Station and method for measuring particle contamination of a transport cartridge for transporting and storing

Abstract

A measuring station (1) for measuring particle contamination in a transport capsule for atmospheric transport and storage of semiconductor wafers, and comprising a particle counter (5) and an interface (6) designed to be coupled to a housing (2) of the transport capsule instead of a door (3), the interface (6) comprising a sampling hole (7) in fluid connection with the particle counter (5), the measuring station (1) further comprises a clean gas injection device (15) comprising at least one injection line (16) comprising at least one nozzle (17) designed to be fluidly connected to the vent (4) of the transport compartment coupled to the interface (6), the nozzle (17) being designed to be fluidly connected to the vent (4) of the transport compartment coupled to the interface (6), and the nozzle (17) being designed to be fluidly connected to the vent (4) of the transport compartment coupled to the interface (6). In order to inject a cleaning gas into the transport compartment from the outside of the transport compartment via at least one vent (4) of the transport compartment.

Description

Technical Field

[0001] The invention relates to a measuring station for measuring particle contamination of a transport enclosure for transporting and storing semiconductor wafers at atmospheric pressure and to a corresponding measuring method. Background Art

[0002] In the semiconductor manufacturing industry, shipping pods, particularly standardized front opening pods (FOUP) wafer shipping and storage pods, are used to transport silicon wafers from one piece of equipment to another, or to store wafers between two manufacturing stages.

[0003] These shipping pods are made of materials such as polycarbonate, which in some cases can accumulate contaminants, particularly organic, amine or acidic contaminants. The silicon wafers spend a long time inside these closed pods. Therefore, controlling contamination, particularly particulate contamination, in these containers is critical.

[0004] In order to determine when the pod needs cleaning, a measuring device is known from document WO 2014083151, which comprises a particle detector and an interface designed to be connected to the housing of the transport pod in place of a door. The interface measuring head has a sampling hole connected to the particle detector and a nozzle, which injects a purge gas from the inside of the pod into the walls of the housing in order to separate, sample and count the particles adhering to these walls.

[0005] The device can determine the degree of contamination on the inner surfaces of a transport pod where particles may fall from the walls onto substrates / wafers contained within the transport pod while the pod is being handled.

[0006] However, there is another element of monitoring the transport pod that becomes very important.

[0007] Initially, the vents of the transport pods equipped with particle filters only needed to equalize the pressure between the inside and outside of the pod, in particular to prevent air flow (e.g. clean room air entering the pod when the door is opened), but also to avoid mechanical stress caused by a pressure drop inside the pod, which could become a source of contamination.

[0008] However, currently these vents are used as inlets for nitrogen or ultra-dry air, which is injected into the pod to purge the interior and limit the presence of gaseous contaminants (gas phase molecular contaminants or AMCs) to ensure acceptable production yields. Some of these vents are even more complex, adding many elements in addition to the filter, such as check valves, diffusers, etc., which may generate particles and clog the filter, or they themselves may also become a source of leaks.

[0009] One consequence of this is that a faulty or inadequate vent filter immediately creates a high risk that the purge gas injected into the pod will contaminate the silicon wafers contained within the pod. The widespread practice of purging shipping pods through the vents means that particle filters are becoming a major source of contamination risk in shipping pods.

[0010] However, existing solutions for monitoring particle contamination in transport pods are not suitable for determining the level of contamination in vent filters.

[0011] In fact, using ultra-clean water to loosen particles and counting the particles with a liquid particle counter to determine the concentration does not allow for rapid testing, especially for monitoring the particle concentration of a filter.

[0012] As described in WO2014083151, clean air is injected into the transport pod to loosen the particles and count them, which also does not enable monitoring of the filters in the pod.

