Patent US695352A successfully refreshed from Google Patents.
Patent EP0909024A2 successfully refreshed from Google Patents.
EP0909024A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Impedance matching device
Assignee: Sharp Corp
•
Filing: 1998-09-09
•
Granted: —
•
Expires: 2018-09-09
Abstract
Abstract An impedance matching device includes a variable capacitor constituted by a non-linear dielectric thin film and an upper electrode disposed on a lower electrode formed on a substrate. The non-linear dielectric thin film is formed by a deposition, screen-printing, electroplating, or other technique, and changes its relative dielectric constant according to applied voltage. Therefore, the capacity of the variable capacitor is controlled and the impedance is matched, by simply controlling the applied voltage across the non-linear dielectric thin film. Consequently, the arrangement makes it possible to cut down the impedance matching device in size and cost, compared to an arrangement incorporating a capacitor and a coil for adjustment, effects a much simpler matching operation, and facilitates a manufacturing process.
Inventors
- 👤 Masumi Nakamichi
- 👤 Yoshiyuki Masuda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 14:42
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/38
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
105 words
An impedance matching device (1) mounted on a
high frequency circuit substrate, being characterised in
that said device comprises: a voltage-controlled variable capacitor (4), for
receiving an input signal, including, a non-linear dielectric thin film (5) having a
relative dielectric constant in accordance with a
strength of an applied electric field, a first electrode (6) formed on one of the
sides of the non-linear dielectric thin film (5),
and a second electrode (7) formed on the opposite
side of the non-linear dielectric thin film (5); and a control voltage application section (31) for
applying a control voltage across the first and second
electrodes (6, 7).
Claim 2
Dependent Claim
39 words
The impedance matching device (1) as set forth in
claim 1, wherein the non-linear dielectric thin film (5) is
made of BaTiO 3 , SrTiO 3 , or Ba x Sr 1-x TiO 3 (0 < x < 1).
Claim 3
Dependent Claim
29 words
The impedance matching device (1) as set forth in
claim 2, wherein the non-linear dielectric thin film (5) has
a uniform thickness in a range of 0.05µm to 10µm.
Claim 4
Dependent Claim
43 words
The impedance matching device (1) as set forth in
any one of claims 1 to 3, wherein the non-linear dielectric thin film (5) is
formed directly on a high frequency circuit substrate
(14) made of a dielectric ceramic substrate or a glass
substrate.
Claim 5
Dependent Claim
44 words
The impedance matching device (1) as set forth in
claim 4, wherein the non-linear dielectric thin film (5) is
formed directly on the high frequency circuit substrate
(14) by a deposition technique, a printing technique, or
a sol-gel technique using an organic metal salt.
Claim 6
Dependent Claim
26 words
The impedance matching device (1) as set forth in
claim 5, wherein the non-linear dielectric thin film (5) is
formed (14) by a photo etching technique.
Claim 7
Dependent Claim
20 words
The impedance matching device (1) as set forth in
claim 6, wherein the photo etching technique is a lift-off
technique.
Claim 8
Dependent Claim
36 words
The impedance matching device (1) as set forth in
claim 1, wherein the non-linear dielectric thin film (5) is
made of Ba x Sr 1-x TiO 3 (0 < x < 1) by a sol-gel technique.
Claim 9
Dependent Claim
44 words
The impedance matching device (1) as set forth in
any one of claims 4 to 6, wherein the non-linear dielectric thin film (5) has
an outer circumferential edge covered with an insulating
film (17) made of a material having a low relative
dielectric constant.
Claim 10
Dependent Claim
27 words
The impedance matching device (1) as set forth
in claim 9, wherein the insulating film (17) is made of SiO 2 or
Al 2 O 3 .
Claim 11
Dependent Claim
38 words
The impedance matching device (1) as set forth
in any one of claims 1 to 3, wherein the non-linear dielectric thin film (5) is
formed on a high frequency circuit substrate (14) by a
ceramic green sheet process.
Claim 12
Dependent Claim
40 words
The impedance matching device (1) as set forth
in any one of claims 1 to 11, wherein the first and second electrodes (6, 7) each
are a thick film conductive body formed with a skin
thickness thereof taken into consideration.
Claim 13
Dependent Claim
30 words
The impedance matching device (1) as set forth
in claim 12, wherein the first and second electrodes (6, 7) each
are made of a laminated layer of Pt and Ta.
Claim 14
Dependent Claim
49 words
The impedance matching device (1) as set forth
in claim 1, wherein the voltage-controlled variable capacitor
(4) compensates, using part of a change in a capacity
caused by a change in a relative dielectric constant of
the non-linear dielectric thin film (5), for an
irregularity in design and manufacture.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.