Particle differential mobility analyzer

Abstract

A particle differential mobility analyzer includes a mass flow controller, a temperature sensor, a pressure sensor and a particle separation chamber. The mass flow controller is controlled to output clean dry gas at a mass flow rate. A control device adjusts the mass flow rate to the first volume flow rate according to the temperature and pressure sensed. The particle separation chamber includes a clean gas receiving end, an airgel receiving end, a mixed gas outputting end and a residual gas exhausting end. The clean gas receiving end receives the clean dry gas inputted at the first volume flow rate. The airgel receiving end receives the airgel inputted at a second volume flow rate. The mixed gas outputting end pumps out the mixed mixed aerogel at a third volume flow rate, and the residual gas exhausting end exhausts the remaining mixed aerogel at a fourth volume flow rate. The third volume flow rate is equal to the second volume flow rate, and the fourth volume flow rate is equal to the first volume flow rate. Volume flow.

Description

[Technical Field]

[0001] This invention relates to the field of detection, and in particular to a particle differential electromigration analyzer. [Previous Technology]

[0002] With the evolution of semiconductor manufacturing processes, key dimensions have been shrunk to the nanometer level, and particle specifications in the overall process environment, equipment, raw materials, and process solutions have become increasingly stringent. Generally speaking, the monitoring of particles in the process solution is achieved by atomizing the particles into an aerogel, and then using a particle separator to separate the particles according to their size by setting a constant electric field and flow rate.

[0003] Traditional particle separators are internal circulation type. However, the process solution contains corrosive solutions, such as hydrochloric acid, sulfuric acid, hydrogen peroxide, etc. After long-term internal circulation, the concentration may accumulate, which may cause corrosion of internal components. This may lead to the destruction of the entire equipment, and both the equipment cost and the downtime cost are quite expensive. Therefore, methods of introducing clean gas from the outside have also been developed, which can avoid the accumulation of corrosive aerogels and even further rapidly metabolize them, thereby avoiding corrosion of internal components.

[0004] However, the most common problem with particle separators that use externally supplied clean air is the instability of the intake air volume. Currently, float-type flow meters are often used to calculate the volumetric flow rate of the intake air. However, since float-type flow meters are mostly analog, they are difficult to control precisely and may lead to misjudgment of particle separation, which may result in huge errors in the judgment of micro-processes. [Summary of the Invention]

[0005] To address the aforementioned problems, a particle differential electromigration analyzer is provided. The particle differential electromigration analyzer includes a mass flow control device, a temperature sensor, a pressure sensor, and a particle separation chamber. The mass flow control device is connected to a clean, dry gas storage tank and electrically connected to a control device, outputting clean, dry gas at a mass flow rate. The temperature and pressure sensors are connected to the mass flow control device and electrically connected to the control device, sensing the temperature and pressure of the clean, dry gas, and generating temperature and pressure information for the control device. The control device adjusts the mass flow rate to a first volumetric flow rate based on the temperature and pressure information.

[0006] The particle separation chamber is subjected to an electric field and includes a clean gas receiving end, an aerogel receiving end, a mixed gas output end, and a residual gas discharge end. The clean gas receiving end is connected to a mass flow control device and receives clean, dry gas input at a first volumetric flow rate. The aerogel receiving end receives aerogel input at a second volumetric flow rate. The mixed gas output end extracts a mixed aerogel of aerogel and clean, dry gas at a third volumetric flow rate, wherein the third volumetric flow rate is equal to the second volumetric flow rate and less than the first volumetric flow rate. The residual gas discharge end discharges the remaining mixed aerogel at a fourth volumetric flow rate, wherein the fourth volumetric flow rate is equal to the first volumetric flow rate.

[0007] In some embodiments, the output terminal of the mixed gas is connected to a counting device, the counting device is further electrically connected to a control device, and outputs flow information to the control device. When the counting device adjusts the third volume flow rate, the control device controls the change of the first volume flow rate according to the flow information, temperature information and pressure information, wherein the sum of the first volume flow rate and the second volume flow rate is equal to the sum of the third volume flow rate and the fourth volume flow rate.

[0008] In some embodiments, the aerogel receiver is connected to a manifold, which includes a connection end, an output end, and a bypass end. The output end is connected to the aerogel receiver, and the inlet gas flow rate input through the connection end is equal to the sum of the second volumetric flow rate output through the output end and the bypass gas output flow rate output through the bypass end.