[0013] Another measurement method is to use a test silicon wafer that has been previously measured for particles using a wafer-specific particle measurement device. The measured test wafer is placed in a transport pod that is connected to a purge station to inject purge gas through the pod's port. The test silicon wafer is then removed from the pod, the particles deposited on the wafer are counted using a measurement device, and the results are compared with the initial measurement. This measurement method is relatively slow and costly, and is not efficient enough for automated production control. In addition, wafer particle measurement equipment is not always available because process tool qualification testing for production is a priority. Summary of the invention

[0014] One of the objects of the present invention is therefore to propose a measuring station and a corresponding measuring method making it possible to measure in real time the particle contamination level of a particle filter of a vent of an atmospheric transport capsule directly in the manufacturing plant.

[0015] To this end, the present invention relates to a measuring station for measuring particle contamination in a transport pod (in particular a FOUP pod), which is used for transporting and storing semiconductor wafers at normal pressure, the transport pod comprising an outer shell and a removable door capable of closing the outer shell, the outer shell having at least one vent provided with a particle filter, for example one to four vents, the measuring station comprising a particle counter and an interface designed to be connected to the outer shell in place of the door, the interface comprising a sampling hole fluidly connected to the particle counter.

[0016] The measuring station also includes a clean gas injection device, which includes at least one injection pipeline, and the injection line includes at least one nozzle, which is designed to be fluidically connected to the ventilation port of the transport box connected to the interface so as to inject clean gas into the transport box from the outside of the transport box through at least one ventilation port of the transport box.

[0017] Injecting clean gas into the vents simulates production risk conditions associated with purging the transport pod through one or more vents. If there is a particle contamination problem with the particle filter in the vent, this can be detected using particles sampled from inside the transport pod through the sampling holes and measured with a particle counter. The test conditions are the same as production conditions. Real-time particle counting also maintains productivity.

[0018] The measuring station may also have one or more of the features described below, which may be employed alone or in combination.

[0019] The sampling orifice is, for example, arranged in a measuring head protruding from a base of the interface.

[0020] The measuring station may comprise a vacuum pump arranged downstream of the particle counter in the gas pumping direction.

[0021] The particle counter is, for example, an aerosol particle counter. The particle counter is, for example, optical. The pumping flow rate of the vacuum pump is, for example, 30 l / min (1.8 m 3 / h or 0.0005m 3 / s).

[0022] In order to connect the transport pod to the measuring station and remove the door therefrom, the measuring station may include a chamber for receiving the interface, the chamber having a lateral entrance and a loading port arranged below the entrance. The loading port may be connected to the housing and the door of the transport pod so as to move the door into the chamber and communicate the interior of the housing with the interior of the chamber.

[0023] For example, the clean gas injection device comprises the same number of nozzles as the number of vents on the transport pod. According to another example, the clean gas injection device comprises at least one plug, which is designed to close the vents, for example so that all vents are engaged with the nozzle or the plug. Alternatively, some vents may be left unengaged.

[0024] The at least one nozzle for example comprises sealing means to provide a tight connection with the vent.

[0025] The cleaning gas injection device may comprise an actuator designed to push one or more nozzles or one or more plugs against the corresponding vents, as applicable.

[0026] The clean gas injection device may comprise at least one pressure sensor designed to measure the pressure in the injection line.

[0027] The clean gas injection device may further include at least one flow control device, so as to control the injection of different gas flow rates into the injection pipeline, for example, at 30 l / min (0.0005 m 3 / s) to 100l / min (0.00167m 3 / s), for example, an average of 50 l / min (0.00083 m 3 / s) and up to 100l / min (0.00167m 3 / s).

[0028] For example, each injection line has a pressure sensor and a flow control device.

[0029] The present invention also relates to a method for measuring particle contamination of a transport box, which is used to transport and store semiconductor wafers at normal pressure. The method is implemented in a measuring station as described above, wherein a clean gas is injected into the transport box from the outside of the transport box through at least one ventilation port of the transport box, and the particles of the gas sample collected through the sampling hole of the interface during the injection process are counted.

[0030] The measuring method may also have one or more of the features described below, which may be employed alone or in combination.

