1. A device for thermally stabilizing an object (20) to be cooled at a predetermined temperature by circulating a fluid, characterized in that it includes:
a pressure controlled Dewar flask (10) for providing a gas;
a means (11, 26) for pre-cooling the gas;
a cryostat (16) in which the object to be cooled is placed;
a siphon (13) for transferring the gas from the Dewar flask to the cryostat; the siphon including within at least one sieve (14) providing thermal filtration of the gas, and
a variable flow outlet port (17) providing discharge of the gas.
2. The device according to claim 1, characterized in that the sieve is comprised of lead or rare earth beads.
3. The device according to claim 2, characterized in that the beads have a diameter from about 200 to 500 m.
4. The device according to any of claims 1 to 3, characterized in that it includes at least two sieves (14, 15), at least one sieve being placed within the siphon at the outlet of the exchanger and another one being placed within the siphon upstream from the object to be cooled.
5. The device according to any of claims 1 to 4, characterized in that the gas is helium for cooling to a temperature between 5 and 30 K.
6. The device according to any of claims 1 to 5, characterized in that the siphon includes a thin wall of stainless steel.
7. The device according to any of claims 1 to 5, characterized in that the siphon is coaxial.
8. The device according to any of claims 1 to 7, characterized in that an adjustable power electrical resistor is adjacent to the object (20).
9. The device according to any of claims 1 to 8, characterized in that a spiral (26) or a coil forms the siphon at the bottom of the Dewar flask (10).
10. The device according to any of claims 1 to 9, characterized in that the means for pre-cooling the gas comprises a coaxial exchanger (11).
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 semiconductor device comprising:
a plurality of inter-level dielectric films which are stacked and provided in plural layers above a substrate;
at least one first conductor which is provided in at least one inter-level dielectric film of the stacked inter-level dielectric films; and
a plurality of second conductors which are provided in the inter-level dielectric film in which the first conductor is provided and which are connected to the lower surface of the first conductor and which are extended along the downward direction from the first conductor and further extended along a first direction and a second direction perpendicular to the first direction in such a manner as to be spaced apart from each other to form a lattice shape.
2. The semiconductor device according to claim 1, further comprising:
at least one lower layer conductor which is electrically unconnected to the first conductor and the second conductors and which is provided at the position overlapped at least partly with the first conductor in an inter-level dielectric film below the inter-level dielectric film in which the first conductor and the second conductors are provided,
the second conductors being formed passing through the inter-level dielectric film in which the first conductor is provided along the film thickness direction thereof at the position off the position above the lower layer conductor.
3. The semiconductor device according to claim 1, wherein
the second conductors are extended along the longitudinal direction of the first conductor and along the width direction perpendicular to the longitudinal direction in such a manner as to be spaced apart from each other to form a lattice shape.
4. The semiconductor device according to claim 1, wherein
a pitch between the adjacently provided second conductors is not more than double the width of each of the second conductors.
5. The semiconductor device according to claim 1, wherein
the width of the first conductor is 1 \u03bcm or more.
6. The semiconductor device according to claim 1, wherein
the width of each of the second conductors is not more than half that of the first conductor.
7. The semiconductor device according to claim 1, wherein
the width of each of the second conductors is 0.5 \u03bcm or less.
8. The semiconductor device according to claim 1, wherein
the second conductors are provided such that the coverage of the lower surface of the first conductor by the second conductors becomes 10% or more.
9. The semiconductor device according to claim 1, wherein
each of the inter-level dielectric films is a low-k inter-level dielectric film having a relative dielectric constant of 3.4 or less.
10. The semiconductor device according to claim 2, further comprising:
at least one another dielectric film which has a Young’s modulus of 30 GPa or more and which is provided between the inter-level dielectric film in which the first conductor and second conductors are provided and the inter-level dielectric film in which the lower layer conductor is provided,
the second conductors being provided with reaching the another dielectric film at least partly.
