JP2002026656A - Saw oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a SAW oscillator that attains downsizing and a low profile and realizes high frequency processing and highly stable performance by minimizing the effect of a heat from an IC onto a SAW resonator contained in one package. SOLUTION: In the SAW oscillator where a SAW resonator 25 consisting of an IDT 28 having a couple of interdigital electrodes and of reflectors 29a, 29b placed at both sides of the IDT 28 in its length direction that are formed on the major side of a piezoelectric substrate 27 and an IC chip 26 having an oscillation circuit driving the SAW resonator 25 are adhered onto a mount face of a common base 23 in one package, the IC chip is fixed on a conductor pattern 32 on the package mount side extended up to a rear side of the package as a ground terminal at one side of the SAW resonator in the length direction, and the SAW resonator is fixed by means of a cantilever at a rear side of an area where no IDT is at least in existence at one end 25a remoter from the IC chip in the length direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor IC such as an IC chip having a SAW resonator and an oscillation circuit for driving the SAW resonator, which is used in various communication devices such as a cellular phone.
The present invention relates to a SAW oscillator in which elements are housed in the same package.

[0002]

2. Description of the Related Art In recent years, in order to cope with an increase in communication speed accompanying rapid development of information communication technology and network technology, an oscillator used in communication equipment has been required to have a higher frequency and a higher stability. As an oscillator suitable for high frequency operation, a SAW oscillator including a SAW resonator using a surface acoustic wave (SAW) and an IC chip in which an oscillation circuit for driving the SAW resonator is integrated is widely used. . Furthermore, in order to meet the demand for smaller and thinner communication devices such as mobile phones, in order to achieve further miniaturization, SA
A SAW oscillator that accommodates a W resonator and an IC chip in the same package has been developed.

FIGS. 7 and 8 show a typical example of a SAW oscillator according to the prior art. A SAW resonator 2 and a monolithic IC chip 3 are electrically nonconductive on a rectangular plate-shaped metal base 1 on the entire back surface. And the lid 4 is sealed by resistance welding or the like. In the vicinity of each corner of the base 1, there are provided leads 5 for connection to an external circuit and ground.
8 penetrate and bond pads 9 on the IC chip 3
And a bonding wire 10 respectively. The SAW resonator 2 has a reflector 1 in its longitudinal direction.
A bonding pad 13 pulled out from an interdigital electrode (IDT) 12 composed of a set of comb-shaped electrodes disposed between the electrodes 1 and 11 is similarly electrically connected to the bonding pad 9 of the IC chip 3 by a bonding wire 14. ing.

Japanese Unexamined Patent Publication No. 2-290308 discloses that in a SAW oscillator in which a SAW resonator and an IC chip are housed in the same package, the bonding pad of the SAW resonator is replaced with the bonding pad of the IC chip. By arranging the SAW resonators so as to face each other in parallel with the SAW propagation direction, the length of the bonding wires electrically connecting the SAW resonators is made sufficiently short, and the influence of the parasitic inductance and electromagnetic induction is reduced to oscillate. There is disclosed a configuration that stabilizes the operation and reduces the possibility that the bonding wire is cut or disconnected.

[0005]

Generally, a SAW device using a surface acoustic wave, like other piezoelectric devices,
It has a temperature characteristic whose resonance frequency changes subtly with temperature. On the other hand, in general, the amount of heat generated by a semiconductor element increases as the operating frequency increases, so that the SAW device housed in the same package may be affected by the heat generation and the resonance frequency may fluctuate. Further, since the SAW device has a different coefficient of thermal expansion from the package to which the SAW device is bonded and fixed, when the semiconductor element bonded and fixed to the same package generates heat, the stress caused by the difference in the coefficient of thermal expansion causes the SAW device to lose its stress. And may change the resonance frequency of the SAW device.

[0006] However, as described in the above-mentioned Japanese Patent Application Laid-Open No. 2-290308, the conventional SAW oscillator described above has been thoroughly examined for the optimum configuration such as the arrangement of chips and the wiring method between chips. In the SAW oscillators of FIGS. 7 and 8, heat from the IC chip 3
It easily transmits to the temperature sensitive IDT 12 via the adhesive on the metal base 1 and the back surface of the SAW resonator 2. In particular, the SAW oscillator disclosed in this patent publication has a problem in that the SAW element and the IC element are close to each other and are directly connected by a sufficiently short bonding wire.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a SAW oscillator in which a SAW resonator and an IC element are housed in the same package. It is an object of the present invention to provide a structure capable of minimizing the influence of heat generated on a SAW resonator and realizing a high frequency and a high stability of performance while meeting the demand for miniaturization and thinning.

