Thermal Evaporation System for Thin Film Deposition

Thermal Evaporator System

Thermal evaporation is one of the common techniques of Physical Vapor Deposition (PVD) for thin film deposition on the surface of various objects. It is the simplest of the PVD techniques. A thermal evaporation system uses vacuum technology for applying coatings or thin films of pure materials on the object surface for different purposes. A resistive heat source is used for evaporating a solid material in a vacuum chamber to form thin films.

Thermal Evaporator

In a Thermal Evaporator System, the material is heated until vapor pressure is produced and its surface atoms have sufficient energy to leave the surface. At this point, the free atoms in the form of evaporated material, or vapor stream traverse the vacuum chamber at thermal energy (less than 1 eV). This vapor stream hits the substrate material positioned above the evaporating material to deposits a coating or thin film.

Thermal Evaporator 

 Using the thermal evaporation technique, an operator can adjust the system on different parameters to achieve desired results for thickness, uniformity, adhesion strength, stress, grain structure, optical or electrical properties, etc. Some common custom adjustments that a thermal evaporator offers: the ability to hold any shape and size substrate, the capability of multiple evaporation sources, thin-film thickness monitor, pressure adjustment, and cross-contamination shield.

Materials used for Thin Film Deposition in Thermal Evaporator System

The thermal evaporation system can be used for single layer or multi-layer thin films of metals, oxides & nitrides of non-metals, and organic OLEDs. The material to be applied can be in the pure atomic form or can be in the molecular form such as oxides and nitrides. Some common materials used for thin-film depositions are aluminum, chromium, gold, silver, copper, indium, and many more. The substrate on which the thin film is deposited can be semiconductor wafers, solar cells, optical components, or any other material depending on the industrial requirement. 

Some common uses of Thermal Evaporation

• Applying electrical contacts on a substrate by depositing metal thin films such as silver or aluminum.
• Deposit metallic contact layers for thin film devices such as solar cells, thin-film transistors,   and OLEDs
• Depositing thick indium layers for wafer bonding

Thin Film Deposition Services – Things to Know

Thin-film Deposition 

Thin film deposition is the technique of applying a thin layer of material or coating on a surface to form layers to develop filters, create reflective surfaces, increase insulation and conduction for the protection.  An example of thin-film deposition is a mirror where a thin layer of aluminum coating is applied on a sheet of glass in order to make the surface reflective. Thin-film deposition services are at the heart of the semiconductor industries, optical devices industries, compact disk manufacturers, solar panels industries and glass industries. 

The companies that provide thin film deposition services offer a variety of thin-film deposition systems including thermal evaporators, PLD (pulsed laser deposition) systems, electron beam evaporators, TCVD (thermal chemical vapor deposition) systems and more.

There are two methods of thin film deposition: chemical & physical. The method of deposition depends on the purpose of the deposition, thickness desired and material of the surface and the substrate. Manufacturers seeking to apply thin films should consult with the experts to understand the process and methods of thin film deposition. This will help him to choose the best method and system for their industries under expert guidance.

Let’s get the basic understanding of chemical thin film deposition and physical thin film deposition methods.

Chemical Deposition

In the chemical deposition method, a substrate is fully submerged in a volatile chemical fluid that produces a chemical change on a surface to deposit coating. In this method, every surface of the substrate is equally coated with the substance material. Chemical vapor deposition (CVD) is one of the highest-performance examples of chemical deposition methods.

Physical Deposition

This method does not include any kind of chemical reaction; it involves a wide range of technologies including thermodynamic, mechanical or electromechanical processes. In this method to produce a thin film on the substrate, a material is released from a source in a low-pressure environment for accurate results. Thermal evaporation and sputtering are the two most common techniques used in the physical vapor deposition (PVD) method.

According to the requirement of the manufacturer, a host variety of coating options available including metals coating, oxides coating, diamond coating, transparent conductors, insulators and more. If you are a manufacturer and seeking to apply thin films as per your industry standards, you should have well aware of the substance material is being used in your manufacturing plant. You should search and consult with some reputed company involved in thin film deposition services for expert consultation and guidance before choosing the best deposition method and coating type for your industry. 