[0031] According to an exemplary embodiment, the cleaning gas flow rate injected by the at least one nozzle is greater than the sampling gas flow rate. For example, the cleaning gas flow rate injected into the at least one nozzle is greater than 6 l / min (0.0001 m 3 / s), for example, greater than 30l / min (1.8m 3 / h or 0.0005m 3 / s), for example, greater than 50l / min (3m 3 / h or 0.000833333m 3 / s), for example 80l / min (4.8m 3 / h or 0.00133333m 3 / s). By injecting the clean gas at a flow rate greater than the sample gas flow rate and greater than the flow rate normally used to purge the transport pod under production conditions, the transport pod can be subjected to slightly greater stress than during the purge operation. This helps remove particles from the particle filter for counting.

[0032] The cleaning gas is, for example, nitrogen or compressed air of quality grade 1 / 1 / 1 of ISO8573-1:

[0033]

[0034] According to an exemplary embodiment, in order to measure the particle contamination of a transport pod having multiple vents, all vents of the transport pod are injected simultaneously and the number of particles is counted during the injection. This method enables the overall cleanliness level of the particle filter in the transport pod to be determined.

[0035] According to another exemplary embodiment, to measure particle contamination of a transport pod having multiple vents, the vents are injected sequentially, i.e., one port at a time or in groups of two or more ports simultaneously, and the number of particles is counted during each injection. Sorting helps to find problematic filters.

[0036] According to an exemplary embodiment, a fault in a vent, in particular a vent with an abnormally high particle count, is identified by measuring the pressure in the injection line via a pressure sensor during injection and comparing said pressure with a reference value, for example a reference value obtained in an injection line without a fault, in order to determine in particular whether this is due to a fault in the particle filter.

[0037] A difference between the measured pressure and the reference value may indicate a malfunction in the vent. If the measured pressure is lower than the reference value, this may indicate a defective particle filter in the vent or a leak in an element in the clean gas injection device. If the measured pressure is higher than the reference value, this may indicate a malfunction in the valve in the vent. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Other advantages and features are contained in the description of non-limiting exemplary embodiments of the invention and in the accompanying drawings, in which:

[0039] [ Figure 1 ] Figure 1 is a perspective view of a particle contamination measurement station coupled to a transport pod.

[0040] [ Figure 2 ] Figure 2 An enlarged view of the housing of a transport pod coupled to a measurement station is shown.

[0041] [ Figure 3 ] Figure 3 Schematic diagram (bottom view) of the clean gas injection device of the measuring station and the various elements of the transport capsule.

[0042] [ Figure 4 ] Figure 4 One example of a shipping pod vent is shown in assembled and disassembled states.

[0043] [ Figure 5a ] Figure 5a This is a schematic diagram of the measurement station and the transport capsule.

[0044] [ Figure 5b ] Figure 5b is with Figure 5a Similar and continuing views, wherein the load port of the measurement station is coupled to the door of the transport pod.

[0045] [ Figure 5c ] Figure 5c is with Figure 5b Similar and continuous views with the load port door and pod door moved away from the chamber entrance of the measurement station.

[0046] [ Figure 5d ] Figure 5d is with Figure 5c Similar and continuing views with the interface coupled to the housing of the transport pod.

[0047] [ Figure 6 ] Figure 6 It is a graph showing the measured pressure change over time when there is a fault in the injection line of the clean gas injection device during the injection process (solid line) and when there is no fault (dashed line).

[0048] In these figures, the same elements are denoted by the same reference numerals. DETAILED DESCRIPTION

[0049] The following embodiments are merely examples. Although the description relates to one or more embodiments, this does not necessarily mean that each reference numeral refers to the same embodiment, or that these features apply to only one embodiment. Individual features of different embodiments may also be combined or exchanged to provide other embodiments.

[0050] Figure 1 A measurement station 1 for measuring particle contamination in wafer handling and storage pods of a front opening pod (FOUP) is shown.

[0051] These transport pods have a closed internal atmosphere of air or nitrogen at atmospheric pressure, ie, a pressure roughly equivalent to, but separate from, the operating environment of the clean room.

