CN102387654A - Microscale low-temperature plasma jet generating device of atmospheric pressure - Google Patents

Abstract

The invention relates to an atmospheric pressure micro-scale low-temperature plasma jet generating device, which belongs to the technical field of low-temperature plasma. It is characterized in that the plasma jet is generated in the quartz glass tube, and the excitation electric field is established by a flat metal electrode placed on the opposite side of the quartz glass tube. Quartz glass plates are respectively placed on the upper and lower surfaces of the flat metal electrode, and the outside is positive An ultraviolet light source is placed near the position facing the quartz glass tube, the flat metal electrode is driven by a radio frequency power supply with pulse modulation function through a network matcher, and the other flat metal electrode is grounded. The effect and benefit of the present invention is to obtain the micro-scale plasma jet with no plasma pollution and the physical size can be changed in proportion under the condition of normal pressure, and control the gas temperature of the plasma by adjusting the pulse duty ratio, which can be used in biomedicine Sterilization and high-precision micro-nano machining and many other related fields have been applied.

Description

Atmospheric pressure microscale low temperature plasma jet generator

technical field

The invention belongs to the field of low-temperature plasma technology, and relates to an atmospheric-pressure micro-scale low-temperature plasma jet generating device used in the field of micro-nano etching technology and biomedicine for sterilization and disinfection. the

Background technique

An important branch derived from atmospheric pressure plasma technology after more than ten years of development is plasma jet technology. Focusing on the application of biological, medical, and industrial inorganic, organic, and metal materials surface modification and micro-nano etching processing, the research work of plasma jet technology is increasingly being researched by other disciplines such as medical, biological, and mechanical ultra-precision processing attention. Generating plasma under atmospheric pressure not only greatly reduces the investment in vacuum equipment because it does not require a vacuum environment, but also greatly increases the flexibility of combining and supporting plasma equipment with other equipment because the installation space is not limited by the vacuum chamber. Compared with charged particles, a large number of electrically neutral active free radicals generated in the plasma jet are more important and direct in terms of the number density of generated particles and the physical and chemical process of interacting with the processed materials. the

Usually, in the treatment of temperature-sensitive materials under atmospheric pressure and in the process of low-temperature precision machining, on the one hand, a low gas temperature is required, and on the other hand, the higher the plasma electron temperature, the more favorable it is to obtain active free radicals and various materials through physical and chemical processes. excited particles. In the commonly used technical method, increasing the power to obtain high electron temperature plasma often leads to the increase of gas temperature, which limits the application of many existing plasma jet forms. the

Contents of the invention

The object of the present invention is to provide an atmospheric pressure micro-scale low-temperature plasma jet generating device, which can realize the excitation and maintenance of the micro-scale plasma jet in the form of pulse modulation under atmospheric pressure. This device can obtain high electron temperature and The plasma of electron density controls the gas temperature of the plasma through the adjustment of the pulse duty ratio, so as to realize the requirements of various practical applications such as sterilization and high-precision micro-nano processing in biomedicine. the

The research technical idea of the present invention is to use a pulse-modulated radio frequency power supply to excite the atmospheric pressure plasma jet, and reduce the plasma temperature by adjusting the pulse duty cycle, and at the same time, a plasma with high electron density and high electron temperature can be generated during the pulse working period. Discharge and plasma jets of high-density active radicals; In addition, in order to avoid plasma pollution, we adopt the form of dielectric barrier discharge to excite the working gas in the dielectric tube laterally, so that compared with most of the plasma jets obtained by longitudinal excitation electric field In terms of the discharge form, the excitation and maintenance voltage is greatly reduced, so that other performance indicators of the power supply, such as ripple coefficient, etc., can be improved, thereby increasing the stability of the plasma; It is more conducive to the ionization and excitation in each discharge cycle, and can further reduce the required excitation and maintenance voltage. the

The technical scheme of the present invention is that the plasma jet is generated in the quartz glass tube 1, and the excitation electric field in the quartz glass tube is established by the flat metal electrodes 2 and 3 placed on the opposite sides of the quartz glass tube. Quartz glass plate 5 and quartz glass plate 4 are respectively placed on the upper and lower surfaces of the upper and lower surfaces to fix the whole flat metal electrodes 2 and 3 and the quartz glass tube 1, facing the quartz glass tube 1 on the outside of the quartz glass plates 4 and 5 The ultraviolet light source 8 and the ultraviolet light source 9 are respectively placed near the position so that the emitted ultraviolet light passes through the quartz glass plate 4 or 5 and the tube wall of the quartz glass tube 1 to irradiate the working gas flowing in the quartz glass tube 1, thus forming the Plasma discharge part; the flat metal electrode 2 is grounded, and the flat metal electrode 3 is driven by a radio frequency power supply 6 with a pulse modulation function through a network matcher 7; a jet of a corresponding size is installed at the jet output end of the quartz glass tube 1 according to actual requirements Shaping nozzle. the