How Does an Electron Beam Evaporator System Works?

Electron Beam Evaporator System

Electron beam evaporation is a type of physical vapor deposition in which the target material is used as a coating and bombarded with an electron beam from a charged tungsten filament to evaporate and convert it to a gaseous state for deposition on the material to be coated. The electron beam causes atoms from the target material to transform into the gaseous phase.

The materials to be applied with thermal evaporation techniques can be pure atomic elements or can be molecules like oxides and nitrides. The object to be coated is referred to as the substrate and can be in any wide variety of things like in semiconductor wafers, solar cells, optical components or in other possibilities.

Difficulties of direct evaporation to form oxides, nitrides, fluorides, carbides are due to fragmentation of vaporized compounds that can overcome many of these problems. Here metals are evaporated in the presence of reactive gas with a typical reactive evaporation system. The problem here is that most oxides are substoichiometric due to the low energy of the evaporated adatoms due to which deposition rate can suffer.

Evaporation is one of the first processes used extensively for the deposition of thin films and in the process enabled to use of thin films in a wide variety of applications that lowered manufacturing costs and expanded the functionality of bulk materials. Evaporation and related processes are still used extensively to synthesize a wide variety of thin coating.

E beam evaporation is used to deposit a wide variety of materials used for optical thin film applications as laser optics and solar panels to eyeglasses and architectural glass to provide the optical, electrical and mechanical qualities required. It provides high material utilization efficiency as compared to other processes and reduces costs.

Some evaporation systems are delivered with programmable sweep controllers to provide optimal heating of the evaporation materials and minimized contamination from a crucible. Multi-pocket e beam sources can be provided to sequentially evaporate different evaporation materials without breaking vacuum for multilayer film designs. Some systems are configured in a way that is controlled for automated single and multilayer process control.

E – Evaporation the system is controllable, repeatable and compatible with the use of an ion source to enhance the desired thin film offering a better configuration for R and D production, targeting high volume with certain types of applications.

Electron beam evaporator system is better than resistive thermal evaporation which is better than heating materials to much better temperatures which is better for resistive or crucible heater. This allows for very high deposition rates and evaporation of high-temperature materials that can better maintain the purity of the source material. Water cooling also tightly confine the electron beam heating to only the area occupied by the source material, eliminating any unwanted contamination from neighboring components.

E beam evaporation is also available on a number of PVD platforms and in many applications including metallization, dielectric coating, optical coatings, and Josephson junctions

Hot Filament Chemical Vapor Deposition: Useful information!!!

Chemical Vapor Deposition

Hot filament chemical vapor position (HFCVD) is one of the most simple and cost-effective ways in which a large variety of materials can be deposited. In this technique, a resistively heated metallic filament like rhenium, tungsten, or tantalum is made use of for catalytically/thermally dissociating the molecules of the source gas that has been introduced with the aim of producing the requisite reactive precursors. Hot filament CVD proves highly beneficial as against the other CVD techniques that are there. For instance, graphene grown by making use of CVD has captured the interest of many groups purely because it requires low cost for preparation and large-area deposition activities. By making use of the said technique, bi-layer, monolayer, and multiple layer graphene have successfully been grown on Cu foil and that too with high uniformity. 

Hot filament CVD offers many benefits as far as numerous diamond deposition applications are concerned. Diamond deposition done by making use of the hot filament gas at low pressures was the very first method in which nucleation and continuous growth of diamond on substrates were achieved. It can be said that the advanced hot filament CVD technology can successfully deposit high-quality, polycrystalline diamond films on a big range of materials. The benefits of hot filament include gif deposition areas, high deposition rates, low consumption of electrical power, and safe and reliable operations. It can easily provide good output and that too at a highly reasonable cost.   

Among many other uses, hot filament chemical vapor deposition (HFCVD) systems are highly useful in applying diamond coatings onto the tungsten carbide cutting inserts, drills, end mills, and more such parts. Another good thing is that these diamond CVD coatings can easily be applied to pieces and tools of almost every size, configuration, and geometry. Hot filament technology can be used to apply uniform films of diamonds for many applications including the ones with large or uneven surfaces. Typical applications comprise thermal management substrates, semiconductor wafers, titanium electrodes, X-ray windows, flat panel displays, slab diamond, and many more. 

