Equipment and manufacturing process

Abstract

Manufacturing equipment (1), in particular for semiconductor components, LEDs or flat panel displays, comprising at least two process chambers (2a, 2b, 2c, ...2n) and as many turbomolecular vacuum pumps (3a, 3b, 3c, ...3n) fluidly connected to a respective process chamber (2a, 2b, 2c, …2n) via respective first isolation valves (4a, 4b, 4c, …4n) characterized in that it further comprises: - at least one set of two primary process vacuum pumps (5a, 5b), the inlets of said primary process vacuum pumps (5a, 5b) of the set being fluidly connected in parallel via respective second isolation valves (6a, 6b) to a common pipeline (7) fluidly connected in parallel to the outlets of the turbomolecular vacuum pumps (3a, 3b, 3c, …3n), all the outlets of the turbomolecular vacuum pumps (3a, 3b, 3c, …3n) being fluidly connected to the two primary process vacuum pumps (5a, 5b) of at least one set, and - a primary service vacuum pump (8) fluidically connected in parallel to the process chambers (2a, 2b, 2c, ...2n) of said equipment (1) via respective third isolation valves (9a, 9b, 9c, ...9n).Abbreviation figure: Figure 1.

Description

Title of the invention: Equipment and manufacturing process Technical field of the invention

[0001] The present invention relates to manufacturing equipment, particularly for manufacturing semiconductor components, LEDs (Light-Emitting Diodes), or flat panel displays, said equipment comprising at least two process chambers and as many turbomolecular vacuum pumps fluidly connected to a respective process chamber. The present invention also relates to a manufacturing process implemented in such equipment. Technical background

[0002] Vacuum pumps are used in particular in equipment for manufacturing semiconductors, LEDs or flat screens, requiring a pressure lower than atmospheric pressure.

[0003] Certain process chambers of these manufacturing equipment are equipped with turbomolecular vacuum pumps fluidly connected to a respective primary vacuum pump enabling the desired low production pressures to be achieved.

[0004] To increase throughput, this equipment can be multi-chamber (called "clusters"). This equipment generally comprises at least four process chambers and up to twelve chambers for the latest generation of equipment. Each chamber of the equipment is fluidly connected to a turbomolecular vacuum pump, which is itself fluidly connected to a primary vacuum pump, so that each piece of equipment is equipped with as many turbomolecular vacuum pumps and primary vacuum pumps as there are process chambers.

[0005] Since primary vacuum pumps are bulky, noisy, and hot, they can be relocated, particularly in semiconductor manufacturing plants, to a floor below the one housing the process chambers. The fluid connections from the primary vacuum pumps to the turbomolecular vacuum pumps between the floors are made using respective pipes, sometimes heated to prevent the formation of reaction byproducts that could reduce pumping performance or even damage the vacuum pumps.

[0006] Today, efforts are being made to simplify these multi-chamber manufacturing equipment. Summary of the invention

[0007] One object of the present invention is to reduce the cost of investment and use of manufacturing equipment while maintaining high reliability and similar pumping performance.

[0008] To this end, the invention relates to manufacturing equipment, in particular for semiconductor components, LEDs or flat screens, comprising at least two process chambers and as many turbomolecular vacuum pumps fluidly connected to a respective process chamber via respective first isolation valves, characterized in that it further comprises: - at least one set of two primary process vacuum pumps, the inlets of said primary process vacuum pumps of the set being fluidly connected in parallel via respective second isolation valves to a common pipeline fluidly connected in parallel to the outlets of the turbomolecular vacuum pumps, all outlets of the turbomolecular vacuum pumps being fluidly connected to the two primary process vacuum pumps of at least one set, and - a primary service vacuum pump fluidly connected in parallel to the process chambers of said equipment via respective third isolation valves.

[0009] This sharing of primary process vacuum pumps is possible, firstly, because, for pressures below a certain pressure threshold, a change in discharge pressure does not cause a change in the suction pressure of the turbomolecular vacuum pump. In other words, as long as the discharge pressure of the turbomolecular vacuum pump is below the pressure threshold, there is no impact upstream of the turbomolecular vacuum pump. The same pumping performance is expected for the turbomolecular vacuum pumps as if they had a dedicated primary pump.

[0010] The two primary process vacuum pumps operating simultaneously, each configured to maintain the discharge pressures of the turbomolecular vacuum pumps below the pressure threshold, also ensure that the vacuum is maintained in the process chambers during manufacturing steps in the event of a failure of one of the process vacuum pumps, at least until the ongoing manufacturing steps are completed. This prevents damage to the substrates being manufactured in the process chambers.