[0052] like Figure 2 and 5a As shown, the transport pod includes an outer shell 2 and a removable door 3 that can close the outer shell 2, and the size of the door 3 is designed so that the wafer can be inserted into and removed from the pod. The outer shell 2 and the door 3 are made of a material such as polycarbonate. The inner side wall, the bottom wall and the door 3 are provided with grooves for holding the wafer. The pod is relatively tight, but the sealing degree is designed so that slight leakage may occur through the gasket arranged between the outer shell 2 and the door 3.

[0053] The housing 2 in the FOUP transport pod includes at least one vent 4, for example one to four vents 4, each of which is equipped with a particle filter 4a to prevent particles from entering the transport pod ( Figure 3 and 4 The vent 4 is arranged at the bottom of the housing 2, and in particular, the vent 4 balances the pressure between the inside and the outside of the transport box to prevent air flow when the door is opened.

[0054] The vent 4 can only be formed by an orifice provided with a particle filter 4a, and gas can flow in and out through each vent 4 of the pod simultaneously and indifferently. Other vents 4 can have an inlet or outlet check valve 4b, which is arranged in a corresponding orifice upstream or downstream of the particle filter 4a. If the gas inside the transport pod is excessive relative to the external atmospheric pressure, the outlet check valve opens, and if the pod is negative pressure inside, the inlet check valve opens. The vent 4 can also include other elements, such as a gasket, a support element 4c, a diffuser 4d or a grommet 4e.

[0055] like Figure 5a As shown, the measuring station 1 comprises a particle counter 5 and an interface 6 which is designed to be coupled to the housing 2 of a transport capsule coupled to the measuring station 1 instead of the door 3 .

[0056] The interface 6 comprises a sampling port 7 which is fluidically connected via a sampling line to the particle counter 5. The sampling port 7 is for example arranged in a measuring head 8 extending from the base of the interface 6, but in this case the substrate is removed from the transport pod before taking measurements.

[0057] The measuring station 1 may further comprise a vacuum pump 19 arranged downstream of the particle counter 5 in the gas pumping direction.

[0058] A gas sample is collected by suction from a measuring volume of the housing 2 connected to the interface 6 via a sampling opening 7. The number of particles contained in the collected gas sample is determined by a particle counter 5. The particle counter 5 is, for example, an aerosol particle counter, i.e., provides quantitative information about suspended particles in a gaseous environment. The particle counter is, for example, optical, for example based on laser technology. The pumping rate of the vacuum pump 19 is, for example, 30 l / min (1.8 m 3 / h or 0.0005m 3 / s).

[0059] In order to couple the transport pod to the measuring station 1 and remove the door 3 therefrom, the measuring station 1 can comprise a chamber 9, in particular a chamber 9 with a controlled environment, in which the interface 6 is located in particular. The chamber 9 is, for example, a clean room at atmospheric pressure. For example, the chamber is ISO 3 certified according to the ISO 146644-1 "microenvironment" standard. For this purpose, the chamber 9 can comprise a laminar flow filter unit 10.

[0060] According to an exemplary embodiment, chamber 9 has a side entrance 11 and a loading port 12 located below entrance 11. Loading port 12 can be coupled to housing 2 and door 3 of the transport pod to move door 3 into chamber 9 and communicate the interior of housing 2 with the interior of chamber 9.

[0061] To this end, the loading port 12 comprises a platform 13 for receiving and positioning the transport pod. The platform 13 may comprise a presence sensor designed to check whether the model of the transport pod is compatible with the measuring station 1 receiving the pod. Furthermore, in order to couple with the housing 2, the platform 13 of the loading port 12 comprises a fixture for clamping the housing 2 and then translating it against the inlet 11 of the chamber 9 ( Figure 5a According to another example (not shown), the loading port 12 comprises a displacement device designed to move the fixing device from the loading port 12 towards the pod.

[0062] The load port 12 also comprises a load port door 14. The load port door 14 has substantially the same dimensions as the door 3 of the transport pod. The load port door 14 in particular closes the entrance 11 to the chamber 9 when no transport pod is present. Bolt actuation means for locking and unlocking the locking member of the door 3 are also provided.

