Properties and characteristics of nitric oxide and its application in semiconductor technology

Nitric oxide is an inorganic Compound with the chemical formula NO. It is a nitrogen oxide. It is a colorless gas at room temperature and pressure. It is slightly soluble in water, soluble in ethanol and carbon disulfide, and has the following detailed properties:

1. Chemical properties of nitric oxide

Nitric oxide is a reducing gas that reacts with oxygen to form nitrogen dioxide (NO₂). Nitric oxide can also react with a variety of compounds to form different oxides of nitrogen. Under high temperature conditions, it can also react with hydrogen to produce ammonia (NH3). In addition, when an oxidant is present, nitric oxide can be oxidized to NO₂ or other nitrogen oxides.

2. Physical properties of nitric oxide

Nitric oxide is a colorless gas at room temperature with a slightly sweet smell. Its molecular weight is about 30.01 g/mol, its solubility in water is low, and it can form trace amounts of nitrous acid (HNO₂). Its boiling point is about −151.2°C and its melting point is about −163.6°C. In addition, the density of nitric oxide is about 1.34 g/L (under standard conditions), which is slightly lighter than air.

3. Biological properties of nitric oxide

Nitric oxide is an important signaling molecule in the body, involved in regulating vasodilation, nerve conduction and immune response, and has an important influence on processes such as blood flow regulation, inflammatory response and cell death.

Application of Nitric Oxide in Semiconductor technology：

1. Vapor Deposition

Nitric oxide can be used as a nitrogen source in vapor deposition for the preparation of nitride films such as gallium nitride (GaN) and silicon nitride (Si₃N₄).

2. Doping process

In some cases, nitric oxide can be used for doping, especially in nitrogen doping processes, to improve the conductivity of semiconductor materials.

3. Etching process

Nitric oxide can be mixed with fluoride gases to aid in the removal of material during dry etching, particularly during the etching of silicon oxides.

4. Oxidation reaction

Nitric oxide acts as an oxidant during the oxidation process, promoting the uniformity and quality of film growth.

5. Cleaning and handling

Nitric oxide can be used to remove surface contaminants and improve the purity of semiconductor materials.