5 Benefits of E-Beam Evaporation / Deposition Systems

Electron beam (e-beam) evaporation, also known as electron beam deposition, is the most versatile and commonly used technique for the physical vapor deposition process. In this technique, the target material is bombarded with an electron beam. The source of the electron beam is a charged tungsten filament. Once the target material is heated and reaches the required temperature, it starts evaporating. The gaseous substance, which is obtained from this evaporation process, is transported to the substrate material and deposited to form a thin coating layer. The deposition is possible here due to the precipitation of vaporized atoms or molecules in a vacuum chamber. 

The whole apparatus that facilitates this e-beam evaporation process is known as the electron beam evaporator system. 

The e-beam deposition technique has several advantages for various applications. Some of them are:

Ideal for metals with high melting point

Since the e-beam deposition/evaporation, the system allows the direct transfer of energy with an electron beam to the target material that needs to be evaporated and deposited on the substrate, it is ideal for metals that have a high melting point. 

Results in higher deposition rates

The e-beam deposition system produces higher deposition rates from 0.1nm per minute to 100nm per minute and is known for allowing higher adhesion to the substrate. This is the reason when you need quality thin coating films with higher density, electron beam deposition system is the first choice. 

Very high material utilization efficiency

The e-beam system heats only the target source material instead of the entire crucible. Therefore, thin films produced by these systems possess a much higher purity level as there occurs a lower degree of contamination from the crucible. This results in very high material utilization efficiency and reduced costs when compared to other physical vapor deposition systems. 

Less damage to substrate

Since the energy of the electron beam is concentrated on the target material rather than the entire vacuum chamber, e-beam evaporation technique minimizes the possibility of heat damage to the substrate. 

Suitable for lift-off masking techniques

With the aid of a multiple crucibles electron beam evaporator, many different layers of coatings from different target materials can be formed without compromising the integrity of the vacuum chamber. Thus, this system can also adapt to several lift-off masking techniques.  

Applications of an electron beam evaporator system

As electron beam evaporator systems can produce thin film coatings with desired conductive, reflective, and transmissive qualities, they are used for:

• Optical thin films
• Laser optics
• Solar panels
• Eyeglasses
• Architectural glass

Besides, an electron beam evaporator system is also highly suitable for a variety of industries right from high-performance aerospace and automotive applications where high temperature and wear resistance are critical to highly durable coatings for cutting tools, chemical barriers, and protection in corrosive environments, such as marine fittings. 

CVD System: A Quick Overview of Chemical Vapor Deposition and its Application

 chemical vapor deposition system

Chemical vapor deposition is a practical method to synthesize well-controlled dimensions and structures with high purity. Whether one needs to develop a single layer, multiple-layer, composite, or finally functional coatings, chemical vapor deposition system is the go-to solution these days.

What does the process of chemical vapor deposition involve?

In CVD system, a single precursor gas flows into a chamber that contains the substrate to be coated. The vapor of reactive compound (an easily volatilized liquid or solid in some cases) is sublimed and then directed to the reaction zone via carrier gas. A thin film is deposited on the substrate surface with the help of a chemical reaction or decomposition of gas mixture or in the vicinity at a fixed temperature. 

The precursors used in the CVD process can be single source or dual source in origin. While single-source precursors are generally used for successive thin film production, dual source precursors involve the interaction between different precursors for synthesis of thin film. 

In both cases, it is vital to transport the gas phase precursors with a carrier gas for the synthesis of thin films.

Most commonly used carrier gases are N₂, He and Ar, especially when highly reactive or pyrophoric compounds are involved in the CVD process. In some cases, reactions involve an energy input from the carrier gas such as H₂ or O₂ enrichment. 

A chemical vapor deposition system must:

• Ensure the controlled transport of the reactant and diluent gases to the reaction zone
• Maintain a defined substrate temperature 
• Safely remove the gaseous by-products

To form thin layers with chemical vapor deposition at atmospheric pressure (APCVD), there are four basic types based on gas flow and operation principles:

• Horizontal tube displacement flow type
• Rotary vertical batch type
• Continuous-deposition type using premixed gas flow
• Continuous-deposition type employing separate gas streams

Any CVD Process, including APCVD, involves the following operations. 

First, the reacting gas is transported to the reactor. Thermal equilibrium temperature is achieved for the gas and then, composition through gas-phase collisions and reactions takes place. Lastly, near-equilibrium species are directed to the reactant surface and surface chemical reactions start to occur to create a thin film.

Here is the summary of the chemical vapor deposition process:

• Active gaseous reactants are created.
• The precursor is transported to the CVD system reactor.
• Gas phase precursor is decomposed to remove gaseous by-products and develop reactive intermediates.
• Gaseous reactants are then directed onto the substrate area.
• Surface diffusion takes place for nucleation and thin-film growth
• Desorption of by-products and mass transport away from the active reactive zone. 

Application of Chemical Vapor Deposition System

CVD systems are used for the synthesis of a variety of thin-film coatings, such as:

• Nanodiamond coatings
• CVD diamond coatings
• Micro-crystalline CVD diamond coatings
• Graphene
• Carbon Nanotubes (CNT) 

Chemical vapor deposition systems are widely used in universities and research laboratories for deposition of high-quality thin films. 

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.