阅读说明：本技术 一种等离子刻蚀机及其使用方法 (Plasma etching machine and using method thereof ) 是由 郭颂 刘海洋 王铖熠 李娜 刘小波 张军 胡冬冬 许开东 于 2020-04-29 设计创作，主要内容包括：本发明提出了一种等离子刻蚀机及其使用方法,该等离子刻蚀机包括一刻蚀腔体和一加热板；刻蚀腔体的敞开端固定一陶瓷介质窗；陶瓷介质窗的上方固定一产生等离子体的等离子体耦合线圈；加热板固定在一屏蔽罩内；屏蔽罩的下端敞开；屏蔽罩位于刻蚀腔体的上方且固定在刻蚀腔体上；加热板固定在陶瓷介质窗朝向等离子体耦合线圈的表面；加热板上开设用于供等离子体穿过的预留间隙；加热板通过一供电电路连接一加热电源。本发明将加热板直接贴合在陶瓷介质窗上,通过对加热板通电以对陶瓷介质窗直接进行加热。因此加热板的加热效率高,热量散失少,避免屏蔽罩的过热现象,无需在屏蔽罩外增设保护罩。(The invention provides a plasma etching machine and a using method thereof, wherein the plasma etching machine comprises an etching cavity and a heating plate; a ceramic dielectric window is fixed at the open end of the etching cavity; a plasma coupling coil for generating plasma is fixed above the ceramic dielectric window; the heating plate is fixed in a shielding case; the lower end of the shielding cover is open; the shielding cover is positioned above the etching cavity and fixed on the etching cavity; the heating plate is fixed on the surface of the ceramic dielectric window facing the plasma coupling coil; a reserved gap for plasma to pass through is formed in the heating plate; the heating plate is connected with a heating power supply through a power supply circuit. According to the invention, the heating plate is directly attached to the ceramic dielectric window, and the ceramic dielectric window is directly heated by electrifying the heating plate. Therefore, the heating plate has high heating efficiency and less heat loss, avoids the overheating phenomenon of the shielding cover, and does not need to additionally arrange a protective cover outside the shielding cover.)

1. A plasma etcher comprises an etching cavity and a heating plate; a ceramic dielectric window is fixed at the open end of the etching cavity; a plasma coupling coil for generating plasma is fixed above the ceramic dielectric window; the heating plate is fixed in a shielding cover; the lower end of the shielding cover is open; the shielding cover is positioned above the etching cavity and fixed on the etching cavity; the method is characterized in that:

the heating plate is fixed on the surface of the ceramic dielectric window facing the plasma coupling coil; a reserved gap for the plasma to pass through is formed in the heating plate; the heating plate is connected with a heating power supply through a power supply circuit.

2. The plasma etcher of claim 1 wherein the upper section of the ceramic dielectric window is secured within the shield.

3. The plasma etcher of claim 1 wherein the heater plate is circular; the heating plate comprises a plurality of heating wires distributed along the circumference; and the reserved gap is formed by surrounding the adjacent heating wires.

4. The plasma etcher of claim 1, further comprising a temperature control unit for adjusting a heating temperature;

the temperature control unit includes: the input end of the temperature controller is electrically connected with a temperature measuring sensor; the temperature sensor is fixed on the heating plate; the output end of the temperature controller is electrically connected with a heating power supply; a solid-state relay is arranged between the temperature controller and the heating power supply; the solid-state relay is arranged on the power supply circuit.

5. The plasma etcher as claimed in claim 4, further comprising an auxiliary temperature sensor for monitoring a heating temperature and an alarm;

the input end of the warning indicator is electrically connected with the auxiliary temperature measuring sensor; the auxiliary temperature measuring sensor is fixed on the heating plate.

