Vacuum Coating by Sputtering

Vacuum coating by sputtering has established a leading position for the deposition of thin films because of its relatively easy scalability to high volumes and sizes, its good control of most layer characteristics, and its wide variety of available materials and possible coating stacks. The technology is commonly accepted and widely used in the architectural and automotive industries. In display and PV applications, however, the use of rotatable technology has been introduced more recently.

Within the large area coating business, the rotating cylindrical magnetron concept has proven to offer superior properties relative to the planar concept and to satisfy most industrial requirements. The geometry and sputter performance of rotating cylindrical sputter targets result in several advantages relative to planar sputter targets. Read More

What are Sputtering Targets?

A sputtering target is a material that is used to create thin films in a technique known as sputter deposition, or thin film deposition. During this process the sputtering target material, which begins as a solid, is broken up by gaseous ions into tiny particles that form a spray and coat another material, which is known as the substrate. Sputter deposition is commonly involved in the creation of semiconductors and computer chips. As a result, most sputtering target materials are metallic elements or alloys, although there are some ceramic targets available that create hardened thin coatings for various tools.

Depending on the nature of the thin film being created, sputtering targets can very greatly in size and shape. The smallest targets can be less than one inch (2.5 cm) in diameter, while the largest rectangular targets reach well over one yard (0.9 m) in length. Some sputtering equipment will require a larger sputtering target and in these cases, manufacturers will create segmented targets that are connected by special joints.

The designs of sputtering systems, the machines that conduct the thin film deposition process, have become much more varied and specific. Accordingly, target shape and structure has begun to widen in variety as well. The shape of a sputtering target is usually either rectangular or circular, but many target suppliers can create additional special shapes upon request. Certain sputtering systems require a rotating target to provide a more precise, even thin film. These targets are shaped like long cylinders, and offer additional benefits including faster deposition speeds, less heat damage, and increased surface area, which leads to greater overall utility.

The effectiveness of sputtering target materials depends on several factors, including their composition and the type of ions used to break them down. Thin films that require pure metals for the target material will usually have more structural integrity if the target is as pure as possible. The ions used to bombard the sputtering target are also important for producing a decent quality thin film. Generally, argon is the primary gas chosen to ionize and initiate the sputtering process, but for targets that have lighter or heavier molecules a different noble gas, such as neon for lighter molecules, or krypton for heavier molecules, is more effective. It is important for the atomic weight of the gas ions to be similar to that of the sputtering target molecules to optimize the transfer of energy and momentum, thereby optimizing the evenness of the thin film. Read More

Functional Thin Films and Sputtering Target Materials

Sputtering targets provide thin-film materials deposited by the sputtering method. Kobelco Research Institute, Inc. started the target material business in 1993 and its competitive strength exists in the approach of originally developing high- performance film-materials before providing the target-materials required to make the films. The research and development group of Kobe Steel is responsible for the development of original thin- films and has contributed to the steady growth of the business in cooperation with the Kobelco Research Institute, Inc. This article summarizes the developments, current statuses and futures of Al- Nd and Ag-Nd-Cu alloys, which have found lucrative applications in LCD panels and optical storage media respectively. Also described is the spray-forming process used in the production of Al-Nd alloy targets. Read More

Metal Targets during Sputtering

When a Cu surface is sputtered by ion bombardment under the condition that Mo atoms arrive at the Cu surface during sputtering an unexpected phenomenon can arise: the surface of the Cu target becomes covered with microscopic cones. The cone density increases with increasing flux density of arriving Mo atoms. When the cones are closely spaced they give the target a velvet-like black appearance. The result of dense cone coverage are a lower sputtering yield and a more oblique ejection of sputtered material. The cone tops seem to consist of Mo nuclei which are constantly replenished via surface migration and protect the underlying Cu from being sputtered. Read More

Alloy Sputtering Target

A sputtering target of platinum-cobalt alloy is disclosed which contains 10 to 55% by weight of platinum; 1 to 15% by weight of a first additional element selected from the group consisting of nickel and tantalum; no more than 1.5% by weight of a second additional element selected from the group consisting of boron, titanium, lanthanum, cerium, neodymium, beryllium, calcium, zirconium, and silicon; no more than 20% by weight of chromium; and balance cobalt. A method for manufacturing the sputtering target is also disclosed. In the method, a platinum-cobalt alloy containing specific ingredients in predetermined amounts is first prepared. Then, the platinum-cobalt alloy is subjected to hot plastic working with a thickness reduction of no less than 30%. Subsequently, the alloy thus hot worked is subjected to a cold plastic working with a thickness reduction of no less than 5% at a temperature less than the recrystallization temperature of the alloy. Read More

Composite Sputtering Target Structures

A target structure is provided for use in a magnetically enhanced diode sputter coating source having a sputtering target which at end-of-life has an eroded surface with a known shape.