[0011] The manufacturing equipment is thus less expensive to invest in and reduces the footprint (saving 40% to 50%) because it includes fewer primary vacuum pumps and reduces the number of pipes connecting the turbomolecular vacuum pumps from the cleanroom to the basement, as well as the number of electrical (boxes and electrical cables) and fluid connections required for the operation of the primary vacuum pumps. It is also less expensive to operate due to reduced electricity consumption (saving 30% to 60%), reduced purge gas consumption (saving at least 50%), and Cooling heat transfer fluid (50% energy saving) is required for the operation of each primary vacuum pump. The equipment is also more reliable than prior art equipment because it has a backup primary vacuum pump in case of failure of a primary process vacuum pump, thus preventing the loss of substrate during production.

[0012] The equipment may further include one or more of the features described below, taken alone or in combination.

[0013] The primary process vacuum pumps of the assembly can be identical.

[0014] Each of the two primary process vacuum pumps is configured in particular to be able to lower the discharge pressure of the turbomolecular vacuum pumps to which they are fluidly connected, to a pressure below a pressure threshold below which a variation in discharge pressure does not cause a variation in suction pressure of the turbomolecular vacuum pump, including when a gas flow is injected at a predetermined maximum value into all process chambers located upstream of said turbomolecular vacuum pumps.

[0015] A set of two primary process vacuum pumps is for example fluidly connected to two, three, four, five or six turbomolecular vacuum pumps.

[0016] The process chambers, turbomolecular vacuum pumps, first isolation valves and third isolation valves are arranged in a cleanroom and the primary process vacuum pumps, second isolation valves and the primary service vacuum pump can be arranged on a floor located below the cleanroom.

[0017] A service pipe fluidly connecting the pipes of the third isolation valves to the primary service vacuum pump has, for example, a diameter of 40 mm or 50 mm.

[0018] The common pipe has, for example, a diameter of 160 mm.

[0019] The equipment may include: - at least two airlocks, each configured to receive a substrate in one chamber of the airlock and lower the atmospheric pressure in the chamber to a predetermined transfer pressure and / or to receive a substrate at a predetermined transfer pressure in one chamber of the airlock and raise the pressure in the chamber to atmospheric pressure, - a transfer chamber configured to transfer substrates at the predetermined transfer pressure from the airlock to a process chamber and from a process chamber to an airlock.

[0020] The equipment may include a control unit configured to control the opening and closing of the first isolation valves, the second isolation valves and the third isolation valves.

[0021] The equipment can be configured to implement manufacturing steps for which a maximum value of the gas flow injected into each process chamber is less than 3,000 sccm (5.07 Pa.m3 / s).

[0022] The equipment can be configured to perform etching or vacuum deposition of thin films.

[0023] The invention further relates to a manufacturing process characterized in that it is implemented in manufacturing equipment as described above, in which, during the substrate manufacturing steps: - in a fault-free situation, the second isolation valves are open so that at least two primary process vacuum pumps simultaneously draw from the outlet of the turbomolecular vacuum pumps to which they are fluidly connected, - in the event of failure of one of the primary process vacuum pumps, the second isolation valve located upstream of the failed process vacuum pump closes, isolating the failed process vacuum pump, the other primary process vacuum pump alone ensuring the pumping at the discharge of the turbomolecular vacuum pumps.

[0024] Each of the two primary process vacuum pumps lowers the discharge pressure of the turbomolecular vacuum pumps to which they are fluidly connected, to a pressure below a pressure threshold below which a change in discharge pressure does not cause a change in suction pressure of the turbomolecular vacuum pump, including when a gas flow is injected at a predetermined maximum value into all process chambers located upstream of said turbomolecular vacuum pumps. Brief description of the figures

[0025] Other advantages and features will become apparent from the following description of a particular, but by no means limiting, embodiment of the invention, as well as from the accompanying drawings in which:

[0026] [Fig-1] Fig. 1 shows a schematic top view of a piece of equipment semiconductor component manufacturing.

[0027] [Fig.2] Fig.2 shows a schematic view of a manufacturing equipment, such as than that of [Fig.1].

[0028] [Fig. 3] Figure 3 shows a graph of the suction pressure of a pump Turbomolecular vacuum (in mbar: 102 Pa) as a function of discharge pressure of the turbomolecular vacuum pump (in mbar: 102 Pa) for different nitrogen flux values: 50 sccm, 100 sccm, 200 sccm, 500 sccm, 1000 sccm, 2000 sccm and 5000 sccm.

[0029] [Fig.4] Figure [Fig.4] shows a histogram of the discharge pressure: - turbomolecular vacuum pumps (in mbar: 102 Pa) during an etching step (the turbomolecular vacuum pumps being said to be "active") and - standby turbomolecular vacuum pumps (with little or no gas flow injected into the process chamber to be pumped), depending on the number of active turbomolecular vacuum pumps, six-process chamber equipment and a set of two associated primary process vacuum pumps.

