Principle of Ethereum plasma

1. Originally, I came to search for the answer to this question. I just read the introction of others. I'll borrow flowers and offer them to Buddha<
1.
plasma
cleaning principle:
clean the chamber at low pressure (using vacuum pump to pump air), inject Ar gas, and then add high voltage to the electrode in the chamber to ionize the gas in the inverted chamber. Due to the existence of electric field, the positive ions live in the negative electrode, and the negative electrons run to the positive electrode, It will also impact the gas molecules in the chamber, forming a chain reaction. In the process of running to the negative electrode, Ar + ions will impact on the surface of the object to be cleaned, and react with the surface stains or foreign matter molecules to achieve the cleaning effect. Then vacuum pump is used to remove the dirty Ar gas in the chamber, so as to cycle
2.
ar
function
generally, plasma uses O2
or ar
as cleaning gas. As AR is an inert gas, it is not easy to react with other objects. Therefore, in general, plasma uses AR, except for some special requirements.

2. Plasma is a form of matter, which is mainly composed of free electrons and charged ions. It widely exists in the universe and is often regarded as the fourth state of matter, which is called plasma state or "super gas state". Plasma has high conctivity and strong coupling with electromagnetic field. Plasma was discovered by crooks in 1879. In 1928, American scientists Irving Langmuir and Tonks first introced the term "plasma" into physics to describe the state of matter in gas discharge tubes< The principle of plasma is generally regarded as the fourth form of matter except solid state, liquid state and gas state. If the gas is heated continuously, the molecules are decomposed into atoms and ionized, the gas composed of ions, electrons and neutral particles is formed, which is called plasma. The properties of plasma and gas are very different. The long-range Coulomb force plays a leading role in the plasma, and the electron mass is very small and can move freely. Therefore, there are significant collective processes in the plasma, such as oscillation and wave behavior. There are acoustic waves in plasma, which are independent of electromagnetic radiation< Plasma is the most widespread state of matter in the universe. At present, 99% of the observed cosmic matter is plasma, although the distribution range is very thin

artificial plasma:
* ionized gas in fluorescent lamp and neon lamp tube
* high temperature ionized gas in nuclear fusion experiment
* high temperature arc generated ring electric welding, Arc in arc lamp
* gas from rocket
* plasma display and TV
* plasma proced in front of thermal shield layer of spacecraft when spacecraft returns to earth
* plasma used to etch dielectric layer in proction of integrated circuit
* plasmon sphere

plasma on earth:
* St. Elmo & # 39; s fire
* Sprites, elves, Jets
* flame (upper part of high temperature)
* lightning
* low temperature plasma NTP
* globular lightning
* ionosphere in atmosphere
* Aurora

plasma in space and Astrophysics:
* sun and other stars (in which plasma is proced by thermonuclear fusion)
* solar wind < B R / > * interplanetary medium (exists between planets)
* interplanetary medium (exists between stars)
* intergalactic medium (exists between galaxies)
* IO - flux tube of Jupiter
* accretion disk
* Nebula
- properties of plasma

plasma state Often known as "super gas", it has many similarities with gas, such as: there is no definite shape and volume, and it has fluidity, but plasma also has many unique properties

ionization:
the biggest difference between plasma and ordinary gas is that it is an ionized gas. Due to the existence of negatively charged free electrons and positively charged ions, they have high conctivity and strong coupling with electromagnetic field: charged particles can be coupled with electric field, and charged particle flow can be coupled with magnetic field. Electrodynamics is used to describe plasma, and a theory called magnetohydrodynamics has been developed<

constituent particles:
unlike ordinary gases, plasma contains two or three different constituent particles: free electrons, positively charged ions and non ionized atoms. This allows us to define different temperatures for different components: electron temperature and ion temperature. The plasma with mild ionization is called "low temperature plasma". Highly ionized plasma, with high temperature of ions and electrons, is called "high temperature plasma"

compared with the general gas, the interaction between plasma particles is much larger

velocity distribution:
the velocity distribution of general gases satisfies the Maxwell distribution, but the plasma may deviate from the Maxwell distribution e to the coupling with the electric field< Plasma physics is a branch of physics that studies the properties of plasma. Plasma is the fourth state of matter, which is a mixture of charged particles and neutral particles, such as electrons and ions. It is quasi neutral in macroscopic view, that is, the number of positive and negative ions is basically equal, and it is electrically neutral as a whole, but it has obvious electromagnetic properties in small scale. The interaction between the band point particles is long-range Coulomb interaction. The motion of a single band point particle is affected by many other charged particles, which can also proce electromagnetic fields and affect the motion of other particles. The purpose of plasma physics is to study some basic processes in plasma, including the motion of plasma, the wave phenomenon in plasma, the equilibrium and stability of plasma, the collision and transport process, etc. Plasma physics has broad application prospects, including controlled nuclear fusion, space plasma, plasma astrophysics, low temperature plasma and so on