[0008]

According to the present invention, in order to achieve the above object, an interdigital electrode (IDT) comprising at least one pair of comb-shaped electrodes and reflectors arranged on both sides in the longitudinal direction of the interdigital electrode are provided. A SAW resonator formed on a main surface of a substrate and an IC element having an oscillation circuit for driving the SAW resonator are fixed on a common mounting surface in the same package. Is fixed on a metal pattern formed on the package mounting surface and extending so as to be exposed on the outer surface of the package, on one side along the longitudinal direction, and the SAW resonator is disposed in the longitudinal direction remote from the IC element. A SAW oscillator is provided at one end thereof, which is fixed in a cantilever manner at least on the back surface of the region where the interdigital electrode is not present.

With this configuration, the heat generated from the IC element can be efficiently radiated at least partially from the package mounting surface to the outside of the package via the metal pattern, and furthermore, from the IC element via the package. Since the heat transfer path of the SAW resonator, particularly to the temperature-sensitive IDT, can be lengthened, and the heat transfer area from the package to the SAW resonator can be reduced.
The influence on the resonance frequency of the AW resonator can be significantly reduced as compared with the related art.

Further, when the SAW resonator is mounted in a cantilever manner at one end thereof, the change in resonance frequency and the amount of deformation of the piezoelectric substrate are smaller than when the SAW resonator is bonded on the entire back surface. For example, Japanese Patent Application Laid-Open No.
It is already known in JP-A-3303082. In addition to this, according to the present invention, by mounting the SAW resonator in a cantilever manner in an area where the IDT does not exist, the SAW resonator has an influence on its resonance frequency.
It is possible to eliminate the possibility that a stress due to a difference in thermal expansion coefficient between the W resonator and the package acts.

In one embodiment, the metal pattern of the package is a conductor connected to an electrode of the IC element, and an extension of the metal pattern exposed on the outer surface of the package is a connection terminal to an external circuit. This is advantageous because heat from the IC element can be further released through an external circuit, and the heat radiation effect is further improved, and the wiring and structure of the package can be simplified.

In one embodiment, the SAW resonator and the IC element are electrically connected via a conductor pattern formed on a package. As a result, heat is directly transmitted from the IC element to the SAW resonator as compared with the case where the SAW resonator and the IC element are directly connected by a bonding wire using a gold wire or an aluminum wire having relatively high thermal conductivity. This is convenient because it is not transmitted.

When this conductor pattern is connected to another metal pattern exposed on the outer surface of the package so as to be able to transfer heat through, for example, a thermal via hole or the like, at least heat that can be transferred from the IC element to the SAW resonator. Since a part is released to the outside through the other metal pattern, the heat radiation effect is further improved and the possibility of affecting the SAW resonator is reduced. Further, it is preferable that another metal pattern be a connection terminal to an external circuit, since the wiring and structure of the package can be similarly simplified.

In one embodiment, an electrode for connecting the interdigital electrode of the SAW resonator to an electrode of the IC element has an area corresponding to the longitudinal end for fixing the SAW resonator on a package mounting surface. It is arranged in. When the electrode of this SAW resonator is formed as a bonding pad on the main surface of the piezoelectric substrate, the SA corresponding to the bonding pad is formed.
Since the back surface of the W resonator is fixed to the package mounting surface, the ultrasonic energy applied to connect the gold wire and the aluminum wire to the W resonator does not leak out, and they can be bonded sufficiently. Nature can be secured.

In this case, all the bonding pads are
If the SAW resonator is arranged on one side along the longitudinal direction, the area for fixing the SAW resonator to the package mounting surface can be correspondingly reduced, thereby reducing heat from the IC element. This is preferable because the transmission area can be reduced and the influence of stress due to the difference in the coefficient of thermal expansion can be reduced.

Further, all the bonding pads are SA
If they are arranged on the side near the IC element along the longitudinal direction of the W resonator, the bonding wires connected to them can be made shorter, so that the bonding wires may be deformed or come off due to vibration or impact. And the reliability of the oscillator is improved.

