If you are looking for high-quality products, please feel free to contact us and send an inquiry, email: email@example.com
The silicide process has been an essential part of semiconductor manufacturing since the early 1980s. It was first developed to reduce contact resistance between tungsten contacts and the source-drain regions or the gate electrode of transistors. This reduction was important to enable higher drive currents and enhance device performance.
Silicides have metal-like properties and are formed by reacting silicon with refractory or near-noble metals. Many of the elements in the periodic table can form silicides with silicon, but the most common ones used in semiconductor fabrication are titanium silicide, tungsten silicide, cobalt silicide and nickel silicide. Silicides can be made as a thin film, or in bulk form. The most commonly used silicides in the industry are TiSi2, WSi2, TaSi2 and CrSi2.
A significant challenge for future microelectronics devices is to increase the number of transistors on a single chip, while maintaining a reasonable power consumption. A key technology for achieving this goal is multi-level interconnections (MLI) that provide electrical connectivity between the different layers of the device.
The MLI process involves depositing a refractory or noble metal on the exposed surface of silicon and then annealing it in a non-oxidizing atmosphere to convert it to silicide. This annealing is usually done in several stages, which allows the formation of various phases of silicide. In the case of titanium, for example, it can be converted to high-resistance C49 phase or low-resistance C54 phase silicide. The latter is typically used in CMOS processes for ohmic contacts of the source, drain and poly-Si gate.