[0030] [Fig.5] [Fig.5] shows a view similar to [Fig.1] for another example of manufacturing equipment embodiment.

[0031] In these figures, identical or similar elements bear the same reference numbers.

[0032] Only the elements necessary for understanding the invention are represented. Detailed description

[0033] The following embodiments are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Simple features of different embodiments can also be combined or interchanged to provide other embodiments, without departing from the scope of the invention as defined by the claims.

[0034] The term "upstream" refers to an element that is placed before another with respect to the direction of flow of the pumped gases. Conversely, the term "downstream" refers to an element placed after another with respect to the direction of flow of the pumped gases.

[0035] The manufacture of certain devices, in particular the manufacture of semiconductor components, LEDs or flat screens, requires the carrying out of different physico-chemical processes on substrates such as wafers, generally silicon in the semiconductor component manufacturing industry, called "wafers" in English.

[0036] These processes are carried out in automated manufacturing equipment 1, generally arranged in controlled cleanroom environments.

[0037] The multi-chamber manufacturing equipment 1 (called "cluster" in English) comprises several process chambers 2a, 2b, 2c, ...2n, each allowing physico-chemical operations to be carried out on a substrate for the purpose of manufacturing semiconductor components, LEDs or flat screens.

[0038] The manufacturing equipment 1 includes, in particular, at least two loadlocks 100, 102, a transfer chamber 101, and at least two process chambers 2a, 2b, 2c, ...2n, such that the number of process chambers 2a, 2b, 2c, ...2n is between four and twelve. Figure 1 illustrates the specific case of semiconductor component manufacturing equipment 1 with six process chambers 2a-2f.

[0039] The at least two airlocks 100, 102 are each configured to receive a substrate and lower the atmospheric pressure surrounding the substrate to a predetermined transfer pressure and / or to receive a substrate at a predetermined transfer pressure and raise the pressure surrounding the substrate to atmospheric pressure.

[0040] For example, there is an inlet airlock 100 configured to receive a substrate in a chamber 104 of the airlock 100 and lower the atmospheric pressure surrounding the substrate in the chamber 104 to a predetermined transfer pressure, and an outlet airlock 102 configured to receive a substrate in a chamber 105 of the airlock 102 at the predetermined transfer pressure and raise the pressure surrounding the substrate to atmospheric pressure to remove the substrate from the chamber 105.

[0041] The transfer chamber 101 includes an enclosure 107 that can communicate with each of the process chambers 2a, 2b, 2c, ...2n and the airlocks 100, 102 via respective doors. The transfer chamber 101 further includes at least one robot 108 arranged in the enclosure 107, configured to transfer, at the predetermined transfer pressure, the substrates from chamber 104 of an airlock 100, 102 to a process chamber 2a, 2b, 2c, ...2n where the physicochemical operations can take place, and from a process chamber 2a, 2b, 2c, ...2n to chamber 105 of an airlock 100, 102 once these operations are completed.

[0042] Equipment 1 thus allows the airlocks 100, 102 to be shared for several process chambers 2a, 2b, 2c, ...2n.

[0043] As can be seen in [Fig.2], the equipment 1 (such as that illustrated in [Fig.1]) comprises as many turbomolecular vacuum pumps 3a, 3b, 3c, .. .3n as process chambers 2a, 2b, 2c, .. .2n.

[0044] The turbomolecular vacuum pumps 3a, 3b, 3c, .. .3n are fluidly connected to a respective process chamber 2a, 2b, 2c, .. .2n via respective first isolation valves 4a, 4b, 4c, .. .4n.

[0045] The first isolation valves 4a, 4b, 4c, ...4n are controllable in opening / closing. These are, for example, solenoid valves.

[0046] The turbomolecular vacuum pumps 3a, 3b, 3c, ...3n comprise a stator in which a rotor is configured to rotate at high speed in axial rotation, for example, a rotation at more than twenty thousand revolutions per minute. The pumped gases enter through a suction port and are discharged through a discharge port of the vacuum pump. turbomolecular 3a, 3b, 3c, ...3n. The rotor has at least one stage of blades and the stator has at least one stage of fins, the stages of blades and fins following one another axially along the axis of rotation of the rotor.

[0047] Equipment 1 further comprises at least one set of two primary process vacuum pumps 5a, 5b.