6. The use method of the plasma etching machine is based on the plasma etching machine of claim 5, and is characterized by comprising the following steps:

(1) the temperature sensor senses the temperature of the ceramic dielectric window and transmits data to the temperature controller; when the temperature of the ceramic dielectric window reaches the temperature set by the temperature controller, the temperature controller controls the solid-state relay to be switched off; the auxiliary temperature measuring sensor monitors the temperature of the heating plate in real time and transmits data to the warning indicator; the warning indicator displays the temperature of the heating plate in real time;

(2) when the temperature of the ceramic dielectric window is reduced to the temperature set by the temperature controller, the temperature controller controls the solid relay to be closed, the power supply circuit is communicated with the heating power supply and the heating plate, and the heating plate heats the ceramic dielectric window; the auxiliary temperature measuring sensor monitors the temperature of the heating plate in real time and transmits data to the warning indicator; the warning indicator displays the temperature of the heating plate in real time; therefore, the temperature control of the ceramic dielectric window is realized;

(3) when the temperature controller and/or the temperature measuring sensor are damaged, the warning indicator displays the temperature and gives an alarm to manually turn off the power supply.

Technical Field

The invention belongs to the technical field of machining equipment, and particularly relates to a plasma etching machine and a using method thereof.

Background

The plasma etcher is used for processing the surface of a substrate placed in a cavity of the etcher by introducing reaction gas containing proper etchant or deposition source gas into the cavity of the vacuum etcher and then applying radio frequency energy to the cavity of the vacuum etcher to dissociate the reaction gas to generate plasma. The plasma etching machine mainly comprises a forevacuum chamber, an etching cavity, an air supply system and a vacuum system. The etching cavity mainly comprises the following components: the plasma coupling coil, the ceramic dielectric window, the ICP radio frequency unit, the RF radio frequency unit, the lower electrode system, the temperature control system and the like. The plasma coupling coil is positioned outside the upper vacuum of the cavity, the ceramic dielectric window is positioned between the cavity and the plasma coupling coil, the ceramic dielectric window can seal vacuum and does not influence the penetration of plasma into the cavity, but in the plasma etching process, etched products can be deposited on the ceramic dielectric window, the deposition for a long time can generate adverse effect on the plasma, and particles can also be generated to influence the etching process. In general, ceramic dielectric window heating is an important means of reducing deposition. At present, the ceramic dielectric window of the existing plasma etching machine is heated by adopting a hot air heating mode, but the heating mode has the problems that the heating efficiency is low due to the fact that hot air is scattered, the side wall outside the ceramic dielectric window is easy to generate high temperature, an operator is easy to scald, components are easy to damage and the like, a very complicated protection device is needed, the cost is high, and heat dissipation is not facilitated. Fig. 1-2 show a heating device for a ceramic dielectric window of a conventional plasma etcher, which includes a plasma coupling coil 1, a ceramic dielectric window 2, a metal inner shield 3, a heating net 4, a heat-sending fan 5 and an outer shield 6. The plasma coupling coil 1 generates plasma which penetrates through the ceramic dielectric window 2, reaction gas is introduced into the etching cavity 22, the reaction gas and the plasma coupling coil 1 jointly carry out an etching process on the substrate piece, meanwhile, the heating net 4 generates heat, the heat is blown to the ceramic dielectric window 2 through the heat-sending fan 5 according to the direction shown by an arrow of a schematic diagram to be heated, the temperature of the metal inner shielding cover 3 is higher and higher along with the wind heat, the metal inner shielding cover is easy to damage an operator, and the outer shielding cover 6 is arranged to protect. As shown in fig. 2, the ceramic dielectric window 2 is fixed on the inner wall of the etching chamber 22 by a fastener, the plasma coupling coil 1 is located above the ceramic dielectric window, and the plurality of plasma coupling coils 1 are connected by an insulating plate and then fixed on the inner wall of the metal inner shield 3 by a fastener.

In summary, the heating method in the prior art has the following disadvantages: 1) the heat of the metal inner shielding cover 3 is dissipated by the heat supply fan 5, so that the heating efficiency of the heating net is low; 2) when heating net 4 heats ceramic dielectric window 2, also heats plasma coil 1 and other electrical components such as matcher simultaneously, and 3 high temperatures of metal inner shield cover for avoiding metal inner shield cover 3 to hurt people set up outer shield cover 6 outside, lead to this heating structure's structure complicated, both occupy extra space and increase cost again.

