Source: http://www.google.com/patents/US6323426?ie=ISO-8859-1&dq=5998925
Timestamp: 2014-10-23 02:32:29
Document Index: 72209614

Matched Legal Cases: ['arts 15', 'arts 15', 'arts 15', 'arts 15', 'arts 15', 'arts 15', 'arts 15', 'arts 15']

Patent US6323426 - Mounting structure for semiconductor device - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA mounting structure for a high temperature superconductor device, such as a filter, housed in a closed vacuum chamber and operated at a low temperature. The filter has dielectric substrate having: first and second surfaces; a circuit portion made of a superconducting thin film formed on the first surface...http://www.google.com/patents/US6323426?utm_source=gb-gplus-sharePatent US6323426 - Mounting structure for semiconductor deviceAdvanced Patent SearchPublication numberUS6323426 B1Publication typeGrantApplication numberUS 09/222,313Publication dateNov 27, 2001Filing dateDec 29, 1998Priority dateJan 14, 1998Fee statusLapsedPublication number09222313, 222313, US 6323426 B1, US 6323426B1, US-B1-6323426, US6323426 B1, US6323426B1InventorsHiroki Hoshizaki, Masashi FuseOriginal AssigneeAdvanced Mobile Telecommunication Technology Inc.Export CitationBiBTeX, EndNote, RefManPatent Citations (3), Referenced by (7), Classifications (16), Legal Events (5) External Links: USPTO, USPTO Assignment, EspacenetMounting structure for semiconductor deviceUS 6323426 B1Abstract A mounting structure for a high temperature superconductor device, such as a filter, housed in a closed vacuum chamber and operated at a low temperature. The filter has dielectric substrate having: first and second surfaces; a circuit portion made of a superconducting thin film formed on the first surface of the dielectric substrate; and a ground layer consisting of a superconducting thin film formed on second surface of the dielectric substrate and a metal film deposited on the superconducting thin film. The mounting structure comprises: a device holder for holding the filter thereon; a conductive layer intervening between the ground layer of the filter and the device holder; urging parts for resiliently urging the filter toward the device holder. The conductive layer is made of a metal selected from among the group consisting of gold, silver, copper, aluminum and an alloy made of at least one of gold, silver, copper, and aluminum.
What is claimed is: 1. A mounting structure for a superconductor device housed in a closed vacuum chamber, said superconductor device adapted to have a signal inputted from a first external device and to output a signal to a second external device and comprising: a dielectric substrate having first and second surfaces; a circuit layer made of a superconducting thin film and deposited on said first surface of said dielectric substrate to allow said inputted signal to pass therethrough; and a ground layer made of a conductive material and deposited on said second surface of said dielectric substrate,
said mounting structure comprising: a device holder having a base surface and adapted to hold said superconductor device thereon; a conductive layer intervening between said ground layer of said superconductor device and said device holder, and having a first surface facing said ground layer of said superconductor device and a second surface facing said base surface of said device holder, said base surface of said device holder and said ground layer of said superconductor device electrically connected with each other through said conductive layer; an input connector electrically connected to said superconductor device and said first external device to allow said signal to be inputted from said first external device to said superconductor device; an output connector electrically connected to said superconductor device and said second external device to allow said signal to be outputted from said superconductor device to said second external device; and fastening means for resiliently fastening said superconductor device to said device holder to have said first surface of said conductive layer held in press contact with said ground layer of said superconductor device and to have said second surface of said conductive layer held in press contact with said base surface of said device holder to ensure that said ground layer of said superconductor device is electrically connect to said device holder through said conductive layer, wherein said fastening means comprising a plurality of plate springs each positioned at each of said contact areas of said conductive layer to have said first surface of said conductive layer held in press contact with said ground layer of said superconductor device and to have said second surface of said conductive layer held in press contact with said base surface of said device holder to ensure that said ground layer of said superconductor device is electrically connected to said device holder through each of said contact areas of said conductive layer. 2. The mounting structure as set forth in claim 1, in which said conductive layer has a plurality of contact areas each partially covering an area of said dielectric substrate.