[0048] A primary vacuum pump is a positive displacement vacuum pump configured to draw in, transfer, and then discharge the gas to be pumped at atmospheric pressure or above, using two rotors. For example, a multistage primary vacuum pump may have between two and ten pumping stages. Each pumping stage consists of a pumping chamber containing two coupled rotors, each pumping chamber having an inlet and an outlet. Successive pumping stages are connected in series by interstage channels connecting the outlet of the preceding pumping stage to the inlet of the following stage. The primary vacuum pump is described as "dry" because, during operation, the rotors rotate inside the stator without any mechanical contact between themselves or with the stator, thus eliminating the need for oil in the pumping chamber(s).In another example, the primary vacuum pump is a screw pump.

[0049] Depending on the pumping applications, and in particular in manufacturing processes that may use corrosive process gases, such as semiconductor component manufacturing processes, the primary vacuum pumps of processes 5a, 5b can be further configured to be corrosion-resistant, especially against fluorine, chlorine, or bromine gases used in etching steps. For example, they can be nickel-plated.

[0050] The inlets of the two primary process vacuum pumps 5a, 5b of the assembly are fluidly connected in parallel via respective second isolation valves 6a, 6b to a common pipeline 7 fluidly connected in parallel to the outlets (discharge ports) of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n of the equipment 1 ([Fig.2]).

[0051] The second isolation valves 6a, 6b are controllable in opening / closing. These are, for example, solenoid valves.

[0052] Equipment 1 may include fourth isolation valves 12a, 12b, 12c, ... 12n at the discharge of the turbomolecular vacuum pumps 3a, 3b, 3c, ... 3n (upstream of the common pipeline 7). These fourth isolation valves 12a, 12b, 12c, ... 12n may be used in conjunction with the first isolation valves 4a, 4b, 4c, ... 4n to isolate the turbomolecular vacuum pumps 3a, 3b, 3c, ... 3n from themselves, for example during maintenance of a primary process vacuum pump 5a, 5b.

[0053] All outlets of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n are fluidly connected to the two primary process vacuum pumps 5a, 5b of at least one assembly (via the fourth isolation valves 12a, 12b, 12c, ...12n where applicable). For example, there is one assembly of two primary process vacuum pumps 5a, 5b fluidly connected to a maximum of two, three, four, five, or six turbomolecular vacuum pumps 3a, 3b, 3c, ...3n.

[0054] The two primary process vacuum pumps 5a, 5b of the assembly are for example identical or in other words, are the same two primary vacuum pumps 5a, 5b.

[0055] Each of the two primary process vacuum pumps 5a, 5b is configured to be able to lower the discharge pressure of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n to which they are fluidly connected, to a pressure below a pressure threshold below which a change in discharge pressure does not cause a change in suction pressure of the turbomolecular vacuum pump 3a, 3b, 3c, ...3n, including when a gas flow is injected at a predetermined maximum value into all the process chambers 2a, 2b, 2c, ...2n located upstream of said turbomolecular vacuum pumps 3a, 3b, 3c, ...3n.

[0056] A fortiori, each of the two primary process vacuum pumps 5a, 5b is configured to be able to ensure at the discharge of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n to which they are fluidly connected, a pressure lower than a manufacturer's maximum pressure beyond which the vacuum pump may be damaged, generally between 1.5 mbar (150 Pa) and 3 mbar (300 Pa).

[0057] This can be better understood with reference to the illustrative graph in [Fig.3] showing the suction pressure of a turbomolecular vacuum pump as a function of the discharge pressure for different values ​​of nitrogen flow to be pumped.

[0058] It is observed that for a nitrogen flow rate less than or equal to 2000 sccm, the suction pressure of the turbomolecular vacuum pump remains unchanged regardless of the discharge pressure for discharge pressures below the pressure threshold of 1 mbar (100 Pa). This pressure threshold ensures identical operation upstream of the turbomolecular vacuum pump.

[0059] Equipment 1 further includes a primary service vacuum pump 8 fluidly connected in parallel to the process chambers 2a, 2b, 2c, ...2n of equipment 1 via respective third isolation valves 9a, 9b, 9c, ...9n ( [Fig.2]).

[0060] The primary service vacuum pump 8 is a primary vacuum pump, as previously defined for process primary vacuum pumps 5a, 5b.

[0061] The third isolation valves 9a, 9b, 9c, ...9n are controllable in opening / closing. These are, for example, solenoid valves.

[0062] The primary service vacuum pump 8 makes it possible to ensure the vacuuming of at least one process chamber 2a, 2b, 2c, ...2n from atmospheric pressure, i.e. after a release to the air, for example for maintenance, the turbomolecular vacuum pump 3a, 3b, 3c, ...3n being isolated from the process chamber 2a, 2b, 2c, ...2n by the first isolation valves 4a, 4b, 4c, .. .4n. Indeed, the vacuuming of a process chamber 2a, 2b, 2c, ...2n from atmospheric pressure by at least one set of pairs of process vacuum pumps 5a, 5b by short-circuiting the turbomolecular vacuum pump 3a, 3b, 3c, ...3n, does not allow the discharge pressure of the turbomolecular vacuum pumps of equipment 1 to be kept below the pressure threshold which would not impact their pumping performance.