Still further, the bonding pad from the comb-shaped electrode remote from the IC element of the interdigital electrode can draw out the reflector as an intermediate conductor, thereby forming a conductor pattern on the piezoelectric substrate that bypasses the reflector. It is not necessary to wire the electrodes, the electrode pattern can be easily formed on the piezoelectric substrate, and the conductor resistance of the lead wire can be suppressed to a relatively low level.

In another embodiment, an electrode of a SAW resonator is formed on the back surface of a piezoelectric substrate as an extraction electrode from an IDT, and an anisotropic conductive adhesive is used for a connection electrode formed on a package mounting surface. It can also be fixed. Also, this I
S formed on the back surface of the piezoelectric substrate as an extraction electrode from DT
A bump can be formed on the electrode of the AW resonator and fixed to the connection electrode on the base mounting surface using an adhesive.

In one embodiment, the output electrode of the IC element is located farther from the longitudinal end where the SAW resonator is fixed. Since an IC element having an oscillation circuit generates a large amount of heat particularly near its output terminal, it is
By setting the W resonator as far as possible from the fixed position on the package mounting surface, the influence of heat on the SAW resonator can be reduced.

On the contrary, since the amount of heat generated near the input terminal of the IC element is relatively small, in another embodiment, I
By arranging the electrode on the input side of the C element on the side near the longitudinal end where the SAW resonator is fixed, the influence of heat on the SAW resonator can be similarly reduced. In particular, further effects can be obtained by combining these arrangements of the input side and output side electrodes and separating them as far as possible.

In one embodiment, the package is vacuum-sealed to eliminate the possibility that heat from the IC element is transmitted to the SAW resonator by convection in the package or heat conduction by gas. .

Further, if the package is sealed with a gas having a lower thermal conductivity than air, even if a small leak occurs in the package, the invasion of corrosive gas from the outside can be prevented and the SAW resonance can be prevented. There is no danger of deteriorating the element and the IC element. In particular, when an inert gas such as argon, xenon, or krypton is filled, a higher effect can be obtained.

[0023]

FIG. 1 shows a preferred embodiment of a SAW oscillator according to the present invention. The surface-mounted SAW oscillator 20 according to the present embodiment has a package including a thin rectangular box-shaped base 23 and a lid 24 in which a frame 22 is integrally joined along the periphery of the upper surface of a substrate 21 made of an insulating material. An IC chip 2 in which a SAW resonator 25 and an oscillating circuit for driving the SAW resonator 25 are integrated is provided inside the package.
6 are mounted on a common base 23 mounting surface, and hermetically sealed by joining the lid 24 to the upper end of the frame 22 as shown in FIG.

The SAW resonator 25 has an IDT 28 composed of a pair of comb-shaped electrodes 28a and 28b on the main surface of a piezoelectric substrate 27 made of quartz, langasite, LBO, sapphire, diamond, etc. The arranged reflectors 29a and 29b are formed. The SAW resonator 25 is adhesively fixed at one end 25a in the longitudinal direction in a cantilever manner with the back surface of the SAW resonator 25 slightly lifted from the base mounting surface by an adhesive 30. This adhesive is preferably a conductive adhesive that can be used to prevent the piezoelectric substrate 27 from being charged or to bond the IC chip 26, thereby preventing the IC chip from being charged and preventing an unexpected potential from being generated. can do.

The main surface of the SAW resonator 25 corresponding to the area where the fixed side end 24a is bonded is provided with an IC chip 26 for electrically connecting the IDT to the IC chip.
The bonding pad 31a pulled out from the comb-shaped electrode 28a farther from the IC chip via one reflector 29a and the bonding pad 31b drawn from the comb-shaped electrode 28b closer to the IC chip are connected to the reflector 29a. It is formed on the side of the IC chip. Therefore, the SAW resonator 25 has bonding pads 31a,
SAW resonator 2 corresponding to a narrow area provided with 31b
5 is adhered to the base 23 on the back surface.

The IC chip 26 has a fixed end 25 at one side along the longitudinal direction of the SAW resonator 25.
a and farther from the free end 25b. The IC chip 26 is bonded and fixed on a conductive pattern 32 formed on the mounting surface of the base 23 by metallization such as metal deposition, for example, with a good heat conductive adhesive 33. The conductor pattern 32 is the IC chip 26
It has a dimension that is wide enough to mount the whole, and extends from the side surface to the back surface of the substrate 21 and is exposed on the outer surface of the base 23. On the upper surface of the IC chip 26, two bonding pads 34a and 34b are formed as input-side electrodes along the side closer to the fixed-side end 25a of the SAW resonator 25, and from the fixed-side end. Two bonding pads 35a and 35b are formed as output-side electrodes along the far side, and one bonding pad 36 as a ground electrode is formed along the side opposite to the SAW resonator. Is formed.