Disclosure of Invention

The invention aims to provide a plasma etching machine and a using method thereof. Therefore, the heating plate has high heating efficiency and less heat loss, avoids the overheating phenomenon of the shielding cover, and does not need to additionally arrange a protective cover outside the shielding cover. In the heating process, due to the design of the reserved gap of the heating plate, the influence of the heating plate on the plasma can be avoided. In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a plasma etching machine, which comprises an etching cavity and a heating plate, wherein the etching cavity is provided with a plurality of grooves; a ceramic dielectric window is fixed at the open end of the etching cavity; a plasma coupling coil for generating plasma is fixed above the ceramic dielectric window; the heating plate is fixed in a shielding cover; the lower end of the shielding cover is open; the shielding cover is positioned above the etching cavity and fixed on the etching cavity;

the heating plate is fixed on the surface of the ceramic dielectric window facing the plasma coupling coil; a reserved gap for the plasma to pass through is formed in the heating plate; the heating plate is connected with a heating power supply through a power supply circuit.

Preferably, the upper section of the ceramic dielectric window is fixed in the shielding case.

Preferably, the heating plate is circular; the heating plate comprises a plurality of heating wires distributed along the circumference; and the reserved gap is formed by surrounding the adjacent heating wires.

Preferably, the heating device further comprises a temperature control unit for adjusting the heating temperature;

the temperature control unit includes: the input end of the temperature controller is electrically connected with a temperature measuring sensor; the temperature sensor is fixed on the heating plate; the output end of the temperature controller is electrically connected with a heating power supply; a solid-state relay is arranged between the temperature controller and the heating power supply; the solid-state relay is arranged on the power supply circuit.

Preferably, the heating device further comprises an auxiliary temperature measuring sensor for monitoring the heating temperature and an alarm;

the input end of the warning indicator is electrically connected with the auxiliary temperature measuring sensor; the auxiliary temperature measuring sensor is fixed on the heating plate.

The invention also provides a using method of the plasma etching machine, and the using method comprises the following steps based on the plasma etching machine:

(1) the temperature sensor senses the temperature of the ceramic dielectric window and transmits data to the temperature controller; when the temperature of the ceramic dielectric window reaches the temperature set by the temperature controller, the temperature controller controls the solid-state relay to be switched off; the auxiliary temperature measuring sensor monitors the temperature of the heating plate in real time and transmits data to the warning indicator; the warning indicator displays the temperature of the heating plate in real time;

(2) when the temperature of the ceramic dielectric window is reduced to the temperature set by the temperature controller, the temperature controller controls the solid relay to be closed, the power supply circuit is communicated with the heating power supply and the heating plate, and the heating plate heats the ceramic dielectric window; the auxiliary temperature measuring sensor monitors the temperature of the heating plate in real time and transmits data to the warning indicator; the warning indicator displays the temperature of the heating plate in real time; therefore, the temperature control of the ceramic dielectric window is realized;

(3) when the temperature controller and/or the temperature measuring sensor are damaged, the warning indicator displays the temperature and gives an alarm to manually turn off the power supply.

Compared with the prior art, the invention has the advantages that:

(1) the heating plate is directly attached to the ceramic dielectric window, and the ceramic dielectric window is directly heated by the heating plate through electrifying the heating plate, so that heat loss is less. Therefore, the heating efficiency of the heating plate is high.

(2) Because the heat loss is less, the overheating phenomenon of the shielding cover is avoided, and a heat sending fan does not need to be added and a protective cover is additionally arranged outside the shielding cover, so that the plasma etching machine has small occupied space and simple structure.

(3) In the heating process, due to the design of the reserved gap of the heating plate, the influence of the heating plate on the smooth passing of the plasma can be avoided, and the smooth proceeding of the heating process and the etching process is ensured.