[0063] The equipment 1 also includes a control unit 11, such as a computer or an electronic board, comprising one or more controllers or microcontrollers or processors and a memory, for implementing the steps of a manufacturing process for components, in particular semiconductors, LEDs or flat screens.

[0064] The control unit 11 is specifically configured to control the gas flows injected into the process chambers, the opening and closing of the doors of the process chambers 2a, 2b, 2c, ...2n and of the airlocks 100, 102 allowing the input and output of substrates. This control unit 11 can also be configured to control the opening and closing of the first isolation valves 4a, 4b, 4c, ...4n, the second isolation valves 6a, 6b, the third isolation valves 9a, 9b, 9c, ...9n and the fourth isolation valves 12a, 12b, 12c, ...12n as appropriate.

[0065] The equipment 1 illustrated in [Fig. 1] thus comprises six process chambers 2a, 2b, 2c, ...2f, six turbomolecular vacuum pumps 3a, 3b, 3c, ...3f fluidly connected to a respective process chamber 2a, 2b, 2c, ...2f via six respective first isolation valves 4a, 4b, 4c, ...4f, a set of two primary process vacuum pumps 5a, 5b fluidly connected in parallel via respective second isolation valves 6a, 6b to a common pipeline 7 fluidly connected in parallel to the outlets of the six turbomolecular vacuum pumps 3a, 3b, 3c, ...3f of the equipment 1 and a primary service vacuum pump 8 fluidly connected in parallel to the process chambers 2a, 2b, 2c, ..2f of equipment 1 via six third isolation valves 9a, 9b, 9c, ..9f respectively.

[0066] The process chambers 2a, 2b, 2c, ...2n, the airlocks 100, 102, the transfer chamber 101, the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n, the first isolation valves 4a, 4b, 4c, ...4n and the third isolation valves 9a, 9b, 9c, ...9n mounted on the process chambers 2a, 2b, 2c, ...2n, are for example arranged in a cleanroom.

[0067] The primary process vacuum pumps 5a, 5b, the second isolation valves 6a, 6b and the primary service vacuum pump 8 can be arranged in a floor located below the cleanroom (called "basement" in English), the common piping 7 connecting the cleanroom floor to the basement floor.

[0068] The common pipeline 7 fluidly connecting the outlets (discharge ports) of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n to the second isolation valves 6a, 6b has, for example, a diameter of 160 mm.

[0069] The service pipe 10 fluidly connecting the pipes of the third isolation valves 9a, 9b, 9c, ...9n to the primary service vacuum pump 8 has, for example, a diameter of 40 mm or 50 mm.

[0070] The airlocks 100, 102 and the transfer chamber 101 have their own respective pumping devices.

[0071] During substrate manufacturing steps, under normal operating conditions, i.e., when the two primary process vacuum pumps 5a, 5b are functioning without failure, at least two primary process vacuum pumps 5a, 5b simultaneously draw air from the outlet of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n to which they are fluidly connected. The first isolation valves 4a, 4b, 4c, ...4n and the second isolation valves 6a, 6b are open, and the third isolation valves 9a, 9b, 9c, ...9n are closed.

[0072] In the event of a failure of one of the primary process vacuum pumps 5a, 5b, the second isolation valve 6a, 6b located upstream of the failed process vacuum pump 5a, 5b closes, isolating the failed process vacuum pump 5a, 5b. The other primary process vacuum pump 5a, 5b then provides the pumping service to the turbomolecular vacuum pumps 3a, 3b, 3c ... 3n.

[0073] After venting one or more process chambers, the primary service vacuum pump 8 establishes a vacuum from atmospheric pressure. The first isolation valves 4a, 4b, 4c, ...4n of the process chambers 2a, 2b, 2c, ...2n concerned are closed, the third isolation valves 9a, 9b, 9c, ...9n of the process chambers 2a, 2b, 2c, ...2n concerned are opened, the other third isolation valves 9a, 9b, 9c, ...9n remaining closed, so as to lower the pressure in the process chamber concerned without impacting the discharge pressure of the other turbomolecular vacuum pumps 3a, 3b, 3c, ...3n. Then, when the pressure is sufficiently low in the process chamber 2a, 2b, 2c, ...2n, the relevant third isolation valves 9a, 9b, 9c, ...9n are closed and the relevant first isolation valves 4a, 4b, 4c, ...4n are opened.