11. The mounting structure as set forth in claim 1, in which said conductive layer is made of a material having a specific resistance ρ less than 3 μΩ�cm.
12. The mounting structure as set forth in claim 1, in which said conductive layer is made of a material having a modulus of elasticity more than 5�106 psi and less than 20�106 psi.
There have so far been proposed a wide variety of superconductor devices, especially high temperature superconductor (hereinlater referred to simply as �HTS�) devices, preferably utilized for an integrated circuit, a filter, an amplifier and so forth. This type of superconductor device generally comprises a dielectric substrate and superconducting thin film layers deposited on both of surfaces of the dielectric substrate by a physical vapor deposition method, e.g., a sputtering method or a reactive vapor deposition method. Each of the superconducting thin film layers is made of a ceramics system, such as an yttrium, barium, and copper oxide system (hereinlater referred to simply as a �YBaCuO system�) of the HTS.
Typical superconductor device is however required to be housed in a closed vacuum chamber at a low pressure of 2�10−2 Pa or less and cooled at a low temperature of 80 K in order to cause the aforesaid superconductive phenomena. The superconductor device should therefore be contained in a device holding apparatus 1 as shown in FIG. 13 to keep the above pressure and temperature.
Referring to FIG. 16 of the drawings, there is shown a graph showing a filter function in a frequency response of a typical filter including the above filter 91. As shown in FIG. 16, the typical filter has a large response within a passband. The frequency response of the filter is attenuated outside of the passband, more specifically in a frequency region outside of a region between fL and fH as shown in FIG. 16. The typical filter has a filter function in frequency response generally defined as attenuation �A� outside of the passband of 90 dB or more. Likewise, the HTS device may preferably have a filter function in frequency response defined as the attenuation A outside of the passband of 90 dB or more.
In the conventional mounting structure 90, the adhesive layer 97 can be made of an indium, which is inexpensive. The indium has a specific resistance ρ of 8.8 μΩ�cm and a modulus of elasticity of 1.57�106 psi.
The above adhesive layer 97 is, however, liable to seal a gas in a boundary between the first surface 97 b of the adhesive layer 97 and the ground layer of the filter 91 and a boundary between the second surface 97 b of the adhesive layer 97 and the base surface 94 a of the device holder 94, owing to the extremely low modulus of elasticity of the indium. The sealed gas in the aforesaid boundaries is gradually released, thereby making it impossible to keep the specific low pressure of 2�10−2 Pa in the closed vacuum chamber and the specific low temperature of 80 K.
In order to solve the above problem in the conventional mounting structure 90, the closed vacuum chamber is conventionally being pumped down to a low pressure of lower than 2�10−2 Pa by a vacuum pump (not shown) while the device 4 is being operated in the closed vacuum chamber. Therefore, the gas can be pumped out even when the gas sealed in the boundaries is released while the device is operated in the closed vacuum chamber.
In order to keep a low pressure of 2�10−2 Pa, the amount of the gas released from the boundaries should be limited to 1�10−9 Pa�m3/sec or less, which is the same amount of the gas released from a chamber wall of the housing 2. The gas sealed in the boundaries is, however, apt to be gradually released to have the amount of the released gas exceed this limitation of 1�10−9 Pa�m3/sec, thereby making it impossible to keep the specific low pressure of 2�10−2 Pa while the device is being operated in the conventional mounting structure 90. This causes a problem for the operation of the superconductor device.
Furthermore, the superconductor device such as a filter is required to have a high conductivity because the ground layer of the superconductor device has an extremely low contact resistance against the base surface 94 a of the device holder 94. The conventional mounting structure 90 however cannot establish a high conductivity because the adhesive layer 97 is made of the indium which has a low conductivity, i.e., the specific resistance ρ of 8.8 μΩ�cm.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a mounting structure for a superconductor device, more particularly, for a high temperature superconductor device, which is used under a specific condition such as at a low temperature of 80 K or less and a low pressure of 2�10−2 Pa or less in a closed vacuum chamber.