An IC chip 26 is mounted on the mounting surface of the base 23.
And two conductor patterns 37 on each side of the
a, 37b, 38a and 38b are SAW as intermediate conductors.
The resonator 25 is formed in parallel along the longitudinal direction.
These conductor patterns are formed on the input and output bonding pads 3 of the IC chip adjacent to one end.
4a, 34b, 35a, 35b and bonding wires 39a, 39b, 40 such as gold wires or aluminum wires.
a and 40b are electrically connected. The input-side conductor patterns 37a and 37b have opposite ends respectively corresponding to the bonding pads 31 of the SAW resonator 25.
a and 31b, and are similarly electrically connected by bonding wires 41a and 41b, respectively. The bonding pad 36 for grounding of the IC chip is connected to the conductor pattern 32 used as a ground terminal in this embodiment by a bonding wire 42.

Further, conductor patterns 43 and 44 are formed on the outer surface of the base 23 as output / control connection terminals for connection to an external circuit, for example, by metallization. In this embodiment, a conductor pattern 45 connected to a conductor pattern on the base mounting surface via a thermal via hole is formed on the outer surface of the base 23 as required. 2, a conductor pattern 37a as an intermediate conductor for connecting the SAW resonator and the IC chip is exposed on the back surface of the base 23 via a via hole 46 formed inside the substrate 21. And electrically and thermally conductively connected to a conductor pattern 45 as a control terminal. Other conductor patterns 37b, 38a, 3
8b, via a via hole or an inner layer circuit pattern similarly formed in the substrate 21, the corresponding base 23
It can be connected to the connection terminal on the outer surface.

The package constructed as described above is sealed in a vacuum by joining the lid 24 to the base 23 in a vacuum environment. As a result, there is no gas convection or heat conduction through the gas inside the package.
The heat from the C chip is more difficult to transmit to the SAW resonator. However, in the case of vacuum sealing, even if a slight leak occurs, corrosive gas enters the package and S
Since there is a possibility that the performance of the AW oscillator may be deteriorated, in another embodiment, the AW oscillator is sealed with a gas having a lower thermal conductivity than air, so that the intrusion of corrosive gas from the outside can be prevented. Such sealing gases include, for example, in particular, argon, xenon,
An inert gas such as krypton is preferred.

When the SAW oscillator shown in FIG. 1 is operated while being surface-mounted on a substrate, heat from the IC chip 26 is mainly transmitted from the output bonding pads 35a and 35b to the conductor patterns 38a and 38b as intermediate conductors and to the conductor patterns 38a and 38b. The light is emitted from the outer surface of the base 23 to the atmosphere through the connected conductor pattern 44 and to the outside through the circuit of the substrate connected thereto. Further, heat from the IC chip is radiated from the adhesive 33 and the grounding bonding pad 36 to the atmosphere from the outer surface of the base 23 via the conductor pattern 32 and to the outside via the circuit of the substrate connected to the conductor pattern 32. Is done. In addition, since the bonding area of the SAW resonator is small, the amount of heat transmitted from the IC chip to the SAW resonator in the package is greatly reduced, and at the same time, the stress caused by the difference in the coefficient of thermal expansion between the SAW resonator and the package is S.
The effect on the AW resonator is reduced.

FIG. 3 shows a modification of the SAW oscillator shown in FIG. In this embodiment, the bonding pads 31 from the comb electrodes 28a and 28b of the SAW resonator 25 are used.
a, 31b are respectively drawn out to both sides of the reflector 29a along the side of the adjacent piezoelectric substrate 27, so that S
The difference from the embodiment of FIG. 1 is that the AW resonator 25 is fixed by the adhesive 30 over the entire width of the fixed end portion 25a. Also in this case, the SAW resonator 25 is bonded to the base 21 in a range where the IDT 28 does not exist so as not to affect the resonance frequency.

Further, in another embodiment, the SAW resonator can be bonded to the base using an adhesive mixed with beads, so that the SAW resonator can be floated at an appropriate height from the mounting surface of the base. Can be. Further, an adhesive mixed with beads having a metal film formed on the surface can be used as an anisotropic conductive adhesive.

