Lithium Cobalt Oxide (LiCoO2) Sputtering Targets
Purity: 99.9%, Size: 2”, Thickness: 0.125”
Sputtering is a proven technology capable of depositing thin films from a wide variety of materials onto diverse substrate shapes and sizes.
The process using sputter targets is repeatable and can be scaled up from small research and development projects. The process with sputter targets can be adapted to production batches involving medium to large substrate areas. The chemical reaction can occur on the target surface, in-flight, or on the substrate depending on the process parameters. The many variables make sputter deposition a complex process but give experts a significant degree of control over the growth and microstructure of the deposited area.
Applications of Sputtering Targets
Sputtering targets are used for film deposition. The deposition made by sputter targets is a method of depositing thin films by sputtering that involves eroding material from a “target” source onto a “substrate,” such as a silicon wafer.
Semiconductor sputtering targets are used to etch the target. Sputter etching is chosen in cases where a high degree of etching anisotropy is required and selectivity is not a concern.
Sputter targets are also used for analysis by etching away the target material. One example occurs in secondary ion spectroscopy (SIMS), where the target sample is sputtered at a constant rate. As the target is sputtered, the concentration and identity of sputtered atoms are measured using mass spectrometry. With the help of the sputtering target, the composition of the target material can be determined, and even extremely low concentrations of impurities can be detected.
Sputtering targets also have application areas in space. Sputtering is one of the forms of space weathering, a process that changes the physical and chemical properties of airless bodies such as asteroids and the Moon.
Lithium cobalt oxide is a chemical compound with the formula LiCoO2. Lithium cobalt oxide is a dark blue or bluish-gray crystalline solid commonly used in the positive electrodes of lithium-ion batteries.
Now let’s examine how lithium cobalt oxide sputtering targets can be used in batteries. Batteries with very small sizes are of great interest as the sizes of portable microelectronic devices and sensors continue to decrease. Thin film batteries can be used as power sources for various low-power electronic devices such as portable electronics and micro electro mechanical systems (MEMS), which require very low power and current levels and can therefore be powered by thin film batteries.
In battery applications, a magnetron sputter system can be used. The required thin film lithium can generally be deposited by conventional sputtering target techniques, whereby a LiCoO2 sputtering target assembly—defined as the LiCoO2 sputtering target bonded to a backing plate—can be used to deposit the required thin film lithium. For producing Li thin films, a D.C. (direct current) magnetron sputter system can be employed. The LixCoyO2 sputtering target is represented by the formula LiCoO2 and forms part of a cathode assembly that, together with an anode, is placed in an evacuated chamber filled with an inert gas, preferably argon. Magnets are positioned above the LiCoO2 sputtering target, and a switch connects the target backing plate to a D.C. voltage source. A substrate support is located below the LiCoO2 sputter target within the chamber.
During operation, a high-voltage electrical field is applied across the cathode and the anode. The inert gas is ionized by collisions with electrons ejected from the cathode. Positively charged gas ions are attracted to the cathode and, upon striking the target surface, dislodge target material. The dislodged material travels through the evacuated chamber and deposits as a LiCoO2 thin film on the desired substrate, which is typically positioned close to the anode.