These days HFCVD systems are easy to find in the market. Make sure you find a reliable and reputed seller of the same. A good seller will offer you to have the system fully-customized for the synthesis of nanodiamond coatings, microcrystalline CVD diamond coatings, graphene, CVD diamond films, carbon nanotubes (CNTs), and many other varieties of thin-film coatings. These HFCVD systems can be used in research labs and universities. The best part is that they have certain built-in and tailored features that enable the deposition of high-quality films within just a few hours of the installation of this system.  

Nanodiamond Coatings: Top Reasons to Use Nanoparticles for Surface Coatings

Nanodiamonds, since their inception, are finding their way into different applications like cosmetics, coatings, quantum sensing, tools and equipment, electronics, biomedical, and various others. They are getting immense popularity as they come with several sought-after properties and qualities which cannot be obtained through other materials. While their application is becoming more diverse, their nanodiamond coating application is still highly preferred in the industry. 

So, this post is being shared with you to discuss what nanodiamonds are and what makes them suitable for coating application. 

What are Nanodiamonds?

Technically, carbon nanodiamonds consist of a complex structure as its inner core is made up of diamond and the outer part is made of amorphous carbon shell. They belong to the group of zero-dimensional carbon nanoallotrope and have diamondoid like monocrystalline topology with crystal domains and complex structure.

Generally speaking, they are the diamonds whose size range in nanoscale. The availability of such smaller particles with extreme tough core is definitely an immediate advantage which can be exploited in many ways. The common way of producing nanodiamonds is chemical vapor deposition. 

               

Due to their unique structure, they possess a wide array of unique properties such as:

• Extreme hardness
• High surface area
• Mechanical robustness
• High electrochemical stability
• Excellent thermal conductivity
• Environmental inertness
• Optimum insulating property
• Non-toxicity
• Biocompatibility

What Makes Nanodiamonds Suitable for Coating Applications?

Physical properties like hardness, friction wear and tear properties, and thermal conductivity are now available to the coating industry because of the nanodiamonds. 

Since these properties of nanodiamonds are so different than most materials, engineers need only a small loading of nanoscale diamond particles to dramatically change the properties of existing materials. 

Improvements of up to 60% in surface coating properties such as wear resistance, coefficient of friction and thermal conductivity can be obtained by adding a few percent by weight of nanodiamond material and in some cases as small as 0.1%. 

The improvement in coating performance comes in part from the presence of nanodiamonds - hardwearing particles integrated into the polymers. However, there is also a change in the overall structure of the coating, for instance, the crack structures are finer and smaller in size, surface finish measurement is lower about 85%, and the surface appears smoother and somewhat glossy. 

Therefore, nanodiamond coating is widely preferred for the coating of materials where we need to enhance their properties like strength, wear resistance, abrasion resistance, and durability.  

In nickel and gold electroplating, a high improvement in wear resistance can be achieved with just fractional quantities of nanodiamonds while using agglomerated suspensions. 

The current improvement in nanodiamond-polymer is focused on friction and wear properties to achieve greater results in surface coatings and creating thermally conductive polymers for thermal management applications in LED lighting and electronics. 

Thin Film Deposition System: Is Checklist A Perfect Way To Find The Right System?

thin film deposition systems

When it comes to choosing a thin film deposition system, what approach would be right for you? As a nanodiamond, CVD diamonds, carbon nanotubes (CNTs) or graphene manufacturer, is it more beneficial for you to draw a checklist of necessary tools and hardware for hitting the desired performance specifications? Or, should you focus on the bigger picture i.e. identifying the specifications and requirements according to your applications and field of work and then work with the thin film deposition service provider in order to achieve desired results?

According to various sources, a majority of engineers and laboratory researchers prioritize their system performance and vendor cooperation and collaboration to identify a number of specific things, at least in theory, and then search for vendors who meet maximum criteria present on that checklist. However, in practice, it doesn’t seem so. The professionals follow a different trend when they need thin film coating systems and services for their products. 

