Month: January 2019

Two Methods for Preparing NiCrSi High Resistance Sputtering Target

NiCrSi high-resistance sputtering targets are mainly used to prepare metal film resistors and metal oxide film high resistance resistors, integrated circuit wiring and sensors. These devices are very important in electronic computers, communication instruments, and electronic switches. Due to its excellent performance, resistors made from NiCrSi high-resistance sputtering targets have gradually become a new generation of universal resistors that replace carbon film resistors. Here are two methods for preparing NiCrSi high-resistance sputtering targets.

Adding rare earth metals to improve the target performance

Raw materials: chromium and nickel with an elemental purity greater than 99.5%; silicon with an elemental purity greater than 99.9%; rare earth metals with a mixture purity greater than 98%.

  • Step 1: Smelt Ni, Cr and a small amount of Si into an intermediate NiCrSi alloy. The voltage during the melting of the electric arc furnace is 20V, the current is 500~600A, and the time is 2~5min.
  • Step 2: Place the prepared intermediate NiCrSi alloy was in the bottom of the feeder in a vacuum induction melting furnace. Add the refractory Si material after the intermediate alloy is melted. The vacuum degree during vacuum induction melting is 2 × 10 -2 torr, the power is 35 kW, and the time is 1 h.
  • Step 3: Refining. The power is 20 kW and the time is 30 min.
  • Step 4: Add the rare earth metal in the refining stage. Stir the solution is uniformly by electromagnetic induction and inject it into the investment mold. After the mold is cooled, release the mold to obtain the casting mold.
  • Step 5: Heat treat and machine the target casting. The heat treatment process has a temperature of 800 ° C and a time of 2 h.

Adding titanium to improve the target performance

Raw materials: chromium and nickel with an elemental purity greater than 99.5%; silicon with an elemental purity greater than 99.9%; titanium with an elemental purity greater than 99.5%.

  • Step 1: Use a corundum-graphite-magnesia composite intermediate frequency vacuum induction furnace. Place the prepared materials in a corundum crucible and smelt them under a vacuum of 1×10-2 torr. The melting temperature is 1,500 to 1,550 ° C, the time 1 h, the power of the medium frequency induction furnace is 10~40kW, and the voltage and current of the induction coil are 100~400V and 200~380A respectively.
  • Step 2: Set a casting tube in the mold shell and extend the nozzle to the bottom surface of the mold shell. Then bake the mold shell to reach 650-700 ° C for casting. After that, cool the mold shell slowly to 850-800 ° C and kept the temperature for 1 h. Then cool it to the room temperature.

Target Bonding for NiCrSi Target

To increase the strength of the target, the NiCrSi target requires a copper plate to be soldered on the back side. The shape and size of the copper plate are the same as the target, and the thickness is 1~3mm. The target and the copper plate are welded firmly by indium bonding or elastomeric bonding, and the soldering temperature is 250 to 270 ° C for 4 hours.

Target Bonding
Target Bonding

Please visit https://www.sputtertargets.net/ for more information.

Thinning and Coating Process of Mobile Phone Cover Glass

According to the needs of various terminal applications, glass cover panels require various optical glass processing processes such as cutting, edging, drilling, polishing, thinning, chemical strengthening, printing, laser engraving and coating. Today we will introduce the thinning and coating of mobile phone cover glass, which are the most important parts of the whole manufacturing process.

Cover glass thinning process

The glass mentioned in this article is not the 3mm, 5mm, 8mm or even 10mm glass for civil use, but the cover glass for electronic products such as smartphones and tablet computers. Among the glasses currently on the market, the thinnest is 0.15 mm. There is a special thinning process that reduces the thickness of the glass.

Since Steve Jobs started using Corning Gorilla Glass for his iPhones, there emerges a new component for electronic products—cover glass. At the same time, the pursuit of thinner and lighter in the industry is also urging glass manufacturers to make changes to make thinner cover glass.

iPhone cover glass
iPhone cover glass

Currently, the thinnest glass of gorilla can be made 0.4mm, and the Asahi Glass can make 0.2mm glass. In general, people’s expectations for cover glass are nothing more than two:

1. Reduce the space occupied by the glass.

2. Make the glass cover a certain flexibility.

Mobile phone cover glass thinning process

There are not many processes for glass cover thinning: pre-cleaning—etching and thinning—–secondary cleaning——-grinding (single or double sided)—–post-cleaning—–check the package

Pre-cleaning: Remove the stain on the surface of the glass cover. It is one of the key steps affecting the effect of thinning.

Etching and thinning:  using acid and alkali to etch the glass cover achieve the purpose of thinning. The conditions and parameters (time, potash ratio, temperature, etc.) vary from manufacturer to manufacturer, which is the technical secret of the manufacturer.