In the mounting structure, the superconducting thin film layer may be made of a high temperature superconducting material. The conductive layer may be made of a metal selected from among the group consisting of gold, silver, copper, aluminum and an alloy made of at least one of gold, silver, copper and aluminum. The conductive layer may be made of a material having a specific resistance ρ less than 3 μΩ�cm. The conductive layer may be made of a material having a modulus of elasticity more than 5�106 psi and less than 20�106 psi.
FIG. 2 is a fragmental cross sectional view taken substantially on line F2�F2 of FIG. 1;
FIG. 4 is a cross sectional view taken substantially on line F4�F4 of FIG. 3;
FIG. 8 is a fragmental cross sectional view taken substantially on line F8�F8 of FIG. 7;
FIG. 9 is a fragmental cross sectional view taken substantially on line F9�F9 of FIG. 7;
FIG. 11 is a fragmental cross sectional view taken substantially on line F11�F11 of FIG. 10;
FIG. 15 is a fragmental cross sectional view taken substantially on line F15�F15 of FIG. 14; and
Referring now to FIGS. 1 to 4 of the drawings, there is shown a first preferred embodiment of a mounting structure 10 for a superconductor device according to the present invention. The mounting structure 10 is contained in the device holding apparatus 1 shown in FIG. 13, when the superconductor device 4 is operated under the specific condition, i.e., at the pressure of 2�10−2 Pa or less in the closed vacuum chamber shown in FIG. 13 and at the temperature of 80 K or less.
The conductive layer 17 is made of a material having a specific resistance ρ less than 3 μΩ�cm and a modulus of elasticity more than 5�106 psi and less than 20�106 psi, for example, a metal selected from among the group consisting of gold, silver, copper, aluminum and an alloy made of at least one of gold, silver, copper and aluminum.
EXAMPLE It will be described hereinlater that results of measurement of the filter function of the above filter 11 in the mounting structure 10 shown in FIGS. 1 and 2 with reference to the following Table 1. The measurement was performed after the preparation having the steps as follows:
(a) mounting the filter 11 on the device holder 14 by way of the conductive layer 17 at a room temperature of 300 K and a pressure of 1�105 Pa;
(d) evacuating an air from the vacuum chamber to have the pressure held at a pressure of 2�10−2 Pa or less;
In the mounting structure 10, the filter function of the filter 11 and the amount of the released gas were measured, when the filter 11 was fastened by the fastening parts 15 at the contact pressures of 0.01, 0.05, 0.5, 5.0 and 20.0 kg/cm2. The attenuation A and the quantity, �Q� of the released gas were measured at each of the above contact pressures in accordance with a following equation (1):
Q(Pa�m 3/sec)=(P t −P 0)�V/t (1) wherein: V is a volume (m3) of the vacuum chamber which is 0.005 m3; P0 is a pressure which was measured when the steps (a) to (c) were bypassed and after the steps (d) to (f) were performed; and Pt is a pressure which was measured after performing the steps (a) to (f) and then after passing a time t of 50 hours.
3 � 10−10 4 � 10−10 6 � 10−10 8 � 10−10 6 � 10−8 Gas Q
It will be appreciated from the above results that the mounting structure 10 according to the present invention can ensure that the released gas is restricted within 1�10−9 Pa�m3/sec and the attenuation A is 90 dB or more when the contact pressure is defined between 0.05 and 5.0 kg/cm2. Therefore, the mounting structure 10 according to the present invention can adjust the contact pressure ranging between 0.05 and 5.0 kg/cm2 enough to stably ground the filter 11.
9 � 10−10 1 � 10−9 5 � 10−9 7 � 10−8 5 � 10−7 Gas Q
The filter 11 is generally required to have the quantity Q of the gas released therefrom reduced to 1�10−9 Pa�m3/sec or less as described above. The quantity Q of the gas released from the filter 11, however, exceeds 1�10−9 Pa�m3/sec when the filter 11 is fastened by the fastening parts 15 at the contact pressure of 5.0 kg/cm2 or more. This means that the control of the mounting structure, in which the conductive layer 17 is replaced with the adhesive layer made of an indium foil, fails to achieve both of requirements in the attenuation A and the quantity Q of the released gas.