Most of the engineers and researchers tend to focus on tool attributes when selecting thin film deposition systems rather than just jumping to overall performance and solutions. With the method of checklist, you might be able to secure the most basic requirements for the system and end up with functional hardware that will serve for R&D or applications. But, you will also be at the risk of your system just doing that - working at minimum efficiency which results in a system that doesn’t follow or have support for key process steps or for scaling the production. 

If you need an optimized thin film deposition system, it would require a shift in the mindset. You should start by specifying the film requirements. This will let you benefit from the experience and knowledge of the vendor or service provider. Instead of treating them just as vendors, nanodiamond manufacturers and engineers must view thin film deposition service provider as a collaboration partner. This would help them know more about the vendor, about the systems and they can easily communicate and figure out if their requirements can be fulfilled by the existing infrastructure, facilities and systems of the service provider.  

So, there is no need to represent a bucket of the list to your solution provider. Rather, identify the problems that need to be solved, requirements that need to be fulfilled and specifications that need to be hit at the forefront. Partner with your service provider on how to optimize your specific application. This way you will truly find the application-specific configuration. This time you need solutions related to thin film deposition system, try to follow this approach instead of the standard –checklist way in order to get what you want. 

How nanodiamonds are impacting the various fields?

Diamond is a magnificent material in various respects and nanodiamond comes with most of the outstanding properties as are found in a bulk diamond. Some of such properties include exceptional hardness, biocompatibility, fluorescence and optical properties, electrical resistance and high thermal conductivity, resistance to harsh environments, and chemical stability. The presence of all these properties is the reason why nanodiamonds are being used across different industries. Discussed below are some best-known applications of nanodiamonds. 

• Of late, nanodiamonds have begun to be used for polishing ceramics, silicon wafer, gems, and surgical knives. Apart from this, nanodiamonds are also used for polishing hard discs, lenses, prisms, etc. in the form of pastes, gels, and slurries. It is utilized as a filler to increase the heat conductivity, strength, optical characteristics, and elasticity of the polymers.

• In recent times, nanodiamond coating of implants and numerous other surgical tools has gained widespread popularity because of the presence of properties such as chemical inertness, low cytotoxicity, and hardness in nanodiamonds. 

• Nanodiamonds are now being used for enhancing thermal conductivity. For this purpose, nanodiamonds are added to a coolant which helps to prevent the existing hot zones within the coolant. Thus, one can conclude that using the nanodiamonds in the form of pastes, glues, and substrates can prove beneficial in avoiding burnout, increasing the speed of size reducing active elements, and enhancing their pliability and reliability. 

• In the field of dentistry, nanodiamonds are used for reconstruction, filling, and veneering. When added to the toothpaste, nanodiamonds play a significant role in getting rid of gum diseases. Apart from this, the preeminent absorption properties of nanodiamonds in simply brilliant and this is the reason why they are also being used in skin care cosmetics such as exfoliators, cleansers, etc. Nanodiamonds have also found their way into eyeliner, nail polishes, lip glosses, and shampoos. 

• Activated charcoal is very popular for its nanoparticle size and adsorption features. In the same manner, nanodiamonds also have excellent adsorptive properties and can retain water nothing less than three times its weight. Every carbon atom which exists on the nanodiamond exterior has at least one free electron which might attach itself to elements such as H, O, or N. Thus, we can conclude that nanodiamonds are excellent adsorbents for platelets, amino acids, proteins, and DNA.

• Nanodiamonds are also utilized as the carriers and delivery vehicles of drugs. They are nontoxic and so, they remain free from attacks by the body’s immune system. They can attach to the various molecules and make it possible to achieve the requisite drug release. Moreover, such a complex does not adversely impact the white blood cells and this is the reason why it is highly beneficial for treating cancer. 

• Nanodiamonds may prove highly effective as gene carriers. Additionally, they may also be used for dispensing an insulin-like growth hormone. 

As you can see, the exceptional properties of nanodiamonds make them a viable option for use in various fields. The fact that it can be produced in high quantity, can be functionalized noncovalently as well as covalently, and as of now, has not exhibited any biohazardous effects further adds to its advantages.