11. The semiconductor device according to claim 2, wherein
the lower layer conductor is a part of a conductive passage, and
the second conductors are dummy wirings to which a current is not actually supplied.
12. A semiconductor device comprising:
a plurality of inter-level dielectric films which are stacked and provided in plural layers above a substrate;
at least one lower layer conductor which is provided as a part of a conductive passage in at least one inter-level dielectric film of the stacked inter-level dielectric films; and
at least one first conductor which is provided at the position above and substantially overlapping the lower layer conductor and the inter-level dielectric film in which the lower layer conductor is provided in such a manner as to pass through an inter-level dielectric film above the inter-level dielectric film in which the lower layer conductor is provided along the film thickness direction thereof and which is electrically connected to the lower layer conductor to serve as a part of the conductive passage.
13. The semiconductor device according to claim 12, wherein
each of the inter-level dielectric films is a low-k inter-level dielectric film having a relative dielectric constant of 3.4 or less.
14. The semiconductor device according to claim 12, further comprising:
at least one another dielectric film which has a Young’s modulus of 30 GPa or more and which is provided between the inter-level dielectric film in which the lower layer conductor is provided and the inter-level dielectric film in which the first conductor is provided,
the first conductor being provided with reaching the another dielectric film at least partly.
15. A semiconductor device comprising:
a plurality of inter-level dielectric films which are stacked and provided in plural layers above a substrate;
at least one lower layer conductor which is provided in at least one inter-level dielectric film of the stacked inter-level dielectric films; and
at least one first conductor which is electrically unconnected to the lower layer conductor and which is provided in an inter-level dielectric film above the inter-level dielectric film in which the lower layer conductor is provided at the position above the lower layer conductor and overlapping the lower layer conductor partly, at least a part of the first conductor having a smaller line width at the position off the area above the lower layer conductor and, at this position, passing through the inter-level dielectric film above the inter-level dielectric film in which the lower layer conductor is provided along the film thickness direction thereof.
16. The semiconductor device according to claim 15, wherein
each of the inter-level dielectric films is a low-k inter-level dielectric film having a relative dielectric constant of 3.4 or less.
17. The semiconductor device according to claim 15, further comprising:
at least one another dielectric film which has a Young’s modulus of 30 GPa or more and which is provided between the inter-level dielectric film in which the lower layer conductor is provided and the inter-level dielectric film in which the first conductor is provided,
the first conductor being provided with reaching the another dielectric film at least partly.
18. A semiconductor device comprising:
a plurality of inter-level dielectric films which are stacked and provided in plural layers above a substrate;
at least one lower layer conductor which is provided in at least one inter-level dielectric film of the stacked inter-level dielectric films; and
at least one first conductor which is electrically unconnected to the lower layer conductor and which has first and second current application portions provided in such a manner as to pass through an inter-level dielectric film above the inter-level dielectric film in which the lower layer conductor is provided along the film thickness direction thereof and sandwich the position above and overlapping the lower layer conductor, the first and second current application portions being electrically connected to each other to serve as a part of a conductive passage; and
at least one upper layer conductor which is provided in such a manner as to pass through an inter-level dielectric film above the inter-level dielectric film in which the first and second current application portions of the first conductor are provided along the film thickness direction thereof at the position above and overlapping the lower layer conductor and which is electrically connected to the first and second current application portions of the first conductor to serve as a part of the conductive passage.
19. The semiconductor device according to claim 18, wherein
each of the inter-level dielectric films is a low-k inter-level dielectric film having a relative dielectric constant of 3.4 or less.
20. The semiconductor device according to claim 18, further comprising:
at least two another dielectric films which have a Young’s modulus of 30 GPa or more and which is provided between the inter-level dielectric film in which the lower layer conductor is provided and the inter-level dielectric film in which the first conductor is provided and between the inter-level dielectric film in which the first conductor is provided and the inter-level dielectric film in which the upper layer conductor is provided,
each of the first conductor and upper layer conductor being provided with reaching the another dielectric film below the inter-level dielectric film in which each conductor is provided respectively at least partly.