Drawings

FIG. 1 is a block diagram of a heating plate of a prior art plasma etcher;

FIG. 2 is a top view of the ceramic dielectric window and the plasma coupling coil of FIG. 1;

FIG. 3 is a front view of a plasma etcher in accordance with one embodiment of the present invention;

FIG. 4 is a cross-sectional view of the heating panel of FIG. 3;

FIG. 5 is a top view of the heating panel of FIG. 3;

fig. 6 is a connection diagram of the temperature control unit in fig. 3.

The plasma temperature measuring device comprises a plasma coupling coil 1, a ceramic dielectric window 2, a metal inner shield 3, a heating net 4, a heat sending fan 5, a heat sending fan 6, an outer shield 7, a heating device 8, a shield 9, a heating plate 10, a first matching network 11, an excitation radio frequency power supply 12, a gas source 13, a temperature controller 14, a solid-state relay 15, a heating power supply 16, a temperature measuring sensor 17, a plasma 18, a substrate sheet 18, a power supply circuit 19, a bias electrode 20, a bias radio frequency power supply 21, an etching cavity 22, a pressure control valve 23, a vacuum pump 24, a second matching network 25, an alarm 26 and an auxiliary temperature measuring sensor 27.

Detailed Description

The present invention will now be described in more detail with reference to the accompanying schematic drawings, in which preferred embodiments of the invention are shown, it being understood that one skilled in the art may modify the invention herein described while still achieving the advantageous effects of the invention. Accordingly, the following description should be construed as broadly as possible to those skilled in the art and not as limiting the invention.

In the plasma etcher in the prior art, as shown in fig. 3, the pre-vacuum chamber includes a pre-pumping pipeline, a pre-pumping valve, a foreline, and a forevalve, the pre-pumping pipeline is communicated with the etching chamber 22, and the forevalve is communicated with the dry pump and the vacuum pump; the vacuum system includes an etching chamber 22, a pressure control valve 23 and a vacuum pump 24. As shown in fig. 1-2, the metal inner shield 3 and the metal outer shield 6 are both located above the etching cavity 22; the lower ends of the metal inner shielding case 3 and the outer shielding case 6 are both open; the upper end of the etching chamber 22 is open; the ceramic dielectric window 2 is fixed at the open end of the etching cavity; the plasma coupling coil 1 is fixed above the coil ceramic dielectric window 2; the plasma coupling coils 1 are all fixed in a metal inner shielding cover 3; the upper section of the ceramic dielectric window 2 is fixed in a metal inner shielding cover 3; the lower section of the ceramic dielectric window 2 is fixed in the etching cavity 22; i.e. the ceramic dielectric window 2 is located between the metal inner shield 3 and the etching chamber 22.

As shown in fig. 3, a plasma etcher is improved on the basis of the existing plasma etcher by a heating device 7, and comprises a shielding case 8, a ceramic dielectric window 2, an etching chamber 22, a heating plate 9 and a plasma coupling coil 1 for generating plasma 17.

The lower ends of the shielding cases 8 are all opened; the upper end of the etching chamber 22 is open; the ceramic dielectric window 2 is fixed at the open end of the etching cavity 22; the plasma coupling coil 1 is fixed above the coil ceramic dielectric window 2; the plasma coupling coil 1 is fixed in a shielding case 8; the lower section of the ceramic dielectric window 2 is fixed in the etching cavity 22; the upper section of the ceramic dielectric window 2 is fixed in a shielding case 8; the shield 8 and the etching chamber 22 are fixed together by fasteners.

The etching working principle of the plasma etching machine is as follows: the plasma coupling coil 1 (radio frequency coil) generates plasma 17 under the combined action of the excitation radio frequency power supply 11 and the first matching network 10, the gas source 12 introduces reaction gas into the etching cavity, the plasma 17 and the reaction gas etch the substrate sheet 18 together, and reaction products in the etching process are continuously deposited on the ceramic dielectric window 2. The bias electrode 20 accelerates the plasma under the combined action of the bias radio frequency power supply 21 and the second matching network 25; when the vacuum pressure in the etching chamber 22 is insufficient, the external control device opens the pressure control valve 23, and the vacuum pump 24 pumps the vacuum pump 24 into the etching chamber 22.