[0063] Known locking means for the door 3 are, for example, latches provided by the door 3 which are actuated by radial or lateral sliding and which engage in the housing 2 of the transport capsule when the transport capsule is closed.

[0064] Once the locking member has been released, the bolt actuation device reversibly secures the door 3 to the load port door 14. The doors 3, 14 can then be moved out from the front area of ​​the entrance 11 into the chamber 9 as a single unit via the actuation mechanism of the load port door 14.

[0065] The interface 6 can then be coupled to the housing 2 in place of the door 3, thereby placing the sampling aperture 7 connected to the particle counter 5 in fluid communication with the interior volume of the housing 2. The housing 2 and the interface 6 then form a "transport pod".

[0066] The measuring station 1 also comprises a clean gas injection device 15 having at least one injection line 16 .

[0067] The injection line 16 comprises at least one nozzle 17 designed to be fluidically connected to the vent 4 of the transport pod coupled to the interface 6 to inject the clean gas from outside the transport pod through the vent 4 of the transport pod into the transport pod.

[0068] For example, the nozzle 17 protrudes from the platform 13 at a position on the platform 13 so as to be positioned opposite the vent 4 of the transport capsule once the housing 2 has been fixed to the interface 6. The nozzle 17 is for example designed to engage in the orifice of the vent 4 of the transport capsule.

[0069] The cleaning gas injection device 15 comprises, for example, as many nozzles 17 as the number of ventilation openings 4 on the transport capsule.

[0070] According to another example, the cleaning gas injection device 15 comprises at least one plug designed to close the ventilation openings 4 , for example so that all ventilation openings 4 are engaged with the nozzle 17 or the plug.

[0071] Alternatively, some ventilation openings 4 may be left.

[0072] The nozzle 17 includes, for example, respective sealing means to provide a tight connection with the vent 4. The sealing means is, for example, made of an elastic material, such as silicone. The means is, for example, a suction cup, an annular gasket, a lip seal, or a bellows surrounding the orifice of the nozzle 17. In another example, the sealing means is made of a rigid material, such as PEEK, and sealing can be achieved by compressing the sealing means.

[0073] The cleaning gas injection device 15 may comprise an actuator designed to push one or more nozzles 17 or one or more plugs against the corresponding ventilation opening 4, as applicable.

[0074] One or more injection lines 16 connecting the nozzles 17 are connected to one or more gas supply devices 18, such as gas outlets (also called "facilities") available on site.

[0075] The one or more injection lines 16 may also be equipped with a particle filter 20 to filter any contaminant particles ( Figure 3 ).

[0076] The cleaning gas is, for example, nitrogen, or pure dry or ultra-dry air.

[0077] The injection flow rate of the cleaning gas injected into each nozzle 17 is, for example, 6 l / min (0.0001 m 3 / s) to 30l / min (1.8m 3 / h or 0.0005m 3 / s).

[0078] The clean gas injection device 15 may also include at least one pressure sensor 21, which is designed to measure the pressure in the injection pipeline 16 ( Figure 3). Thus, a fault in the vent 4, for example a fault in the particle filter 4a, can be identified by measuring the pressure in the injection line 16 and comparing this pressure with a reference value.

[0079] The cleaning gas injection device 15 may further include at least one flow control device 22, so as to be able to control the injection of different gas flow rates into the injection pipeline 16, for example, at 30 l / min (0.0005 m 3 / s) to 100l / min (0.00167m 3 / s), for example, an average of 50 l / min (0.00083 m 3 / s) and up to 100l / min (0.00167m 3 / s).

[0080] For example, there is one pressure sensor 21 and one flow control device 22 for each injection line 16. The pressure sensor 21 is arranged downstream of the flow control device 22 and the particle filter 20 in the clean gas flow direction in the injection line 16. The sensor is also advantageously positioned as close as possible to the vent 4 to improve the measurement sensitivity.

[0081] The control means of the transport pod model, the bolt actuation means, the actuation mechanism of the load port door 14 and the cleaning gas injection means 15 can be controlled by a processing unit 23 (e.g. a computer or a controller) of the measuring station 1. The processing unit 23 can be connected to a user interface 24, which in particular comprises a screen and a keyboard, for example. Figure 1 shown.

