets. These intense forces remove dust, dirt and contaminating particles from the cutting wires and disperse them in the water bath, where the particles get flushed away.

Technical scheme of ultrasonic inline cleaning system integrated into wire saw machine

Improved Cleaning of Wire Saws and Cutting Wires with Ultrasonics

Hielscher’s ultrasonic cleaning technology provides substantial improvements to industries that use wire saws (e.g., diamond wire cutting) – including wafer cutting in the semiconductor and photovoltaic industry. By ultrasonic cavitation, any cutting wires such as diamond-impregnated wires are cleaned very efficiently. On the on hand, cleaner cutting wires results in cleaner cuts. Thereby a higher product quality and lower reject rates during production are achieved. On the other hand, the intensively cleaned wire is capable to be operated at higher cutting frequency, which allows for faster cutting and a more efficient system utilization as well as higher levels of production efficiency.
In the photovoltaic and semiconductor industry, for wafer cutting mainly diamond wires are used due to their high cutting capability and efficiency as well as for its abrasion resistance. Cutting materials such as silicon wafers (e.g. monocrystalline silicon) is a mechanical separation process, which causes friction and heat. Due to the friction and material wear, particles such as dust and debris remain on the surface of the cutting wire. Such contamination can result in in-precise cuts, surface damage and defects.
Ultrasound is well known for its capabilities in the cleaning of metal parts. There are two working principles. Firstly, there is an oscillation of the cleaning liquid itself that causes a movement of the liquid in relation to the parts to be cleaned. Secondly – and more important – is the cavitation caused by high amplitudes. Both of these ultrasonics effects generate intense and reliable cleaning of endless materials.

Why Ultrasonic Cleaning of Wire Saws?

Saw and cutting wires are widely used in industry due to the precision of cuts and the smaller kerf (i.e., the width of the saw cut). However, in order to obtain this precision of cutting, the wire must be free from contamination since any surface imperfections may cause errors in the cut. Contaminations mostly result from the cutting process itself, which makes continuous cleaning of wire saws essential.
The cleaning process of the wire saw (e.g., diamond-impregnated cutting wire, high-precision wire saws) requires an effective cleaning without damaging the surface of the wire saw. Any loss of sharpness must be avoided whilst removing dust and dirt efficiently.
Ultrasonic inline cleaning is the perfect solution for the continuous cleaning of precision wire saws. Hielscher ultrasonic inline cleaning systems remove dirt and dust in a contact-less, yet intense mechanical cleaning. The working principle of ultrasonic inline cleaning of endless materials such as cutting wires is based on the phenomenon of acoustic cavitation. Hielscher ultrasonic inline cleaning systems feature a specially designed sonotrode, which is inserted in to a water bath. The cutting wire passes the sonotrode in close proximity. The sonotrode transmits amplitudes into the cleaning water bath generating acoustic cavitation. The water bath flushes the dirt particles away; the particles can be filtered out using an optionally available belt filter.

How Does Cleaning Using Ultrasonic Cavitation Work?

Acoustic cavitation is characterized by intense vibrations, high temperatures and pressures and respective differentials as well as shear forces and liquid jets. These intense cavitational forces remove dust and dirt from the cutting wire surface leading to continuously high cutting efficiency and precision.
Contact-Less Cleaning: The wire saw is not in contact with abrasive cleaning tools, but is instead cleaned by ultrasonically agitated water. Thereby, the Hielscher ultrasonic cleaning technology prevents any destruction of the wire surface.

Why Should I Clean My Wire Saws Using Ultrasonic Inline Cleaning?

Due to the efficient and intense cleaning in continuous inline mode, the cutting precision and quality is significantly improved:

• more precise cutting, e.g. for thinner wafers
• preciser cuts result in less waste
• faster cutting speed allows for higher production capacity per wire saw machine
• improved wafer surface
• longer life cycle of the cutting wire / wire saw
• suitable for all materials at any scale in any production

Hielscher Ultrasonics’ High-Performance Inline Cleaning Systems

Depending on the required cleaning intensity, Hielscher offers ultrasonic transducers with various ultrasonic power (e.g. the 200W system UP200St or the 1kW ultrasonicator UIP1000hdT) for the integration into wire saw machines of any kind. Hielscher high-performance ultrasonic transducers fulfil industrial grade, are built for 24/7/365 operation and can be reliably run in rough environments under heavy duty conditions for continuous cleaning of endless wires.
Being versatile and easy to handle, Hielscher ultrasonic transducers can be mounted in various angles and in small spaces. Standard systems as well as customized ultrasonicators are available in order to fulfil your demands.

Ultrasonic Cleaning Modules as OEM

Are you manufacturer of wire saw systems and want to integrate Hielscher ultrasonics inline cleaning modules? Contact us to get in touch with our R&D team to discuss the specific requirements. Whether you plan an installation in small spaces or retro-fitting into existing wire saw systems, our Hielscher cleaning modules will match your requirements.