Referring now to FIGS. 7 and 9 of the drawings, there is shown a second embodiment of the mounting structure 20 for the superconductor device according to the present invention. In this embodiment, the mounting structure 20 is adaptable for mounting a planer band-pass filter 21 and contained in the device holding apparatus 1 shown in FIG. 13, when the superconductor device 4 is operated under the specific condition, i.e., at the pressure of 2�10−2 Pa or less in the closed vacuum chamber and at the temperature of 80 K or less.
The device holder 24 has a base surface 24 a and is adapted to hold the filter 21 thereon. The device holder 24 is grounded where the filter 21 is electrically connected to the base surface 24 a of the device holder 24 through the conductive layer 27. As shown in FIG. 8, the base surface 24 a is formed on an upper side surface of the device holder 24 into a smoothed flat plane. The device holder 24 is made of a conductive material selected from among the group consisting of copper and aluminum. The device holder 24 is covered with a nickel and gold to form the base surface 24 a. The input connector 16 a is electrically connected to the filter 21 and the first external device through the input connector 5 shown in FIG. 13 to allow the signal to be inputted from the first external device to the filter 21. The output connector 16 b is electrically connected to the filter 21 and the second external device through the output connector 6 shown in FIG. 13 to allow the signal to be outputted from the filter 21 to the second external device. The filter 21 can thus transmit the signal from and to the first and second external devices outside of the device holding apparatus 1.
Each of the first, second and third conductive layers 27 a, 27 b and 27 c is made of a material having a specific resistance ρ less than 3 μΩ�cm and a modulus of elasticity more than 5�106 psi and less than 20�106 psi, for example, a metal selected from among the group consisting of gold, silver, copper, aluminum and an alloy made of at least one of gold, silver, copper and aluminum. Each of the first, second and third conductive layers 27 a, 27 b and 27 c may be formed into a shape selected from among the group consisting of a foil, a film, and a bump.
The fastening parts 15 are adapted to resiliently fasten the filter 21 to the device holder 24 to exert a predetermined pressing force Fa on the filter 21, so that the first surface of the first conductive layer 27 a can be held in press contact with the ground layer of the filter 21 and the second surface of the first conductive layer 27 a can be also held in press contact with the base surface 24 a of the device holder 24. This results in the fact that the ground layer of the filter 21 can be electrically connected to the device holder 24 through the first conductive layer 27 a. In this embodiment, the filter 21 has a circuit portion on which there is the circuit layer 23, a peripheral non-circuit portion on which there is no circuit layer, a central non-circuit portion on which there is also no circuit layer, and a gap non-circuit portion which is positioned between the input and output terminals of the filter 21 and on which there is also no circuit layer. The contact areas of the first conductive layer 27 a are arranged along the peripheral non-circuit portion of the filter 21. The fastening parts 15 are arranged along the peripheral portion of the device holder 24 at six points at the same places of the contact areas of the first conductive layer 27 a as shown in FIG. 7. The circular contact area of the second conductive layer 27 b is positioned on the central non-circuit portion of the filter 21, while the contact areas of the third conductive layer 27 c are arranged along the gap non-circuit portion of the filter 21.
The plate spring 28 g has a circular fixing portion having a center, at which the plate spring 28 g is secured to the cylindrical pressing member 28 b with a clamp screw 28 e, to have the center axis of the cylindrical pressing member 28 b parallel with the center axis of the clamp screw 28 e. The plate spring 28 g further has a plurality of spring portions along its peripheral portion outwardly extending from the circular fixing portion in the radial direction of the center axis of the cylindrical pressing member 28 b. The plate spring 28 g of the filter case 28 thus constructed is adaptable to resiliently fasten the filter 21 to the device holder 24 through the second conductive layer 27 b to exert a predetermined pressing force Fb on the filter 21.