The atmospheric pressure micro-scale low-temperature plasma jet generating device of the present invention, the radio frequency power supply 6 operating frequency is an industrial standard frequency of 13.56MHz, and the pulse modulation duty ratio varies within the range of 1% to 100%; the inner diameter of the quartz glass tube is taken as The value ranges from 3 micrometers to 2 millimeters; the quartz glass tube and the quartz glass plate material have the optical characteristics of low absorption of ultraviolet light, low scattering and high transmittance. the

The beneficial effect of the present invention is to obtain a micro-scale plasma jet with no plasma pollution and a proportionally changeable physical size under the condition of normal pressure and openness, and to control the gas temperature of the plasma by adjusting the pulse duty cycle, which can be used in biomedicine Sterilization and high-precision micro-nano machining and many other related fields have been applied. the

Description of drawings

The accompanying drawing is a structural schematic diagram of an atmospheric pressure micro-scale low-temperature plasma jet generating device. the

In the figure: 1 quartz glass tube; 2 flat metal electrode; 3 flat metal electrode; 4 quartz glass plate; 5 quartz glass plate; 6 radio frequency power supply; 7 network matcher; 8 ultraviolet light source; 9 ultraviolet light source. the

Detailed ways

The specific embodiments of the present invention will be described in detail below in conjunction with the technical solutions and accompanying drawings. the

Firstly, feed the carrier gas into the quartz glass tube 1 and set the working mode of the RF power supply 6 to continuous output mode, turn on the UV light source 8 and UV light source 9, connect the RF power supply 6, adjust the output voltage of the RF power supply and network matching The device 7 makes the plasma discharge generated in the quartz glass tube 1 stable and fills the whole quartz glass tube 1, and then, adds an active working gas in a certain proportion, and adjusts the output voltage of the radio frequency power supply, the radiation intensity of the ultraviolet light sources 8 and 9, and The network matcher 7 minimizes the reflected power and stabilizes the discharge state, then adjusts the modulation frequency of the RF power supply 6 to control the temperature of the plasma according to the requirements of the application, and sprays the generated plasma jet at a certain distance and angle. On the surface of the sample to be treated or processed. the

Claims (2)

1. An atmospheric pressure micro-scale low-temperature plasma jet generating device is composed of a radio frequency power supply (6) with a pulse modulation function, a network matcher (7), and a plasma discharge component. It is characterized in that: the plasma jet is in a quartz glass tube Generated in (1), the excitation electric field in the quartz glass tube is established by the flat metal electrodes (2) and (3) placed on the opposite sides of the quartz glass tube, on the upper surface and the lower surface of the flat metal electrode Place the quartz glass plate (5) and the quartz glass plate (4) respectively to fix the whole flat metal electrodes (2) and (3) and the quartz glass tube (1), on the outside of the quartz glass plate (4) and (5) A UV light source (8) and a UV light source (9) are respectively placed near the position facing the quartz glass tube (1) so that the emitted UV light passes through the quartz glass plate (4) or (5) and the quartz glass tube (1) The tube wall irradiates the working gas flowing through the quartz glass tube (1), thus forming the plasma discharge part; the flat metal electrode (2) is grounded, and the flat metal electrode (3) is powered by a radio frequency power supply with pulse modulation function (6) Driven by a network matcher (7); a jet shaping nozzle of a corresponding size is installed at the jet output end of the quartz glass tube (1) according to actual requirements. 2. A kind of atmospheric pressure micro-scale low-temperature plasma jet generating device according to claim 1, characterized in that the operating frequency of the radio frequency power supply is an industry standard frequency of 13.56MHz, and the pulse modulation duty cycle is between 1% and 100 % range; the inner diameter of the quartz glass tube ranges from 3 microns to 2 mm; the quartz glass tube and the quartz glass plate material have the optical characteristics of low absorption of ultraviolet light, low scattering and high transmittance. the

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