[0009] In some embodiments, the first volumetric flow rate and the fourth volumetric flow rate are between 2 and 20 L / min, the second volumetric flow rate and the third volumetric flow rate are between 0.2 and 4 L / min, and the sum of the first volumetric flow rate and the second volumetric flow rate is between 2.2 and 25 L / min.

[0010] More specifically, in some embodiments, the first volumetric flow rate and the fourth volumetric flow rate are between 12 and 18 L / min, the second volumetric flow rate and the third volumetric flow rate are between 0.8 and 2.5 L / min, and the sum of the first volumetric flow rate and the second volumetric flow rate is between 12 and 18 L / min.

[0011] In some embodiments, the residual gas discharge end includes a perforated plate and is connected to a vacuum pump, the vacuum pump and the perforated plate controlling the extraction of the remaining mixed aerogel at a fourth volume flow rate.

[0012] More specifically, in some embodiments, the vacuum pump is electrically connected to the control device, and when the orifice plate is replaced, the control device changes the first volume flow rate according to the fourth volume flow rate changed by the vacuum pump.

[0013] In some embodiments, the residual gas discharge end further includes a second mass flow control device, a second temperature sensor, and a second pressure sensor. The second mass flow control device, the second temperature sensor, and the second pressure and temperature sensor are electrically connected to a control device. The second mass flow control device controls the remaining mixed aerogel to be discharged at a second mass flow rate. The second temperature sensor and the second pressure sensor sense the temperature and pressure of the mixed aerogel and generate second temperature information and second pressure information to the control device. The control device adjusts the second mass flow rate to a fourth volumetric flow rate based on the second temperature information and the second pressure information.

[0014] In some embodiments, when the control device controls the second mass control device to change the fourth volume flow rate, it simultaneously controls the mass flow rate control device to change the first volume flow rate.

[0015] In some embodiments, the particle separation chamber includes a plurality of particle collection slots, wherein a plurality of particles in the aerogel are separated according to their particle size based on an electric field and a first volume flow rate and are guided to the particle collection slots.

[0016] As described in the foregoing embodiments, the mass flow control device, pressure sensor and temperature sensor can effectively control the intake and exhaust volumes of the particle separation chamber to be consistent and can be programmed. In a non-internal circulation system, it can ensure that the separation of particles does not cause misjudgment and can be applied to more precise processes.

Implementation Method

[0018] Figure 1 is a block diagram of a first embodiment of a particle differential electromigration analyzer. As shown in Figure 1, the particle differential electromigration analyzer 100 includes a mass flow control device 10, a temperature sensor 20, a pressure sensor 30, and a particle separation chamber 40. The mass flow control device 10 is connected to a clean and dry gas storage tank 400 and electrically connected to a control device 200, outputting clean and dry gas CA at a mass flow rate. The temperature sensor 20 and the pressure sensor 30 are connected to the mass flow control device 10 and electrically connected to the control device 200, sensing the temperature and pressure of the clean and dry gas, and generating temperature information T and pressure information P to the control device 200. The control device 200 adjusts the mass flow rate to a first volumetric flow rate based on the temperature information T and the pressure information P.

[0019] The particle separation chamber 40 is subjected to an electric field E and includes a clean gas receiving end 41, an aerogel receiving end 43, a mixed gas output end 45, and a residual gas discharge end 47. The clean gas receiving end 41 can be connected to the mass flow control device 10 through a pipeline to receive clean dry gas CA input at a first volume flow rate. The aerogel receiving end 43 receives aerogel A input at a second volume flow rate. The mixed gas output end 45 extracts a mixed aerogel M of aerogel A and clean dry gas CA at a third volume flow rate and outputs it to the counting device 300, wherein the third volume flow rate is equal to the second volume flow rate and the third volume flow rate is less than the first volume flow rate. The residual gas discharge end 47 discharges the remaining mixed aerogel MR at a fourth volume flow rate, wherein the fourth volume flow rate is equal to the first volume flow rate.

[0020] More specifically, the particle separation chamber 40 includes a plurality of particle collection tanks, wherein the plurality of particles in the aerogel A are separated according to their different particle sizes based on the electric field E and the first volume flow rate, and are guided to the particle collection tanks.