By applying the present invention, the SAW resonator is cantilevered at its fixed end in a package made of the same insulating material as in FIG. The IC chip is adhered to one side along the longitudinal direction of the SAW resonator at a position away from the fixed side end, and the package mounting surface A surface-mounted SAW oscillator having an oscillation frequency of 125 MHz, in which an IC chip and a SAW resonator were electrically connected to each other using the intermediate conductor and the bonding wire formed as described above, was manufactured. No thermal via hole was provided on the input side of the IC chip. As a comparative example, a conventional surface-mounted SAW oscillator having the same structure and having a SAW resonator bonded to the entire back surface was manufactured.

By operating these SAW oscillators, the SAW
When the temperature change of the resonator and the time change of the frequency of the SAW oscillator were measured, the results shown in FIGS. 4A and 4B were obtained, respectively. Further, these SAW oscillators were actually operated in a state of being surface-mounted on a substrate, and similarly, the temperature of the SAW resonator and the temporal change of the frequency of the SAW oscillator were measured. The results shown in FIGS. 5A and 5B were obtained. Was. 4 and 5
From the measurement results of the above, according to the present invention, the SAW
By configuring the oscillator, the heat of the IC chip
It can be seen that the effect on the resonator can be significantly reduced compared to the conventional case.

Further, as described above, the SAW resonator is bonded in a cantilever manner, and an IC chip is bonded on a conductor pattern extending to the outer surface of the package as in the embodiment of FIG.
A SAW oscillator hermetically sealed with a lid was manufactured. FIG.
The above-mentioned SAW oscillators related to the above were hermetically sealed with lids, and these were operated in the same manner, and the temporal changes in the temperature and frequency of the lids of the SAW oscillators were measured. FIG.
A shows the measurement results of the temperature of the lid of the SAW oscillator when the conductor pattern is provided and when the conductor pattern is not provided. FIG. 6B shows that S in those cases.
3 shows a temporal change of the frequency of the AW oscillator. From these results, it can be seen that the heat of the IC chip is effectively released to the outside of the package via the conductor pattern, and the influence on the SAW resonator can be reduced.

Although the preferred embodiment of the present invention has been described in detail, the present invention can be implemented by adding various modifications and changes to the above embodiment within the technical scope thereof. For example, instead of wire bonding, the IC chip can be connected to lands formed on the mounting surface of the base by flip chip bonding. Similarly, S
In the AW resonator, an extraction electrode from each comb electrode is formed on the back surface of the fixed side end of the piezoelectric substrate, and is fixed to a land or an electrode pad formed on the mounting surface of the base in a cantilever manner with a conductive adhesive. You can also.

[0037]

According to the SAW oscillator of the present invention, as described above, the heat generated from the IC element is efficiently radiated from the package mounting surface to the outside of the package via the metal pattern, and at the same time, the heat generated from the IC element is reduced. By extending the heat transfer path to the SAW resonator, especially to the IDT, and reducing the heat transfer area from the package to the SAW resonator, by supporting the SAW resonator in a cantilevered region in the absence of the IDT, In addition, since the effect of stress caused by the difference in the coefficient of thermal expansion between the SAW resonator and the package is greatly reduced, even if the amount of heat generated from the IC element increases due to the increase in the frequency, the effect on the resonance frequency of the SAW resonator is increased. Frequency, and high stability while responding to miniaturization and thinning of the SAW oscillator.

[Brief description of the drawings]

FIG. 1 is a partial sectional perspective view showing an embodiment of a SAW oscillator according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a plan view showing a modification of the SAW oscillator of FIG.

FIG. 4A is a diagram showing a temperature change of a SAW resonator in a SAW oscillator manufactured by applying the present invention, and FIG. 4B is a diagram showing a frequency change of the SAW oscillator in comparison with a conventional SAW oscillator. .

5A is a diagram showing a temperature change of a SAW resonator in a state where the SAW oscillator of FIG. 4 is surface-mounted on a substrate, and FIG. 5B is a diagram showing a frequency change of the SAW oscillator in comparison with a conventional SAW oscillator. It is.