Secondary cleaning: Clean the residue of the glass cover.

Grinding: To obtain a bright, flat surface. It is one of the key processes for appearance assurance and thickness tolerance control.

Post-cleaning: Clean the remaining grinding powder.

Check the packaging: The standard for the appearance of the glass is different depending on the requirements of the customer.

Mobile phone cover glass thinning treatment

1, multiple pieces of upright soak

2, waterfall flow processing

3, single piece vertical spray

Cover glass coating process

At present, vacuum magnetron sputtering coating technology is a widely used thin film deposition technology. The continuous development of sputtering technology and the exploration of new functional films have enabled the application of magnetron sputtering coating technology to be extended to many productions and scientific research fields.

magnetron sputtering system
magnetron-sputtering-system

magnetron sputtering coating applications

In the field of microelectronics, as a non-thermal coating technology, magnetron sputtering coating technology is mainly applied to materials that are not suitable for chemical vapor deposition or metal organic chemical vapor deposition. Moreover, using magnetron sputtering can obtain a large-area uniform film.

Magnetron sputtering technology is also used in optical films such as antireflection glass, low emissivity glass and transparent conductive glass. In the production of transparent conductive glass, the ITO conductive glass prepared by sputtering has an average transmittance of 90% or more in the visible light range.

In the modern machining industry, the use of magnetron sputtering technology to produce surface functional films, super hard films and self-lubricating films can effectively improve surface hardness, composite toughness, wear resistance and high temperature resistance and chemical stability, thus improve the service life of coated products.

In addition, magnetron sputtering coating technology also plays an important role in the research of high temperature superconducting thin films, ferroelectric thin films, giant magnetoresistive thin films, thin film luminescent materials, solar cells, and memory alloy thin films.

Magnetron sputtering coating advantages

Magnetron sputtering coating technology has become one of the main technologies of the industrial coating due to its remarkable advantages:

(1) Simple operation and easy control. In the coating process, if the sputtering conditions such as working pressure and electric power are relatively stable, the deposition rate is relatively stable.

(2) The deposition rate is high. When depositing most of the metal, especially the high melting point metal and oxide, such as tungsten, aluminum TiO2 and ZrO2 film, it has a high deposition rate.

(3) Low temperature of the substrate. Compared to two-pole sputtering or thermal evaporation, magnetron sputtering reduces the heating of the substrate, which is quite advantageous for achieving the sputter coating of the fabric.

(4) The sputtered film is strong. The sputtered film has excellent adhesion to the substrate and its mechanical strength is also improved.

(5) The sputtered film is dense and uniform. From the photomicrograph, the surface morphology of the sputtered film is fine and uniform.

(6)The sputtered films all have excellent properties. For example, sputtered metal films generally achieve good optical properties, electrical properties, and certain special properties.

(7) Easy to mass produce. The magnetron source can be expanded as required, so large-area coatings are achievable. In addition, sputtering can work continuously, and the coating process is easy to control automatically, so that the industrial assembly line can be realized.

(8) Environmentally friendly. Conventional wet plating produces waste liquid, waste residue, and exhaust gas, causing serious pollution to the environment. The magnetron sputtering coating method has high production efficiency while does not cause environmental pollution.

Please visit https://www.sputtertargets.net/ for more information.

How to make the phone case of gradient color like Huawei P20?

Gradient color is popular in 2018

It’s overwhelming how many smartphone models are currently available on the market today.  However, as for the color of the phone, what get are the same old black, white, silver and gray, in glossy or matte.

Well, recently an exciting new trend has emerged. The Huawei P20 series let people see the optimal color design and professional photography. A few months ago, Huawei launched the P20 in Twilight, and the dual-tone gradient inspired by the Aurora Borealis made people feel excited.

Huawei P20
Huawei P20

Before that, HTC also introduced the two-tone gradient scheme. Although it does not offer the popular Twilight color scheme, it does bring us a few appealing options with its latest flagship device.

HTC U11
HTC U11

Samsung has also jumped on board the gradient crazy. The Korean tech giant has unveiled a new version of its Galaxy A9 Star in China which features a sleek purple gradient.

Galaxy A9 Star2
Galaxy A9 Star2

Well, these are just a few examples to show that gradient color is the fashion of the year 2018. Are you curious about how to achieve this kind of gradient color? Is it difficult?

Film coating-Physical vapor deposition

Actually, all the color of the shell is about film coating. A cellphone is made from a variety of metals, with the most common being aluminum alloys, lightweight materials commonly found in the phone case. And the film coating is to apply a colored film on the phone case.