This results in the fact that the fastening parts 15, the pressing member 28 b, and the springs 28 j are operated to exert the pressing forces Fa′, Fb and Fb′ to have the filter 21 held in press contact with the device holder 24 at the contact pressure ranging between 0.05 and 5 kg/cm2 on the corresponding contact areas of the first, second and third conductive layers 27 a, 27 b and 27 c, respectively. The contact pressure of each of the plate springs 15 a, 28 g and 28 j is defined to be between 0.05 and 5 kg/cm2 on the corresponding contact areas of the first, second and third conductive layers 27 a, 27 b and 27 c. Accordingly, the mounting structure 20 according to the present invention can adjust the contact pressure ranging between 0.05 and 5 kg/cm2 enough to stably ground the filter 21. As a result, the ground layer of the; filter 21 can be securely grounded enough to have an extremely low contact resistance. Moreover, the mounting structure 20 can have the amount of the released gas restricted within 1�10−9 Pa�m3/sec.
Referring now to FIGS. 10 and 11 of the drawings, there is shown a third embodiment of the mounting structure 30 for the superconductor device according to the present invention. In this embodiment, the mounting structure 30 is adaptable for mounting a pair of planer band-pass filters 31 a and 31 b and contained in the device holding apparatus 1 shown in FIG. 13, when the superconductor device 4 is operated under the specific condition, i.e., at the pressure of 2�10−2 Pa or less in a closed vacuum chamber and at the temperature of 80 K or less.
The pair of filters 31 a and 31 b is arranged next to each other as shown in FIGS. 10 and 11. The filters 31 a and 3 b are identical to each other. Therefore, the filters 31 a and 31 b are representatively referred to as �the filter 31� in the following description when it is unnecessary to distinguish between the filters 31 a and 31 b. The filter 31 is adapted to have a signal inputted from a first external device (not shown in the drawings) to output a second external device (not shown). The filter 31 should have a filter function in frequency response defined as the attenuation A of 90 dB or more. As shown in FIGS. 10 and 11, the filter 31 comprises a dielectric substrate 32 having first and second surfaces 32 a and 32 b diametrically opposite to each other and a circuit layer 33. The circuit layer 33 has a pattern of circuit made of a superconducting thin film on the first surface 32 a of the dielectric substrate 32 to allow the inputted signal to pass therethrough. The first surface 32 a of the dielectric substrate 32 is shown in FIG. 11 as being an upper side surface, while the second surface 32 b of the dielectric substrate 32 is shown in FIG. 11 as being a lower side surface.
The device holder 34 has a base surface 34 a and is adapted to hold the filter 31 thereon. The device holder 34 is grounded where the filter 31 is electrically connected to the base surface 34 a of the device holder 34 through the conductive layer 37. As shown in FIG. 11, the base surface 34 a is formed on an upper side surface of the device holder 34 into a smoothed flat plane. The device holder 34 is made of a conductive material selected from among the group consisting of copper and aluminum. The device holder 34 is covered with a nickel and gold to form the base surface 34 a. Each of the filters 31 a and 31 b is provided with the input and output connectors 16 a and 16 b. For example, the input connector 16 a is electrically connected to the filter 31 a and the first external device through the input connector 5 shown in FIG. 13 to allow the signal to be inputted from the first external device to the filter 31 a. The output connector 16 b is electrically connected to the filter 31 a and the second external device through the output connector 6 shown in FIG. 13 to allow the signal to be outputted from the filter 31 a to the second external device. The filter 31 a can thus transmit the signal from and to the first and second external devices outside of the device holding apparatus 1. The filter 31 b is also can transmit the signal from and to the other external devices outside of the device holding apparatus through the similar manner.
Each of the first and second conductive layers 37 a and 37 b is made of a material having a specific resistance ρ less than 3 μΩ�cm and a modulus of elasticity more than 5�106 psi and less than 20�106 psi, for example, a metal selected from among the group consisting of gold, silver, copper, aluminum and an alloy made of at least one of gold, silver, copper and aluminum. Each of the first and second conductive layers 37 a and 37 b may be formed into a shape selected from among the group consisting of a foil, a film, and a bump.
