Basic Definition and Chemical Nature of Silanes
Silanes are a class of inorganic compounds formed by the direct bonding of silicon (Si) and hydrogen (H), with the general chemical formula SinH₂ₙ₊₂ (n≥1). Their core characteristic lies in the covalent bonding of silicon atoms to hydrogen atoms, forming chain or cyclic structures. In actual industry, silane (SiH₄) is the most widely used and is often simply referred to as "silane." However, strictly speaking, the silane family includes more than ten members, such as silane, disilane (Si₂H₆), and propane (Si₃H₈). For example, disilane is gradually replacing silane in some applications in advanced semiconductor manufacturing processes due to its lower film-forming temperature and faster deposition rate.

Classification and Properties of Silanes
Based on molecular structure and applications, silanes can be divided into two main categories:
* **Basic Silanes (Pure Silicon Hydrogen Compounds)**
* **Silane (SiH₄):** Colorless gas, melting point -185℃, boiling point -112℃. It is easily ignited in air, releasing a large amount of heat. Its purity is divided into industrial grade (3N-4N) and electronic grade (6N and above). The latter is used in semiconductor CVD processes, and purity directly affects chip performance.
* **Silane (Si₂H₆):** Higher silicon content, resulting in 30% higher film density and a 50℃ lower deposition temperature. Suitable for high-end logic chip manufacturing.
* **Advanced Silanes (e.g., Si₃H₈, Si₄H₁₀):** Stability decreases with increasing molecular weight. Requires low-temperature storage and is mainly used in the synthesis of special materials.
Functional Silanes (Derivative Compounds)
Silane Coupling Agents: Such as γ-aminopropyltriethoxysilane (KH-550), which enhances interfacial adhesion by introducing functional groups such as amino and epoxy groups, and are widely used in rubber, coatings, and composite materials.
Silane Crosslinking Agents: Used in the vulcanization of silicone rubber to improve the material's temperature resistance and mechanical strength, and are core raw materials for automotive seals and wires and cables.

Industry Status and Application Extensions
Silanes, as "flowing pure silicon," are a strategic resource for industries such as microelectronics, photovoltaics, and display panels. For example, TOPCon photovoltaic cells require 24 tons of silane per GW of capacity, a 50% increase compared to PERC technology; in silicon-based anode materials, 0.6 tons of silane are required per ton of silicon-carbon anode masterbatch, driving lithium battery energy density to exceed 300Wh/kg. With the accelerated localization of semiconductors and the explosive growth in new energy demand, silanes are penetrating from traditional chemical fields to high-end manufacturing.