[0082] The measuring station 1 also comprises, for example, an electrical cabinet 25 for supplying power to some or all of the electrical components of the measuring station and for housing these electrical components. The electrical cabinet 25 is advantageously offset laterally from the chamber 9 so as to be away from the laminar flow of filtered air, thereby preventing the chamber 9 from being contaminated by the various components housed in the electrical cabinet 25.

[0083] The method for measuring particle contamination of a transport pod for transporting and storing semiconductor wafers at atmospheric pressure, which is implemented in a measuring station 1, comprises the steps described below.

[0084] When the measuring station 1 is in the idle position, the interface 6 is arranged in the chamber 9, wherein the inlet 11 is closed by the load port door 14 ( Figure 5a ).

[0085] When an operator or robot places the transport pod on the platform 13 of the loading port 12, the loading port 12 then locates and checks the transport pod model, then clamps the pod's shell 2 and moves it toward the entrance 11 of the chamber 9 ( Figure 5a , as shown in Figure 1 (arrow D1).

[0086] The latch actuator of the load port door 14 then releases the locking member of the door 3 and rigidly connects the door 3 to the load port door 14 ( Figure 5b ).

[0087] The doors 3, 14 are then moved away from the entrance 11 into the chamber 9 ( Figure 5b ), so that the internal volume of the housing 2 is connected to the internal volume of the chamber 9.

[0088] Then, the interface 6 is moved toward the housing 2 and connected to the housing 2 in place of the door 3. In the connected state, the measuring head 8 is immobilized in the measuring volume defined by the interface 6 and the connected housing 2.

[0089] Then, clean gas is injected into the transport box from outside the transport box through one or more ventilation ports 4 of the transport box, and the particles of the gas sample collected through the sampling hole 7 of the interface 6 during the injection are counted (in real time / simultaneously). The gas sample is collected from the measurement volume by suction through the sampling line. The number of particles contained in the collected gas sample is continuously determined by the particle counter 5.

[0090] Injecting clean gas into the vent 4 simulates production risk conditions associated with purging the transport pod via the vent 4. If there is a particle contamination problem with the particle filter 4a in the vent 4, this can be detected by measuring with the particle counter 5 using particles sampled from inside the transport pod. The test conditions are the same as production conditions. Real-time particle counting also allows maintaining productivity.

[0091] According to an exemplary embodiment, the cleaning gas flow rate injected by the at least one nozzle 17 is greater than the sampling gas flow rate. For example, the cleaning gas flow rate injected by the at least one nozzle 17 is greater than 6 l / min (0.0001 m 3 / s), for example, greater than 30l / min (1.8m 3 / h or 0.0005m 3 / s), for example, greater than 50l / min (3m 3 / h or 0.000833333m 3 / s), for example 80l / min (4.8m 3 / h or 0.00133333m 3 By injecting the clean gas at a flow rate greater than the sample gas flow rate and greater than the flow rate normally used to purge the transport pod under production conditions, the transport pod can be subjected to slightly greater stress than during the purge operation. This helps remove particles from the particle filter 4a for counting.

[0092] For each nozzle 17, the injection time is, for example, one minute.

[0093] According to an exemplary embodiment, all ventilation openings 4 of the transport pod are injected simultaneously and the number of particles is counted during this injection. This method enables the overall cleanliness level of the particle filter 4a in the transport pod to be determined.

[0094] According to another exemplary embodiment, the vents 4 are injected sequentially, either one port at a time or in groups of two or more ports at the same time, and the number of particles is counted during each injection. The sorting enables the problematic vents 4 to be found.

[0095] According to an exemplary embodiment, a fault in the vent 4, in particular a vent with an abnormally high particle count, is identified by measuring the pressure in the injection line 16 during injection via the pressure sensor 21 and comparing said pressure with a reference value (e.g. a reference value obtained in an injection line 16 without a fault determined during commissioning or by calculation), in order to determine in particular whether this is due to a fault in the particle filter 4a.

