High purity metal sputtering target application field

High purity sputtering target applications mainly include semiconductor, panel, photovoltaic and optical devices. Integrated circuits, flat panel display, solar cells, information storage, tool modification, optical devices, high-grade decorative products and other production processes need to carry out sputtering coating process, sputtering target application field is very broad. For the large target material consumption of the industry mainly integrated circuit, flat panel display, solar cells, magnetic recording media, optical devices, etc.. Among them, high purity sputtering target is mainly used in the field of higher material purity and stability requirements, such as integrated circuits, flat panel displays, solar cells, magnetic recording media, intelligent glass and other industries.

Semiconductor chips have high technical requirements for sputtering targets, and the price is also extremely expensive. The purity and technology requirements of the target are higher than those of flat displays, solar cells and other applications. Semiconductor chips for sputtering target material purity metal materials, internal microstructure set a strict standard, sputtering target materials if too high content of impurities, forming film will not be able to achieve using the required performance, and in the sputtering process in particles is formed on the wafer, or damage, cause a short circuit will seriously affect the performance of the film. Generally speaking, the chip manufacturing of sputtering target metal purity requirements are the highest, usually 99.9995% (5N5) above, flat panel display, solar cells are required to reach 99.999% (5N), 99.995% (4N5) above.

Semiconductor target: used for fabrication of wafer conductive barrier layer and packaging metal wiring layer

In the wafer manufacturing and chip packaging two major links need to be used for sputtering target, which in the wafer manufacturing link, the target is mainly used to attach the wafer conductive layer, barrier layer and metal gate, and in the chip packaging link, the target is used to generate the metal layer under the convex point, wiring layer and other metal materials. According to SEMI statistics, the cost of target accounts for about 3%. However, the quality of sputtering target directly affects the uniformity and performance of conductive layer and barrier layer, thus affecting the transmission speed and stability of chip. Therefore, target material is one of the core raw materials in semiconductor production.

In the wafer making process, the sputtering target material for semiconductor is mainly used for the fabrication of the conductive layer and barrier layer of the wafer and the metal gate, mainly using aluminum, titanium, copper, tantalum and other metals. The metal target material for chip packaging is similar to the wafer making, mainly including copper, aluminum, titanium and so on. Among them, the wafer production of conductive layer using a metal target materials mainly include the aluminum target, the target and copper barrier layer using metal target mainly include tantalum target material and titanium target, blocking layer has two main functions, on the one hand is cut off and insulation, prevent spread of conductive metal layer to the silicon wafer body materials, on the other hand as a stick, used for bonding of metal and silicon material. In general, more than 110 nm technology node wafer with aluminum and titanium as a conductor and barrier layer of thin film materials, below 110 nm wafers using copper, tantalum materials as the conductor and the barrier layer of thin film materials, with the narrowing of the wafer process, the future of copper target, tantalum target and making metal grid with the dosage of the titanium target proportion will continue to improve.

Panel target material: mainly used for ITO glass and touch screen electrode

In the flat panel display industry, target sputtering coating is mainly used in the production of display panel and touch screen panel, which is mainly used to make ITO glass and touch screen electrode. Indium tin oxide (ITO) target is the most used, followed by molybdenum, aluminum, silicon and other metal targets.1) In the production process of flat display panel, the glass substrate shall be formed into ITO glass by sputtering coating for many times, and then processed and assembled for LCD panel, PDP panel and OLED panel;2) For the production of touch screen, ITO glass needs to be processed, coated to form electrode, and then assembled and processed with protective screen and other components. The silicon dioxide film formed by sputtering silicon target mainly increases the adhesion and smoothness of glass and ITO film, passivation and protection of the surface, and the etching of MoAlMo target mainly plays the role of metal lead bridging. In addition, in order to realize the anti-reflection, extinction and other functions of flat panel display products, you can also add the corresponding coating layer in the coating process.

Photovoltaic target: Backcharge level used to form solar thin film cells

Target material is mainly used to generate the back electrode of solar thin film cell, crystal silicon solar cell seldom use sputtering target material. Solar cells mainly include crystalline silicon solar cells and thin film solar cells. Crystalline silicon solar cells have high conversion efficiency, stable performance, and mature industrial links, and occupy the dominant position in the solar cell market. According to different production processes, crystalline silicon solar cells can be divided into silicon wafer coated solar cells and PVD process high conversion silicon wafer solar cells. Among them, the production of silicon wafer coated solar cells does not use sputtering targets, which are mainly used in the field of solar thin film cells.

The back charge level of solar thin film cell formed by sputtering coating of target material has three main purposes: first, it is the negative pole of each single cell; Second, it is the respective battery series conductive channel; Third, it can increase the reflection of light from solar cells. The sputtering target used for solar thin film cells is mainly square plate, which has higher purity requirements than the target used for semiconductor chips, generally above 99.99%.At present, the sputtering targets commonly used in preparing solar cells include aluminum target, copper target, molybdenum target, chromium target, ITO target, AZO target (alumina and zinc) and so on. Among them, aluminum target and copper target are used for conductive layer film, molybdenum target and chromium target are used for barrier layer film, ITO target and AZO target are used for transparent conductive layer film.

Optical device target: the use of optical coating to change the light wave transmission characteristics

Optical devices rely on optical coating to form a layer or multilayer dielectric film and metal film, through the film system composed of the two to change the characteristics of light wave transmission, including transmission, reflection, absorption, scattering, polarization and phase change of light, mainly used in silicon, niobium, silicon dioxide, tantalum and other targets. Optical devices are widely used, mainly including smart phones, car lenses, security monitoring equipment, digital cameras, CD players, projectors, etc.High-end applications include aerospace surveillance lenses, biometrics, DNA sequencing research equipment in the life sciences, medical examination instrument lenses, semiconductor testing equipment, as well as large field of view projection lenses (such as IMAX), 3D printers and other equipment required optical components and lenses.