there are three common research methods in plasma physics: single particle orbital theory, magnetohydrodynamics and kinetic theory. The single particle orbital theory does not consider the effect of charged particles on electromagnetic field and the interaction between particles. In MHD, plasma is treated as conctive fluid, which is described by hydrodynamics and Maxwell equations. This method only focuses on the average effect of fluid element, so it is an approximate method. Kinetic theory uses the method of statistical physics to consider the velocity distribution function of particles< Plasma astrophysics is a branch of astrophysics based on plasma physics. Most of the matter in the universe is plasma, so the research scope of plasma astrophysics is very wide, including corona, supernova remnant, AGN, compact star, interstellar medium and so on

astrophysicists had studied plasma before Langmuir, an American physicist, proposed the concept of plasma in 1929. In 1921, Milne established the stellar atmosphere theory according to Saha formula. In 1939, Danish astronomer strogen proposed that there were neutral hydrogen region and ionized hydrogen region in interstellar medium, which played an important role in interstellar medium and stellar evolution theory. The term plasma astrophysics came into being in the late 1960s. Plasma astrophysics uses the achievements of plasma physics in laboratory, and it can also get new results of significance to plasma physics

laboratory plasma physics usually deals with small-scale problems, while plasma astrophysics deals with large-scale cosmic plasma system, which is often in the state of optical thickness and has strong interaction with radiation and cosmic rays. In most cases, the cosmic plasma can be considered as homogeneous and boundless, which brings great convenience in the application of theoretical models. In addition, the characteristic scale of cosmic plasma is very large, so the magnetic Reynolds number is often very large, which has obvious magnetic freezing effect, that is, the magnetic lines of force are frozen on the fluid element and move with the motion of the fluid< Data source: wikinet

3. Plasma cleaner, also known as plasma surface treatment, is a new high-tech technology, which uses plasma to achieve the effect that conventional cleaning methods cannot achieve. Plasma cleaner
1. Basic knowledge of plasma: like solid, liquid or gas, plasma is a state of matter, also known as the fourth state of matter. When enough energy is applied to the gas to ionize it, it becomes a plasma state. The & quot; Activity & quot; The components include ion, electron, active group, excited nuclide (metastable state), photon, etc. Plasma surface treatment instrument is to use the properties of these active components to treat the sample surface, so as to achieve the purpose of cleaning, modification and photoresist ashing. 2. Principle of plasma cleaning: [1] plasma is a state of existence of matter. Generally, matter exists in three states: solid state, liquid state and gas state. However, in some special cases, there is a fourth state, such as matter in the ionosphere of the earth's atmosphere. There are the following substances in the plasma state: electrons in high-speed motion state; Neutral atoms, molecules and atomic groups (free radicals) in active state; Ionized atoms and molecules; Unreacted molecules, atoms, etc., but the substance remains electrically neutral on the whole. Plasma cleaning / etching technology is the particularity of plasma

4. I don't do packaging, but I often use RIE (reactive ion etch)

the principle is to etch semiconctor chips with plasma of various gases

the effect of plasma of different gases is different ~ the kind you say to remove foreign matters, I guess it should be oxygen (O2) or argon (AR)

I haven't heard of activating the surface

I don't think so.. 1. I don't think it's necessary. 2. Without mask, it's very dangerous to directly process the structure of the chip body on plasma.. The original structure may be damaged, resulting in chip damage

5.

Originally, I came to search for the answer to this question. I just read the introction of others. I'll borrow flowers and offer them to Buddha

1. principle of plasma cleaning:

< / OL >

clean the chamber under low pressure (using vacuum pump to pump air), inject Ar gas, and then add high voltage to the electrode in the chamber to ionize the gas in the inverted chamber. Due to the existence of electric field, the positive ions live on the negative electrode and the negative electrons run to the positive electrode, It will also impact the gas molecules in the chamber, forming a chain reaction. In the process of running to the negative electrode, Ar + ions will impact on the surface of the object to be cleaned, and react with the surface stains or foreign matter molecules to achieve the cleaning effect. Then vacuum pump is used to remove the dirty Ar gas in the chamber, so as to cycle

In general, plasma uses O2 or Ar as cleaning gas. As AR is inert gas, it is not easy to react with other objects. Therefore, in general, plasma uses AR, except for some special requirements

6. Basically, plasma has no view angle. LCD TV has the best viewing angle. Viewing from other angles, the system will change color and turn off white. Plasma has no e problem, but the system will reflect light. As for the price, LCD is more expensive than LCD, because LCD is too bright and slow to react with each other, because light TV system will affect color, Therefore, LCD TV can only achieve 17600000 colors at most (excluding Samsung), while plasma color depth can achieve 68.6 billion colors at most (in fact, it can be medium high)? Share number (all brands are water blowing) brightness refers to how many candlelight there are. For example, 500CD / m2 means that the lightest part of the machine is 500 candlelight. The only exception is dahuawang brand. If the contrast is high, the sense of hierarchy and scene can be good. View the original post & gt& gt;

7. Using 2.45GHz microwave energy (the same as household microwave oven) to excite the luminescent substance in the quartz bulb to generate molecular radiation and emit continuous visible light, special care should be taken when placing electronic equipment (such as computer mouse) close to or above the plasma lamp: not only the glass shell will heat, but also high voltage will cause a lot of static electricity to accumulate on the device, It's the same even with a plastic protective case.

8. The instrument can eliminate static electricity when measuring, but I don't know the principle