[0021] Here, the particle separation chamber 40 maintains the intake air volume of the aerogel receiving end 43 through the manifold 50, while the mixed gas output end 45 is connected to the downstream counting device 300 to extract a constant volume using a vacuum pump (not shown in the figure), and the residual gas discharge end 47 is connected to the vacuum pump 60 to also extract a constant volume. Therefore, the second, third, and fourth volume flow rates are approximately constant values. The details will be described in detail later. Research shows that the problem of unbalanced volume flow rates can be mainly attributed to the inability to accurately control the first volume flow rate of the clean gas receiving end 41, resulting in a discrepancy with the fourth volume flow rate. Here, a programmable mass flow control device 10 is used instead of a float flow meter, and the gas equation PV=nRT is used to calculate the incoming volume flow rate through the temperature sensor 20 and pressure sensor 30, thereby maintaining the overall flow balance, avoiding instability in the intake air volume, and avoiding misjudgment of particle size in particle separation.

[0022] More specifically, in some embodiments, the first and fourth volumetric flow rates are between 2 and 20 L / min, preferably between 12 and 18 L / min, for example, 15 L / min. The second and third volumetric flow rates are between 0.2 and 4 L / min, preferably between 0.8 and 2.5 L / min, for example, 1.5 L / min. And the sum of the first and second volumetric flow rates is between 2.2 and 25 L / min, preferably between 12 and 18 L / min.

[0023] More specifically, in some embodiments, the aerogel receiver 43 is connected to a manifold 50, which includes a connection end 51, an output end 53, and a bypass end 55. The output end 53 is connected to the aerogel receiver 43 to input aerogel A into the particle separation chamber 40 at a constant volumetric flow rate, i.e., a second volumetric flow rate. The connection end 51 is connected to the atomizing device 500 from the front end, while the bypass end 55 acts as a bypass to discharge aerogel A exceeding the second volumetric flow rate. Here, the intake gas flow rate input from the atomizing device 500 is equal to the sum of the second volumetric flow rate output from the output end 53 and the bypass gas output flow rate output from the bypass end 55.

[0024] In addition, the residual gas discharge end 47 includes an orifice plate 471 and is connected to a vacuum pump 60. The orifice plate 471 restricts the discharge volume, thereby allowing the vacuum pump 60 and the orifice plate 471 to control the extraction of the remaining mixed aerogel MR at a fourth volumetric flow rate. Furthermore, the vacuum pump 60 can also be electrically connected to a control device 200. When the orifice plate 471 is replaced, the orifice diameter and volumetric flow rate of the pump are adjusted. The control device 200 controls the change of the first volumetric flow rate according to the fourth volumetric flow rate changed by the vacuum pump 60.

[0025] In some embodiments, the counting device 300 is also electrically connected to the control device 200 and outputs flow information IR to the control device 200. When the counting device 300 adjusts the third volume flow rate, the control device 200 controls the change of the first volume flow rate according to the flow information IR, the control temperature information T and the pressure information P, so as to maintain the sum of the first volume flow rate and the second volume flow rate equal to the sum of the third volume flow rate and the fourth volume flow rate.

[0026] Figure 2 is a block diagram of a second embodiment of the particle differential electromigration analyzer. As shown in Figure 2, and referring to Figure 1, the difference from the first embodiment is that the residual gas discharge end 47 is not configured as a combination of orifice plate 471 and vacuum pump 60, but as a combination of second mass flow control device 71, second temperature sensor 73, and second pressure sensor 75. The second mass flow control device 71, second temperature sensor 73, and second pressure sensor 75 are electrically connected to the control device 200. The second mass flow control device 71 controls the remaining mixed aerogel MR to be discharged at a second mass flow rate. The second temperature sensor 73 and second pressure sensor 75 sense the temperature and pressure of the mixed aerogel M and generate second temperature information T2 and second pressure information P2 to the control device 200. The control device 200 adjusts the second mass flow rate to a fourth volumetric flow rate according to the second temperature information T2 and the second pressure information P2. At the same time, the control device 200 also adjusts the first volumetric flow rate according to the fourth volumetric flow rate, thereby achieving a dynamic balance of flow rates.

[0027] Further, when the control device 200 controls the second mass flow control device 71 to change the fourth volume flow, it simultaneously controls the mass flow control device 10 to change the first volume flow, thereby changing the first volume flow.

[0028] In summary, through the mass flow control device 10, temperature sensor 20 and pressure sensor 30, the intake and exhaust volumes of the particle separation chamber 40 are effectively controlled to be consistent, and precise program control can be performed. In a non-internal circulation system, it can ensure that the separation of particles does not cause misjudgment, and can be applied to more precise processes.

[0029] Although the technical content of the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any modifications and refinements made by those skilled in the art without departing from the spirit of the present invention should be included within the scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims. [Simplified Explanation of the Diagram]

[0017] Figure 1 is a block diagram of a first embodiment of the particle differential electromigration analyzer. Figure 2 is a block diagram of a second embodiment of the particle differential electromigration analyzer.