The sputtering target has a non-sputtered profiled back surface conforming substantially in shape to the eroded surface at end-of-life.

A backing plate is bonded to the sputtering target which has a bonding surface complementary to the non-sputtered back surface of the sputtering target and is designed to mate therewith.

A method is provided for fabricating the target structure and bonding the sputtering target to the backing plate by isostatic pressing. Read More

Superhard Thin Film Coatings

As a result of increased requirements for abrasion resistant and protective thin film coatings, the hardness of thin film coatings has been steadily increasing over the past decade, due primarily to new materials, improved deposition processes and use of nanostructures and nanocomposites. Because it would not be possible to address all these materials, we will briefly describe the following broad categories, with emphasis on nanostructured thin films:

Binary thin films, including transition metal based materials, chromium-based materials, boron-based materials, carbon and diamond-based materials, tungsten and molybdenum based materials.
Ternary thin film materials
Quaternary and higher component thin film materials
Nanostructured materials
Wear resistant thin films are deposited by a wide variety of processes, but most often by physical vapor deposition (PVD) and chemical vapor deposition (CVD) techniques because they can be scaled up to industrial sizes and quantities. Read More

Electron Beam Gun Crucibles & Thin Film Deposition

Electron beam evaporation is a method of thin film deposition involving the use of an electron beam source, or electron beam gun (EB gun).

Both names are commonly used, but the actual device consists of a heated cathode emitting a high flux of electrons which are accelerated by high voltage and focussed into a water cooled hearth by a magnetic system.

The material to be evaporated (the evaporant) is placed in a crucible within the hearth where it is heated to vaporization which then deposits on the substrate to form the required thin film.

The electron beam evaporation technique enables very high temperatures to be obtained, allowing fast deposition rates and a wide range of materials to be evaporated.

The technique is controllable, repeatable and compatible with the use of an ion source to enhance the resultant thin film performance characteristics.

Thin Film Deposition

Thin film deposition processes play a critical role in the production of high-density, high-performance microelectronic products.

Considerable progress has been achieved in the development of deposition processes — and in the development of the reactor systems in which they are carried out.

This report discusses the technology trends, products, applications, and suppliers of materials and equipment.

It also gives insights to suppliers for future user needs and should assist them in long range planning, new product development and product improvement.

This report compares some of the issues impacting users of different deposition tools, including: APCVD (SACVD), LPCVD, PECVD, HDPCVD, ALCVD, PVD, ALD. Read More

Thin Film Deposition Materials

Thin film material are widely used in various industries for one or more applications. They are used in the encapsulation of photovoltaic solar cell, semiconductor and electrical industry for miniaturization of circuit boards. Their major application is in photovoltaic solar cells, which accounts for a majority of their usage, followed by the MEMS, electrical, semiconductor, and optical coating industry.

The thin film material market has a significant number of small as well as few big manufacturers. The companies in thin film material market are segmented according to the technology used by them. In the thin film material market, the companies are sometimes restricted to specific technology because of their geographical presence. For instance First Solar (U.S.) has a market share of around 90% in CdTe technology and it has majority of market share only in North America as the usage of cadmium in Europe is highly regulated. Hanergy has one third of the market share of CIS/CIGS technology and a majority of its share is in the Asia-Pacific and European market.

The thin film material market has no specific set of raw material or ingredients. Every thin film is unique and the manufacturers use their own set of raw material and ingredients to manufacture these material. The industry also lacks the need for bulk suppliers. The raw material that are used in bulk are rare material and chemicals such as cadmium, indium, telluride, and certain common metals such as copper. These material are not difficult to source, unless there is some crisis or regulatory problems that prohibit their usage beyond a certain value. Read More