1. A method of encapsulating a microelectronic device arranged on a substrate, comprising at least the following steps:
a) formation of a portion of sacrificial material covering at least one part of the microelectronic device, the volume of which occupies a space intended to form at least one part of a cavity in which the device is intended to be encapsulated,
b) deposition of a layer based on at least one getter material, covering at least one part of the portion of sacrificial material,
c) formation of at least one orifice through at least the layer of getter material, forming an access to the portion of sacrificial material,
d) elimination of the portion of sacrificial material via the orifice, forming the cavity in which the microelectronic device is encapsulated,
e) sealing of the cavity.
2. The method according to claim 1, wherein step a) of formation of the portion of sacrificial material comprises at least the implementation of the following steps:
a1) deposition of a layer based on sacrificial material on the substrate and covering at least the microelectronic device,
a2) formatting of a part of the sacrificial layer, a remaining portion of the sacrificial layer forming said portion of sacrificial material.
3. The method according to claim 1, further comprising, between step a) of formation of the portion of sacrificial material and step b) of deposition of the layer of getter material, a step of thermal flow of the portion of sacrificial material.
4. The method according to claim 1, further comprising, between step a) of formation of the portion of sacrificial material and step b) of deposition of the layer of getter material, a step of deposition of a protective layer on the portion of sacrificial material, the layer of getter material being deposited, during step b), on the protective layer, the orifice being moreover formed, during step c), through the protective layer.
5. The method according to claim 4, wherein the protective layer has a thickness between around 10 nm and 1 \u03bcm andor is based on chromium andor copper.
6. The method according to claim 1, further comprising, between step b) of deposition of the layer of getter material and step c) of formation of the orifice, a step of deposition of a hermeticity layer on the layer of getter material, the orifice being moreover formed, during step c), through the hermeticity layer.
7. The method according to claim 6, further comprising, between step b) of deposition of the layer of getter material and the step of deposition of the hermeticity layer, a step of etching a part of the layer of getter material, a remaining portion of the layer of getter material partially covering the portion of sacrificial material.
8. The method according to claim 6, wherein the hermeticity layer has a thickness between around 500 nm and 10 \u03bcm, andor is based on titanium andor chromium andor copper andor at least one metal andor based on a material transparent to a range of operating wavelengths of the microelectronic device.
9. The method according to claim 1, further comprising, between step b) of deposition of the layer of getter material and step c) of formation of the orifice, a step of etching a part of the layer or layers formed on the portion of sacrificial material, the remaining portions of said deposited layer(s) forming a cover or a part of a cover covering the portion of sacrificial material.
10. The method according to claim 1, wherein step e) of sealing comprises the deposition of a layer of a material andor the formation of at least one plug, obstructing the orifice on the getter material or on the hermeticity layer.
11. The method according to claim 10, wherein the material andor the plug obstructing the orifice are based on a metal andor an oxide andor a getter material.
12. The method according to claim 1, further comprising, during step a) of formation of the portion of sacrificial material, the formation of at least one second orifice in the portion of sacrificial material, the layers deposited during subsequent steps also being deposited in said second orifice, forming at least one micro-pillar in the cavity.
13. The method according to claim 1, wherein the portion of sacrificial material has a thickness between around 1 \u03bcm and 20 \u03bcm, andor the sacrificial material being based on photosensitive resin or at least one metal.
14. The method according to claim 1, wherein the layer of getter material has a thickness between around 200 nm and 5 \u03bcm, andor the getter material being based on titanium andor zirconium andor vanadium.
15. The method according to claim 1, further comprising, after step e) of sealing of the cavity, a step of thermal activation of the getter material.
16. The method according to claim 1, further comprising, between step c) of formation of the orifice and step d) of elimination, or between step d) of elimination and step e) of sealing, the following steps:
formation of a second portion of sacrificial material on the layer of getter material or on the hermeticity layer, the volume of which occupies a space intended to form at least one part of a second cavity,
deposition of a second layer based on at least one getter material andor a hermeticity layer covering at least one part of the second portion of sacrificial material,
formation of at least one second orifice through at least the second layer of getter material andor the hermeticity layer, forming an access to the second portion of sacrificial material;
and further comprising, between the step of formation of the second orifice and step d) of elimination, or during step d) of elimination, or between step d) of elimination and step e) of sealing, a step of elimination of at least the second portion of sacrificial material via the second orifice, forming the second cavity.
17. The method according to claim 16, further comprising, between the step of deposition of the second layer of getter material andor the hermeticity layer and the step of formation of the second orifice, a step of etching a part of the layer or layers formed on the second portion of sacrificial material, the remaining portions of said deposited layer(s) forming a cover or a part of a cover covering the second portion of sacrificial material.