Claims

1. A particle differential electromigration analyzer, comprising: a mass flow control device connected to a clean and dry gas storage tank and electrically connected to a control device, for outputting a clean and dry gas at a mass flow rate; a temperature sensor and a pressure sensor connected to the mass flow control device and electrically connected to the control device, for sensing the temperature and pressure of the clean and dry gas, and generating temperature information and pressure information to the control device, wherein the control device adjusts the mass flow rate to a first volumetric flow rate based on the temperature information and the pressure information; and a particle separation chamber subjected to an electric field, comprising: a clean gas receiving end connected to the mass flow control device for receiving the clean and dry gas input at the first volumetric flow rate; and an aerogel receiving end for receiving an aerogel input at a second volumetric flow rate. A mixed gas output terminal extracts a mixed aerogel containing the aerogel and the clean, dry gas at a third volumetric flow rate, wherein the third volumetric flow rate is equal to the second volumetric flow rate and the third volumetric flow rate is less than the first volumetric flow rate; and a residual gas discharge terminal discharges a remaining mixed aerogel at a fourth volumetric flow rate, wherein the fourth volumetric flow rate is equal to the first volumetric flow rate.

2. The particle differential electromigration analyzer as described in claim 1, wherein the output terminal of the mixed gas is connected to a counting device, the counting device is further electrically connected to the control device, and outputs flow rate information to the control device, wherein when the counting device adjusts the third volume flow rate, the control device controls and changes the first volume flow rate according to the flow rate information, the temperature information, and the pressure information, wherein the sum of the first volume flow rate and the second volume flow rate is equal to the sum of the third volume flow rate and the fourth volume flow rate.

3. The particle differential electromigration analyzer as claimed in claim 1, wherein the aerogel receiver is connected to a manifold, the manifold including a connection end, an output end and a bypass end, the output end being connected to the aerogel receiver, and an inlet gas flow rate input through the connection end being equal to the sum of the second volumetric flow rate output through the output end and the bypass gas output flow rate output through the bypass end.

4. The particle differential electromigration analyzer as claimed in claim 1, wherein the first volumetric flow rate and the fourth volumetric flow rate are between 2 and 20 L / min, the second volumetric flow rate and the third volumetric flow rate are between 0.2 and 4 L / min, and the sum of the first volumetric flow rate and the second volumetric flow rate is between 2.2 and 25 L / min.

5. The particle differential electromigration analyzer as claimed in claim 4, wherein the first volumetric flow rate and the fourth volumetric flow rate are between 12 and 18 L / min, the second volumetric flow rate and the third volumetric flow rate are between 0.8 and 2.5 L / min, and the sum of the first volumetric flow rate and the second volumetric flow rate is between 12 and 18 L / min.

6. The particle differential electromigration analyzer as claimed in claim 1, wherein the residual gas discharge end further includes an orifice plate and is connected to a vacuum pump, the vacuum pump and the orifice plate controlling the extraction of the remaining mixed aerogel at the fourth volumetric flow rate.

7. The particle differential electromigration analyzer as described in claim 6, wherein the vacuum pump is electrically connected to the control device, and when the orifice plate is replaced, the control device controls the change of the first volumetric flow rate according to the fourth volumetric flow rate changed by the vacuum pump.

8. The particle differential electromigration analyzer as claimed in claim 1, wherein the residual gas discharge end further includes a second mass flow control device, a second temperature sensor and a second pressure sensor, the second mass flow control device, the second temperature sensor and the second pressure sensor being electrically connected to the control device, the second mass flow control device controlling the discharge of the remaining mixed aerogel at a second mass flow rate, the second temperature sensor and the second pressure sensor sensing the temperature and pressure of the mixed aerogel and generating second temperature information and second pressure information to the control device, the control device adjusting the second mass flow rate to the fourth volumetric flow rate based on the second temperature information and the second pressure information.

9. The particle differential electromigration analyzer as described in claim 8, wherein when the control device controls the second mass flow control device to change the fourth volumetric flow rate, it simultaneously controls the mass flow control device to change the first volumetric flow rate.

10. The particle differential electromigration analyzer as claimed in claim 1, wherein the particle separation chamber comprises a plurality of particle collection tanks, wherein a plurality of particles in the aerogel are separated according to their particle size based on the electric field and the first volumetric flow rate, and are guided into the particle collection tanks.

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