[0074] The primary service vacuum pump 8 does not need to operate continuously like the two primary process vacuum pumps 5a and 5b. The primary service vacuum pump 8 can be stopped or can operate at a reduced rotational speed. to limit its cost of use in electricity and fluids when not used for vacuum sealing.

[0075] The manufacturing equipment 1 is in particular configured to implement manufacturing steps for which the maximum value of the gas flow (nitrogen equivalent) injected into each process chamber 2a, 2b, 2c, .. .2n is less than 3,000 sccm (5.07 Pa.mVs), and for example of the order of 2,000 sccm (3.38 Pa.m3 / s) per process chamber 2a, 2b, 2c, .. .2n.

[0076] Each of the two primary process vacuum pumps 5a, 5b can be configured to be able to lower the discharge pressure of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n to which they are fluidly connected, to a pressure below a pressure threshold of 1 mbar (100 Pa) below which a variation in discharge pressure does not cause a variation in suction pressure of the turbomolecular vacuum pump 3a, 3b, 3c, ...3n, including when a gas flow of up to six times 2,000 sccm (3.38 Pa.m3 / s) is injected into all the process chambers 2a, 2b, 2c, ...2n located upstream of said turbomolecular vacuum pumps 3a, 3b, 3c, ...3n.

[0077] The manufacturing equipment 1 can be configured to perform etching steps or vacuum deposition of thin films such as a "physical vapor deposition" or PVD for the English "Physical Vapor Deposition".

[0078] Etching is a process that consists of removing one or more layers of material from the surface of a substrate. Etching is a critical step in the manufacturing of components, particularly microelectronics, as each substrate may undergo numerous etching steps. Etching can be physical or chemical and relies on bombarding the surface to be etched with ions, generally from a plasma.

[0079] Plasma sputtering is a form of physical deposition in the gas phase, more specifically vacuum sputtering, in which a metallic target cathode under vacuum is bombarded by ions from the plasma. Sputtering detaches atoms from the target, which are then deposited onto the substrate.

[0080] These cyclic manufacturing steps generally include a transfer step (also called an "idle" step) where a substrate enters the process chamber 2a, 2b, 2c, ..., 2n, followed by a process step proper where etching or deposition takes place. The cycle begins again with a new transfer step for the removal of the processed substrate and the entry of a new substrate to be processed. The transfer steps are carried out with a flow of neutral gas, generally nitrogen.

[0081] During the deposition, etching and transfer stages, the gas flows are relatively low, in particular on the order of 2,000 sccm (3.38 Pa.m3 / s) per chamber of processes, and therefore, these manufacturing processes are particularly suited to the invention.

[0082] Figure 4 shows a histogram of the discharge pressure of vacuum pumps turbomolecular that can be obtained during etching steps (called "active") and the discharge pressure of standby turbomolecular vacuum pumps, depending on the number of active turbomolecular vacuum pumps, of equipment 1 to six process chambers 2a, 2b, 2c, ...2f and a set of two associated primary process vacuum pumps 5a, 5b.

[0083] When two process chambers 2a, 2b, 2c, ..., 2n perform an etching step simultaneously with a respective gas flow rate of 2000 sccm (3.38 Pa.mVs), the discharge pressure of each active turbomolecular vacuum pump is 0.47 mbar (47 Pa) and the discharge pressure of the four turbomolecular vacuum pumps in the standby process chambers is 0.26 mbar (26 Pa). In the event of a failure of one of the primary process vacuum pumps 5a, 5b, the discharge pressure of each active turbomolecular vacuum pump is 0.49 mbar (49 Pa) and the discharge pressure of the four turbomolecular vacuum pumps in the standby process chambers is 0.28 mbar (28 Pa).

[0084] When four process chambers 2a, 2b, 2c, ..., 2n perform an etching step simultaneously with a respective gas flow rate of 2000 sccm (3.38 Pa.mVs), the discharge pressure of each active turbomolecular vacuum pump is 0.55 mbar (55 Pa) and the discharge pressure of the two turbomolecular vacuum pumps in the standby process chambers is 0.34 mbar (34 Pa). In the event of a failure of one of the primary process vacuum pumps 5a, 5b, the discharge pressure of each active turbomolecular vacuum pump is 0.6 mbar (60 Pa) and the discharge pressure of the four turbomolecular vacuum pumps in the standby process chambers is 0.4 mbar (40 Pa).

[0085] When six process chambers 2a, 2b, 2c, ..., 2n perform an etching step simultaneously with a respective pumped gas flow of 2000 sccm (3.38 Pa.m³ / s), the discharge pressure of each active turbomolecular vacuum pump is 0.62 mbar (62 Pa). In the event of a failure of one of the primary process vacuum pumps 5a, 5b, the discharge pressure of each active turbomolecular vacuum pump is 0.7 mbar (70 Pa).