18. The method according to claim 16, wherein step e) of sealing comprises the deposition of a layer of a material andor the formation of at least one plug, obstructing the second orifice on the second layer of getter material andor on the hermeticity layer.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A control method for an internal combustion engine, which internal combustion engine (M) comprises at least one component (2; 31) moving between two end positions, each moving component (2; 31) transmitting vibrations at the location of at least one of its end positions during the operation of the internal combustion engine (M), the method providing for the acquisition of a signal (Sv; Sc; S) correlated with these vibrations.
2. The method of claim 1, characterized in that the signal (Sv; Sc; S) is correlated with the impact energy determined by the impact of the component against an abutment (2A; 32, 33) disposed in at least one of these end positions.
3. The method of claim 2, characterized in that the speed of impact (Viv; Vic) correlated with the impact is calculated as a function of this signal (Sv; Sc; S).
4. The method of claim 2, characterized in that the instant (tc; tP1, tP2) in which the impact takes place is acquired.
5. The method of claim 1, characterized in that the internal combustion engine (M) comprises a plurality of components (2, 31) moving between two end positions, each moving component (2, 31) transmitting vibrations at the location of at least one of these end positions during the operation of the internal combustion engine (M), the method providing for the acquisition of a signal (Sv; Sc; S) correlated with these vibrations.
6. The method of claim 5, characterized in that these signals (Sv; Sc; S) correlated with the vibrations of the moving components (2, 31) are acquired by means of at least one sensor (42, 43; 44).
7. The method of claim 6, characterized in that the signals (Sv; Sc; S) are filtered in order to isolate the vibrations transmitted by an individual moving component (2; 31).
8. The method of claim 6, characterized in that the sensor (42; 43, 44) is an accelerometer.
9. The method of claim 7, characterized in that the internal combustion engine (M) comprises a detonation sensor (44), the method providing for the use of this sensor (44) to acquire the signal (S).
10. The method of claim 2, characterized in that the moving component is a valve (2) of the internal combustion engine (M) and the abutment is the seat (2A) of the valve (2).
11. The method of claim 10, characterized in that the moving component is a slide (31) of a hydraulic slide distributor valve (16) controlling the valve (2), the slide (31) being adapted to assume two stable positions against two opposing abutments (32, 33).
12. The method of claim 11, characterized in that the positions of the slide (31) are interpolated between the end positions as a function of the signal (Sc).
13. A control device for an internal combustion engine, which internal combustion engine (M) comprises at least one component (2; 31) moving between two end positions, each moving component (2; 31) transmitting vibrations at the location of at least one of its end positions during the operation of the internal combustion engine (M), the device comprising acquisition means (40, 43; 40, 42; 40; 44) for acquiring a signal (Sv; Sc; S) correlated with these vibrations.
14. The device of claim 13, characterized in that the moving component (2; 31) is adapted to impact against at least one abutment (2A; 32, 33) disposed in one of the end positions.
15. The device of claim 14, characterized in that it comprises calculator means (40) for calculating the speed of impact (Viv; Vic) correlated with the impact as a function of the signal (Sv; Sc; S).
16. The device of claim 14, characterized in that it comprises acquisition means (40, 42; 40, 43; 40; 44) for acquiring the instant (tc; tP1; tP2) in which the impact takes place.
17. The device of claim 12, characterized in that the internal combustion engine (M) comprises a plurality of components (2; 31) moving between two end positions, each moving component (2; 31) transmitting vibrations at the location of at least one of its end positions during the operation of the engine (M), the device comprising acquisition means (40, 43; 40, 42; 40; 44) for acquiring a signal (Sv; Sc; S) correlated with these vibrations.
18. The device of claim 17, characterized in that the acquisition means (40, 42; 40, 43; 40; 44) comprise at least one sensor (43, 42; 44).
19. The device of claim 17, characterized in that the acquisition means (40, 42; 40, 43; 40; 44) comprise filters (F1, F2, F3 to FN) adapted to filter the signal (Sv; Sc; S).
20. The device of claim 18, characterized in that the sensor (42, 43; 44) is an accelerometer.
21. The device of claim 19, characterized in that the internal combustion engine (M) comprises a detonation sensor (44), the method providing for the use of this sensor (44) as an accelerometer in order to acquire the signal (S).
22. The device of claim 13, characterized in that the moving component (2; 31) is a valve (2) of the internal combustion engine (M) and the abutment is the seat (2A) of the valve (2).
23. The device of claim 22, characterized in that the moving component is a slide (31) of a hydraulic slide distributor valve (16) controlling the valves (2), the slide (31) being adapted to assume two stable positions against two opposing abutments (32, 33).