Physical vapor deposition is the most widely used film coating technology. Under vacuum conditions, the surface of the material (usually referred to as the sputtering targets or evaporating pellets) is vaporized into gaseous atoms by physical methods, and is then deposited on the surface of the substrate to form a thin film. The main methods of physical vapor deposition include vacuum evaporation, sputtering coating, plasma coating, ion plating, and molecular beam epitaxy.

How to coat the gradient color

PVD can coat gold, brass, rose gold, silver white, black, smoky, copper, brown, purple, blue, burgundy, bronze and other colors on stainless steel, copper, zinc alloy and other metals. There are many choices and the price is affordable, compared to pure gold or other pure metals. (PVD Coating Materials.pdf) You can refer to our previous article for more information: Introduction to PVD Coatings.

By controlling the parameters of different targets and thickness of the deposited film, the film exhibits different colors (the gradation colors mentioned above) under the reflection, refraction and interference of light. Specifically, in the plating furnace space, bombard a specific sputtering target with ultra-high speed electrons; use a certain mask to cover a part of the ion cloud so that only the other part of the ion cloud can be attached to the substrate and forms a very thin layer of nano-plating; control the thickness of the coating to form a nanometer thickness difference; then spray the background color.

For more information, please visit https://www.sputtertargets.net/.

Introduction to PVD Coatings

What is PVD coating technology

PVD, or physical vapor deposition, is an advanced surface treatment technology widely used in the world. Under a vacuum condition, utilize the gas discharge to separate the gas or the evaporated substance, then accelerate the gas ion or the evaporated atoms to bombard the substrate and deposit a film. PVD film has fast deposition speed as well as strong adhesion, good diffraction, and wide application range.

PVD coating colors

PVD can coat gold, brass, rose gold, silver white, black, smoky, copper, brown, purple, blue, burgundy, bronze and other colors on stainless steel, copper, zinc alloy and other metals. There are many choices and the price is affordable, compared to pure gold or other pure metals. (PVD Coating Materials.pdf)

PVD Coating Materials and Their Characteristics
PVD Coating Materials and Their Characteristics

Applications

PVD technology is widely used in the processing of door and window hardware, lamps, jewelry, handicrafts, and other decorative products.

PVD is now quite popular in the hardware field, and many of the world’s leading hardware manufacturers have begun to develop PVD products and mass production.

PVD for molds and precision parts

In recent years, PVD coating technology has been applied more and more in the work surface strengthening treatment of molds. Its outstanding advantages are that it can effectively improve the service life of the mold, and at the same time reduce the coating temperature to about 250 °C ~ 500 °C, which can reduce the deformation of the workpiece. The PVD composite coating has excellent performance and has potential applications that cannot be underestimated. One of the main applications of PVD technology in the mold industry is TiN coating.

PVD & CVD

There are currently two coating methods commonly used in production: physical vapor deposition (PVD) and chemical vapor deposition (CVD). The former has a deposition temperature of 500 ° C and a coating thickness of 2 to 5 μm; the latter has a deposition temperature of 900 ° C to 1100 ° C, a coating thickness of 5 to 10 μm, and the device is simple and the film is uniform.

Previously, most cemented carbides are coated by CVD. However, since the deposition temperature is high, the cemented carbide coated by the CVD method,  a brittle decarburization layer (η phase) is easily formed between the coating layer and the substrate, resulting in brittle fracture of the blade. In the past decade or so, with the advancement of coating technology, the cemented carbide can also adopt the PVD method.

Development of cemented carbide coatings

Coating refers to the application of a thin layer of wear-resistant, refractory metal or non-metallic compound on the substrate of cemented carbide or high-speed steel by vacuum evaporation and sputtering.

A good coating material is required to have high hardness, good wear resistance, stable chemical properties, no chemical reaction with the workpiece material, heat and oxidation resistance, low friction factor, and strong adhesion to the substrate. However, a single coating material is difficult to meet the above requirements. Therefore, the development of cemented carbide coating materials has entered a new stage of thick film, composite film and multi-component coating.

The most mature and widely used cemented carbide coating material is TiN, but the bonding strength of TiN and the substrate is less than that of TiC. TiC coatings have high hardness and wear resistance, and good oxidation resistance, but they are brittle and not resistant to impact. Both of these kinds of coatings have advantages and disadvantages, and TiCN combines their merits.

TiCN coating
TiCN coating

Combine 1)the newly developed multi-component, ultra-thin TiCN, TiAlN coating, 2)TiC, TiN, Al2O3 coatings, and 3)a new anti-plastic deformation matrix can significantly improve the toughness, bond strength of the coating to the substrate, and wear resistance of the coating. At present, the technology of coating diamond film on the cemented carbide substrate is successfully realized, and the performance of the tool is comprehensively improved.