[0086] It is observed that the discharge pressure of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3f increases with the increasing number of active turbomolecular vacuum pumps, while remaining below the threshold pressure of 1 mbar (100 Pa) even for six process chambers 2a, 2b, 2c, ...2n operating simultaneously. Therefore, there are no upstream impacts in the process chambers 2a, 2b, 2c, ...2n due to the reduction in the number of process vacuum pumps compared to the prior art. It is also observed that in the event of a failure of one of the two primary process vacuum pumps 5a, 5b, the discharge pressure of the active and standby turbomolecular vacuum pumps increases slightly but not significantly.

[0087] This sharing of the primary process vacuum pumps 5a, 5b is possible, firstly, because, for pressures below a pressure threshold, a variation in discharge pressure does not cause a variation in the suction pressure of the turbomolecular vacuum pump 3a, 3b, 3c, ...3n. In other words, as long as the discharge pressure of the turbomolecular vacuum pump 3g, 3h, 3i, ...3n is below the pressure threshold, there is no impact upstream of the turbomolecular vacuum pump 3a, 3b, 3c, ...3n. The same pumping performance is expected for the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n as if they had a dedicated primary pump.

[0088] The two primary process vacuum pumps 5a, 5b operating simultaneously, each configured to maintain the discharge pressures of the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n below the pressure threshold, also ensures that the vacuum is maintained in the process chambers 2a, 2b, 2c, ...2n during manufacturing steps in the event of a failure of one of the process vacuum pumps 5a, 5b, at least long enough to complete the ongoing manufacturing steps. This prevents damage to the substrates being manufactured in the process chambers 2a, 2b, 2c, ...2n.

[0089] Manufacturing equipment 1 is thus less expensive to install and reduces the footprint (saving 40% to 50%) because it includes fewer primary vacuum pumps and reduces the number of pipes connecting the turbomolecular vacuum pumps 3a, 3b, 3c, ...3n from the cleanroom to the basement, as well as the number of electrical (boxes and electrical cables) and fluid connections required for the operation of the primary vacuum pumps. It is also less expensive to operate due to reduced electricity consumption (saving 30% to 60%), reduced purge gas consumption (saving at least 50%), and reduced cooling heat transfer fluid consumption (saving 50%) required for the operation of each primary vacuum pump.Equipment 1 is also more reliable than prior art equipment because it has a backup primary vacuum pump in case of failure of a primary vacuum pump of processes 5a, 5b and therefore avoids the loss of a substrate in production.

[0090] Figure 5 shows another example of an embodiment.

[0091] In this example, the equipment 1 comprises eight process chambers 2a, 2b, 2c, ...2h, eight fluidically connected turbomolecular vacuum pumps 3a, 3b, 3c, ..3h to a process chamber 2a, 2b, 2c, ..2h respective via eight first isolation valves 4a, 4b, 4c, ..4h respective and two sets of two primary process vacuum pumps 5a, 5b.

[0092] Two primary process vacuum pumps 5a, 5b of a first set are fluidly connected in parallel via second isolation valves 6a, 6b respectively to a common pipeline 7 fluidly connected in parallel to the outlets of four first turbomolecular vacuum pumps 3a, 3b, 3c, ...3f of equipment 1.

[0093] Two primary process vacuum pumps 5a, 5b of a second set are fluidly connected in parallel via respective second isolation valves 6a, 6b to a common pipeline 7 fluidly connected in parallel to the outlets of four second turbomolecular vacuum pumps 3g, 3h, 3i, ...31 of equipment 1.

[0094] A primary service vacuum pump 8 is fluidly connected in parallel to the eight process chambers 2a, 2b, 2c, .. .21 of the equipment 1 via eight respective third isolation valves 9a, 9b, 9c, ...91.

[0095] The transfer chamber 101 can include several robots 108 in the enclosure 107 to facilitate the distribution of substrates in the eight process chambers 2a, 2b, 2c, 2h.

