How does static electricity come from in the electronics industry?
Although static electricity can not cause great harm to the human body like electricity, its damage to electronic products is not small. Many electronic processing companies are very troubled by static electricity, which has led many well-known enterprises to invest a lot of money in anti-static improvement of production workshops. Conduct static protection training for employees. So how does static electricity come from in the electronics industry?
(1) Contact-separation electrification - when two objects are in contact, and the distance between them is less than 25×10-8cm, the electrons of different atoms are different in energy level due to the different ability of electrons to get electrons from different atoms. . Therefore, two layers of equal-sized and opposite polarity appear on both sides of the interface. These two layers of electric charge are called electric double layers, and the potential difference between them is called the contact potential difference. According to the theory of the electric double layer and the contact potential difference, it can be inferred that when two substances are in close contact and then separated, static electricity may be generated.
Electrostatic sequence - according to the polarity of the electric double layer between the two substances, the positively charged ones are in front and the negatively charged ones are arranged in the back, which can be arranged in a long sequence. The sequence is called an electrostatic sequence or an electrostatic charging sequence.
(2) Breaking electrification - After the material is broken, it can cause the separation of positive and negative charges in the macroscopic range, that is, the generation of static electricity, which is called breaking electrification. The electrification of the solid pulverization and liquid separation process is a breaking electrification.
(3) Inductive electrification - charged body A is negatively charged, and conductor B is nearby.
Under the electrostatic induction of charged body A, a positive charge appears at the end of B;
Since the conductor B is connected to the ground conductor C, the ground potential of B is still zero;
When B leaves the ground conductor C, B becomes a charged body.
(4) Charge transfer - When a charged body is in contact with an uncharged body, the charge is redistributed, that is, charge transfer occurs to charge the uncharged body.
When charged droplets or dust impinge on the conductor, charge migration occurs; when gas ions are emitted on an uncharged object, charge migration also occurs.