TiAlN, CrN, and TiAlCrN are also new materials for cemented carbide coatings developed in recent years. The chemical stability and oxidation resistance of TiAlN are good. Compared with TiN, the tool life can be improved by 3 to 4 times when processing high alloy steel, stainless steel, titanium alloy and nickel alloy with TiAlN.

CrN is a titanium-free coating with good chemical stability and no sticking. It is suitable for cutting titanium and titanium alloys, copper, aluminum and other soft materials.

TiAlCrN is a gradient structure coating, which not only has high toughness and hardness, but also has a small friction factor. It is suitable for milling cutters, hobs, taps and other tools, and its cutting performance is obviously better than TiN.

In addition to the above new coatings, there are some coatings with specific functions, such as MoS2, DLC lubricated coatings, which have a small friction factor (0.05) and are suitable for coating tools such as taps and drills to improve chip evacuation performance.

For more information, please visit https://www.sputtertargets.net/.

Year in Review: 2018 Top Posts Collection

Happy New Year in 2019! We are very happy with your company and encouragement that push us to insist on updating every week. On the occasion of the arrival of 2019, let us summarize the Top Posts in 2018 for you.

Metal History

“Metal History” is a popular column we have opened this year, aiming at introducing the discovery of different kinds of metals. Among them, the Top 3 posts in this column are as follows:

How was titanium discovered? | History of Titanium

Titanium is a metal element that is known as “space metal” because of its light weight, high strength and good corrosion resistance. The most common compound of titanium is titanium dioxide, and other compounds include titanium tetrachloride and titanium trichloride. Click the title of the article to know more.

Discovery and development of tungsten | History of Tungsten

The history of tungsten dates back to the 17th century. At that time, miners in the Erzgebirge Mountains of Saxony, Germany, noticed that some of the ore would interfere with the reduction of cassiterite and produce slag. The miners gave the mines some German nicknames: “wolfert” and “wolfrahm”. Click the title of the article to know more.

How was cerium discovered? | History of Cerium

Cerium is the most abundant rare earth elements. It is a silvery gray active metal, whose powder is easily oxidized in the air and soluble in acid. Cerium has been widely used in the automotive industry as a catalyst to reduce emission, and in glass industry as glass polishing materials. Cerium sputtering target is an important material in optical coating. Click the title of the article to know more. Click the title of the article to know more.

Metal Materials Application

Apart from history, we also introduce the multiple applications of these metal materials. Among them, the Top 3 posts in this column are as follows:

Molybdenum Target Mammography Detection

At present, molybdenum target mammography is considered the recommended breast screening examinations for women’s breast cancer, one of the major causes of deaths among women, affects about 12% of women around the world. Click the title of the article to know more.

Application of titanium and titanium alloys in medical field

Titanium is an ideal medical metal material and can be used as an implant for the human body. Titanium alloy has been widely used in the medical field and has become the material of choice for medical products. Click the title of the article to know more.

A short analysis of sputtering targets for semiconductor application

Semiconductors have high requirements for the quality and purity of the sputtering materials, which explains why the price of anelva targets is relatively high. Click the title of the article to know more.

Sputtering Targets

Sputtering Target is the consistent keyword of our website, and thus we have shared many useful information about some specific type of sputtering targets. Our intention is to help you better understand these materials—their properties, applications, developing prospect and so on. And the followings are the posts you really have to read. Among them, the Top 3 posts in this column are as follows:

PVD vs. CVD: What’s the difference?

In recent years, physical vapor deposition (PVD) and chemical vapor deposition (PVD) have wide applications in various industries to increase the hardness of tools and molds or apply beautiful colors to the products. Thus these two methods are considered as the most attractive surface coating technologies. Click the title of the article to know more.

What is the Indium Bonding for Sputtering Target?

The term “indium bonding” in thin film coating industry, simply speaking, refers to bond two (or more) sputtering targets with indium (In), or one (or more) with indium plate together. Click the title of the article to know more.

What is Target Poisoning in Sputtering Deposition?

At some stage in the sputtering deposition, positive ions are continuously amassed on the surface of the sputtering target. Due to the fact that those fantastic ions aren’t neutralized, the negative bias of the target surface gradually decreases, and progressively the normal operation can not be completed. This is the target poisoning phenomenon. Click the title of the article to know more.

Glad you are part of SAM’s 2018. Next year, please continue following us and we promise to give you more valuable information! Also, you can visit our official website https://www.sputtertargets.net/ for more information.