Claims

Demands

1. Manufacturing equipment (1), in particular for semiconductor components, LEDs or flat panel displays, comprising at least two process chambers (2a, 2b, 2c, ...2n) and as many turbomolecular vacuum pumps (3a, 3b, 3c, ...3n) fluidly connected to a respective process chamber (2a, 2b, 2c, ...2n) via respective first isolation valves (4a, 4b, 4c, ...4n), characterized in that it further comprises: - at least one set of two primary process vacuum pumps (5a, 5b), the inlets of said primary process vacuum pumps (5a, 5b) of the set being fluidly connected in parallel via respective second isolation valves (6a, 6b) to a common pipeline (7) fluidly connected in parallel to the outlets of the turbomolecular vacuum pumps (3a, 3b, 3c, ...3n), all the outputs of the turbomolecular vacuum pumps (3a, 3b, 3c, ...3n) being fluidly connected to the two primary process vacuum pumps (5a, 5b) of at least one assembly, and - a primary service vacuum pump (8) fluidly connected in parallel to the process chambers (2a, 2b, 2c, ...2n) of said equipment (1) via respective third isolation valves (9a, 9b, 9c, ...9n).

2. Equipment (1) according to the preceding claim, characterized in that the primary process vacuum pumps (5a, 5b) of the assembly are identical.

3. Equipment (1) according to any one of the preceding claims characterized in that each of the two primary process vacuum pumps (5a, 5b) is configured to be able to lower the discharge pressure of the turbomolecular vacuum pumps (3a, 3b, 3c, ...3n) to which they are fluidly connected, to a pressure below a pressure threshold below which a change in discharge pressure does not cause a change in suction pressure of the turbomolecular vacuum pump (3a, 3b, 3c, ...3n), including when a gas flow is injected at a predetermined maximum value into all the process chambers (2a, 2b, 2c, ... 2n) located upstream of said turbomolecular vacuum pumps (3a, 3b, 3c, ...3n).

4. Equipment (1) according to any one of the preceding claims characterized in that a set of two primary process vacuum pumps (5a, 5b) is fluidly connected to two, three, four, five or six turbomolecular vacuum pumps (3a, 3b, 3c, ...3n).

5. Equipment (1) according to any one of the preceding claims characterized in that the process chambers (2a, 2b, 2c, ...2n), the turbomolecular vacuum pumps (3a, 3b, 3c, ...3n), the first isolation valves (4a, 4b, 4c, ..4n) and the third isolation valves (9a, 9b, 9c, ...9n) are arranged in a cleanroom and the primary process vacuum pumps (5a, 5b), the second isolation valves (6a, 6b) and the primary service vacuum pump (8) are arranged in a floor located below the cleanroom.

6. Equipment (1) according to any one of the preceding claims characterized in that a service pipe (10) fluidly connecting the pipes of the third isolation valves (9a, 9b, 9c, ...9n) to the primary service vacuum pump (8) has a diameter of 40 mm or 50 mm and the common pipe (7) has a diameter of 160 mm.

7. Equipment (1) according to any one of the preceding claims, characterized in that it comprises: - at least two airlocks (100, 102), each configured to receive a substrate in a chamber (104, 105) of the airlock (100, 102) and lower the atmospheric pressure in the chamber (104, 105) to a predetermined transfer pressure and / or to receive a substrate at a predetermined transfer pressure in a chamber (104, 105) of the airlock (100, 102) and raise the pressure in the chamber (104, 105) to atmospheric pressure, - a transfer chamber (101) configured to transfer the substrates at the predetermined transfer pressure from the airlock (100, 102) to a process chamber (2a, 2b, 2c, ...2n) and from a process chamber (2a, 2b, 2c, ...2n) towards a lock (100, 102).

8. Equipment (1) according to any one of the preceding claims characterized in that it comprises a control unit (11) configured to control the opening and closing of the first isolation valves (4a, 4b, 4c, ...4n), the second isolation valves (6a, 6b) and the third isolation valves (9a, 9b, 9c, ...9n).

9. Equipment (1) according to any one of the preceding claims characterized in that it is configured to implement steps manufacturing for which a maximum value of the gas flow injected into each process chamber (2a, 2b, 2c, ...2n) is less than 3,000 sccm (5.07 Pa.mVs).

10. Equipment (1) according to any one of the preceding claims, characterized in that it is configured to carry out etching or vacuum deposition steps of thin films.

11. A manufacturing method characterized in that it is implemented in manufacturing equipment (1) according to any one of the preceding claims, wherein during the substrate manufacturing steps: - in a non-failure situation, the second isolation valves (6a, 6b) are open such that the at least two primary process vacuum pumps (5a, 5b) simultaneously draw from the outlet of the turbomolecular vacuum pumps (3a, 3b, 3c, ...3n) to which they are fluidly connected, - in the event of a failure of one of the primary process vacuum pumps (5a, 5b), the second isolation valve (6a, 6b) located upstream of the failed process vacuum pump (5a, 5b) closes, isolating the failed process vacuum pump (5a, 5b), the other primary process vacuum pump (5a, 5b) alone ensuring the pumping at the discharge of the pumps turbomolecular vacuum (3a, 3b, 3c ...3n).

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