FIG. 6A is a diagram showing the SAW of the SAW oscillator shown in FIG. 4 when an IC chip is bonded to a conductor pattern for heat radiation;
FIG. B is a diagram showing a change in temperature of the lid of the oscillator, and FIG. B is a diagram showing a change in frequency of the SAW oscillator in comparison with a case where no conductor pattern is provided.

FIG. 7 is a perspective view showing a conventional SAW oscillator.

8 is a sectional view taken along line VIII-VIII in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Metal base 2 SAW resonator 3 IC chip 4 Lid 5-8 Lead 9 Bonding pad 10 Bonding wire 11 Reflector 12 Cross finger electrode, IDT 13 Bonding pad 14 Bonding wire 20 SAW oscillator 21 Base 22 Frame 23 Package 24 Cover 25 SAW Resonator 25a Fixed-side end 25b Free-side end 26 IC chip 27 Piezoelectric substrate 28 IDT 28a, 28b Comb-shaped electrode 29a, 29b Reflector 30 Adhesive 31a, 31b Bonding pad 32 Conductive pattern 33 Adhesive 34a, 34b, 35a , 35b, 36 Bonding pads 37a, 37b, 38a, 38b Conductive patterns 39a to 41a, 39b to 41b, 42 Bonding wires 43 to 45 Conductive patterns 46 Via holes

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5J079 AA07 BA43 FA01 HA06 HA22 HA25 JA03 KA05 5J097 AA30 BB01 DD24 HA05 JJ01 JJ03 KK07 KK10 LL03 LL08

Claims (15)

[Claims] 1. A SAW resonator in which at least one pair of interdigital electrodes comprising comb electrodes and reflectors disposed on both sides in the longitudinal direction are formed on a main surface of a piezoelectric substrate, and an oscillation circuit for driving the SAW resonator. A SAW oscillator having an IC element having the same fixed on a common mounting surface in the same package, wherein the IC element is provided on one side of the SAW resonator along a longitudinal direction of the SAW resonator. The SAW resonator is fixed on a metal pattern formed on the mounting surface and extending so as to be exposed on the outer surface of the package, wherein the SAW resonator has at least the intersection at a longitudinal end remote from the IC element. A SAW oscillator fixed in a cantilever manner on the back surface of a region where no finger electrode is present. 2. The semiconductor device according to claim 1, wherein the metal pattern is a conductor connected to an electrode of the IC element, and a portion of the metal pattern exposed on an outer surface of the package is a connection terminal to an external circuit. 2. The SAW oscillator according to 1. 3. The SAW oscillator according to claim 1, wherein the SAW resonator and the IC element are electrically connected via a conductor pattern formed on the package. 4. The SAW oscillator according to claim 3, wherein the conductor pattern is connected to another metal pattern exposed on an outer surface of the package so as to be able to transfer heat. 5. The SA according to claim 4, wherein the another metal pattern is a connection terminal to an external circuit.
W oscillator. 6. An electrode for connecting the interdigital electrode of the SAW resonator to an electrode of the IC element is arranged in a region corresponding to the longitudinal end for fixing the SAW resonator on the package mounting surface. The SAW oscillator according to claim 1, wherein the SAW oscillator is provided. 7. The electrode according to claim 6, wherein the electrode for connecting the interdigital electrode of the SAW resonator to the electrode of the IC element is a bonding pad formed on a main surface of the piezoelectric substrate. The described SAW oscillator. 8. The SAW oscillator according to claim 7, wherein all the bonding pads are arranged on one side along a longitudinal direction of the SAW resonator. 9. The SAW oscillator according to claim 8, wherein all the bonding pads are arranged on a side closer to the IC element along a longitudinal direction of the SAW resonator. 10. The method according to claim 7, wherein the bonding pad of the interdigital electrode, which is farther from the IC element than the IC element, is led out using the reflector as an intermediate conductor. 3. The SAW oscillator according to claim 1. 11. The device according to claim 1, wherein an electrode on the output side of the IC element is arranged on a side farther than the longitudinal end portion fixing the SAW resonator. SAW oscillator. 12. The device according to claim 1, wherein an electrode on the input side of the IC element is arranged on a side close to the longitudinal end for fixing the SAW resonator. SAW oscillator. 13. The SAW oscillator according to claim 1, wherein said package is vacuum-sealed. 14. The SAW oscillator according to claim 1, wherein the package is sealed with a gas having a lower thermal conductivity than air. 15. The SAW oscillator according to claim 14, wherein the gas is an inert gas containing argon, xenon, or krypton.