[0096] The difference between the measured pressure and the reference value may indicate a malfunction in the vent 4. If the measured pressure is lower than the reference value, for example, 20% lower than the reference value, it may indicate that the particle filter 4a in the vent 4 is damaged, or that there is a leak in an element in the clean gas injection device 15. If the measured pressure is higher than the reference value, it may indicate that the valve 4b in the vent 4 is malfunctioning.

[0097] In fact, the particle filter 4a "brakes" the clean gas as it is injected into the vent 4 via the nozzle 17, resulting in a steady increase in pressure during steady-state injection. If the particle filter 4a is damaged, incorrectly positioned or missing, the pressure stabilizes at a lower value.

[0098] Figure 6 This is illustrated in the graph in , which shows the relationship between the pressure measured in a faulty injection line 16 (solid line) and a non-faulty injection line 16 (dashed line) over time during an injection process starting from t0.

[0099] The graph shows that the pressure measured in the filling line 16 is significantly lower than the reference value of a non-faulty filling line 16 , at least 20% lower, in this case almost 50% lower, which may indicate a fault in the particle filter 4 a of the ventilation opening 4 .

[0100] When the measurements are completed, the interface 6 is removed from the housing 2 and the transport capsule is closed and released to be sent for cleaning, or to continue with shipping or storage operations, depending on its cleanliness.

Claims

1. A measuring station (1) for measuring particle contamination in a transport box, the transport box being used for transporting and storing semiconductor wafers at normal pressure, the transport box comprising a housing (2) and a detachable door (3) capable of closing the housing (2), the housing (2) having at least one ventilation opening (4), the ventilation opening (4) being provided with a particle filter (4a), the measuring station (1) comprising a particle counter (5) and an interface (6), the interface (6) being designed to be connected to the housing (2) in place of the door (3), the interface (6) comprising a sampling hole (7) fluidically connected to the particle counter (5), characterized in that The measuring station (1) also includes a clean gas injection device (15), which includes at least one injection line (16), and the injection line (16) includes at least one nozzle (17). The nozzle (17) is designed to be fluidically connected to the ventilation port (4) of the transport cabin connected to the interface (6) so as to inject clean gas into the transport cabin from the outside of the transport cabin through the at least one ventilation port (4) of the transport cabin.

2. The measuring station (1) according to claim 1, characterized in that The clean gas injection device (15) comprises at least one pressure sensor (21) designed to measure the pressure in the injection line (16).

3. A method for measuring particle contamination of a transport pod for transporting and storing semiconductor wafers at atmospheric pressure, the method being implemented in a measuring station (1) according to any one of the preceding claims, characterized in that Clean gas is injected into the transport box from the outside of the transport box through the at least one ventilation port (4) of the transport box, and particles of the gas sample collected through the sampling hole (7) of the interface (6) during the injection process are counted.

4. The measuring method according to the preceding claim, characterized in that The flow rate of the cleaning gas injected by the at least one nozzle (17) is greater than the flow rate of the sampling gas.

5. The measuring method according to the preceding claim, characterized in that The flow rate of the cleaning gas injected into the at least one nozzle (17) is greater than 0.0001 m 3 / s, for example, greater than 0.0005m 3 / s.

6. The measuring method according to any one of claims 3 to 5, characterized in that: The cleaning gas is nitrogen or pure dry air.

7. The measuring method according to any one of claims 3 to 6, for measuring particle contamination of a transport capsule having a plurality of ventilation openings (4), characterized in that: All vents (4) of the transport pod are filled simultaneously and the number of particles is counted during the filling.

8. The measuring method according to any one of claims 3 to 6, for measuring particle contamination of a transport capsule having a plurality of ventilation openings (4), characterized in that: The vents (4) are injected sequentially and the number of particles is counted during each injection.

9. The measuring method according to any one of claims 3 to 8, characterized in that: By measuring the pressure in the injection line (16) and comparing the pressure with a reference value, a fault in the vent (4) is identified.

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