The fastening parts 15 are adapted to resiliently fasten the filter 31 to the device holder 34 to exert a predetermined pressing force Fa″ on the filters 31, so that the first surface of the first conductive layer 37 a can be held in press contact with the ground layer of the filter 31 and the second surface of the first conductive layer 37 a can be also held in press contact with the base surface 34 a of the device holder 34. This results in the fact that the ground layer of the filter 31 can be electrically connected to the device holder 34 through the first conductive layer 37 a. In this embodiment, the filter 31 has a circuit portion on which there is the circuit layer 33, and outside and inside peripheral portions on which there is no circuit layer. The inside peripheral portions of the filters 31 a and 31 b are arranged face to face with each other. The contact areas of the first conductive layer 37 a are arranged along the outside peripheral portion of the filters 31 a and 31 b, while the contact areas of the second conductive layer 37 b are arranged along the inside peripheral potions of the filters 31 a and 31 b. The fastening parts 15 are arranged along the peripheral portion of the device holder 34 at ten points at the same places of the contact areas of the first conductive layer 37 a as shown in FIG. 10.
This results in the fact that the fastening parts 15 and the separating and pressing member 38 b are operated to exert the pressing forces Fa″ and Fc to have the filter 31 held in press contact with the device holder 34 at the contact pressure ranging between 0.05 and 5 kg/cm2 on the corresponding contact areas of the first and second conductive layers 37 a and 37 b. The contact pressure of each of the plate springs 15 a and 38 c is defined to be between 0.05 and 5 kg/cm2 on the corresponding contact areas of the first and second conductive layers 37 a and 37 b. Accordingly, the mounting structure 30 according to the present invention can adjust the contact pressure ranging between 0.05 and 5 kg/cm2 enough to stably ground the filter 31. As a result, the ground layer of the filter 31 can be securely grounded enough to have an extremely low contact resistance. The mounting structure 30 can have the amount of the released gas restricted within 1�10−9 Pa�m3/sec.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS5057877 *Oct 26, 1990Oct 15, 1991At&T Bell LaboratoriesSuperconductor interconnection apparatusUS5936401 *Sep 19, 1996Aug 10, 1999The United States Of America As Represented By The Secretary Of The Air ForceDevice and process for measuring electrical properties at a plurality of locations on thin film superconductorsUS6108214 *Dec 30, 1998Aug 22, 2000Advanced Mobile Telecommunication Technology, Inc.Mounting structure of superconducting circuit* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS7729129Oct 17, 2007Jun 1, 2010Fujitsu LimitedMounting device for high frequency microwave devicesUS8067837 *Jun 17, 2005Nov 29, 2011Megica CorporationMetallization structure over passivation layer for IC chipUS8198729 *Jul 18, 2005Jun 12, 2012Megica CorporationConnection between a semiconductor chip and a circuit component with a large contact areaUS8742582Oct 11, 2011Jun 3, 2014Megit Acquisition Corp.Solder interconnect on IC chipEP1986244A2 *Nov 12, 2002Oct 29, 2008Fujitsu LimitedMounting structureWO2004075338A1 *Dec 18, 2003Sep 2, 2004Cao BisongSuperconductive microstrip resonator and filterWO2013190349A1 *Jun 17, 2013Dec 27, 2013Tel Solar AgRf feed line* Cited by examinerClassifications U.S. Classification174/70.00R, 505/220, 257/E39.002, 257/661, 257/700, 174/125.1, 257/726International ClassificationH01L39/22, H01L39/02, H01P3/08, H01P1/203, H01L39/04Cooperative ClassificationH01P1/20372, H01L39/04European ClassificationH01L39/04, H01P1/203C2CLegal EventsDateCodeEventDescriptionJan 19, 2010FPExpired due to failure to pay maintenance feeEffective date: 20091127Nov 27, 2009LAPSLapse for failure to pay maintenance feesJun 8, 2009REMIMaintenance fee reminder mailedMay 5, 2005FPAYFee paymentYear of fee payment: 4Dec 29, 1998ASAssignmentOwner name: ADVANCED MOBIL TELECOMMUNICATION TECHNOLOGY INC.,Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HOSHIZAKI, HIROKI;FUSE, MASASHI;REEL/FRAME:009695/0193Effective date: 19981210RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google