As shown in fig. 3 to 4, a heating device 7 is added inside the conventional plasma etcher, and the heating device 7 includes a heating plate 9 for heating the ceramic dielectric window 2; the heating plate 9 is fixed on the surface of the ceramic dielectric window 2 facing the plasma coupling coil 1; a reserved gap for the plasma 17 to pass through is formed in the heating plate 9; the heating plate is connected to a heating power supply 15 via a power supply circuit 19. As shown in fig. 5, the heating plate 9 is preferably circular and includes a plurality of heating wires distributed along the circumference; the heating wires are petal-shaped; a reserved gap for passing through the plasma 17 is enclosed between the adjacent heating wires.

As shown in fig. 3 and 6, in order to control the temperature of the ceramic dielectric window 2 by the heating plate 9, the heating device 7 further includes a temperature control unit for adjusting the heating temperature of the ceramic dielectric window 2; the temperature control unit includes: a temperature controller 13, a temperature sensor 16 and a solid state relay 14. The input end of the temperature controller 13 is electrically connected with a temperature measuring sensor 16; the temperature sensor 16 is fixed on the heating plate 9; the output end of the temperature controller 13 is electrically connected with a heating power supply 15; a solid-state relay 14 is arranged between the temperature controller 13 and the heating power supply 15; the solid-state relay 14 is also arranged on the supply circuit 19.

Preferably, to avoid the failure of the temperature sensor 16 or the temperature controller 13, the heating device 7 further comprises an auxiliary temperature sensor 27 and an alarm 26; the input end of the alarm 26 is electrically connected with the auxiliary temperature measuring sensor 27; the auxiliary temperature sensor 27 is fixed to the heating plate 9.

The auxiliary temperature measuring sensor 27 monitors the temperature of the heating plate in real time and transmits data to the alarm 26; when the temperature measuring sensor 16, the temperature controller 13 and the relay 14 are not damaged normally, the alarm 26 is only used for displaying the temperature of the heating plate in real time; when one of the temperature sensor 16, the temperature controller 13 or the relay 14 is damaged, the alarm 26 displays the temperature and gives an alarm to remind the worker of being in place, so that the power supply is manually turned off.

The embodiment also provides a use method of the plasma etching machine, which comprises the following steps:

(1) the temperature sensor 16 senses the heating temperature of the ceramic dielectric window 2 and transmits data to the temperature controller 13; when the temperature of the ceramic dielectric window 2 reaches a first temperature set by the temperature controller 13, the temperature controller 13 controls the solid-state relay 14 to be switched off, and a circuit between the heating power supply 15 and the temperature controller 13 is switched off; the auxiliary temperature measuring sensor 27 monitors the temperature of the heating plate 9 in real time and transmits data to the alarm 26; the alarm 26 displays the temperature of the heating plate 9 in real time.

(3) When the temperature of the ceramic dielectric window 2 is reduced to a second temperature set by the temperature controller 13, the temperature controller 13 controls the solid-state relay 14 to be closed, the power supply circuit 19 is communicated with the heating power supply 15 and the heating plate 9, and the heating plate 9 heats the ceramic dielectric window 2; the auxiliary temperature measuring sensor 27 monitors the temperature of the heating plate 9 in real time and transmits data to the alarm 26; the alarm 26 displays the temperature of the heating plate 9 in real time; thereby, the temperature control of the ceramic dielectric window 2 is realized.

(3) When the temperature controller 13 and/or the temperature measuring sensor 16 are damaged, the alarm 26 displays the temperature and gives an alarm to remind the worker to put in place, so that the power supply is manually turned off.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any way. It will be understood by those skilled in the art that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.