CN1333523C

CN1333523C - Time-frequency component manufacturing method and its products

Info

Publication number: CN1333523C
Application number: CNB021488878A
Authority: CN
Inventors: 颜文成
Original assignee: Taitien Electronics Co Ltd
Current assignee: Taitien Electronics Co Ltd
Priority date: 2002-11-22
Filing date: 2002-11-22
Publication date: 2007-08-22
Anticipated expiration: 2022-11-22
Also published as: CN1503449A

Abstract

The invention provides a manufacturing method of a time-frequency element, which comprises the steps of firstly electrically connecting a contact on a chip with a pin on a substrate by a flip chip packaging method in the substrate, then adhering one end of an oscillator on the side wall of the substrate by conductive adhesive in a vacuum environment, adjusting the oscillation frequency of the oscillator by a quality fine adjustment step, and finally sealing the substrate to finish packaging. In addition, the invention also provides a time-frequency element product, which comprises a substrate with an opening, a sealing cover for sealing the opening, a chip and an oscillator arranged in the substrate, and a frequency fine-tuning particle layer formed on the surface of the oscillator.

Description

The manufacture method of time-frequency elements and goods thereof

Technical field

The present invention relates to a kind of time-frequency elements, particularly relate to the time-frequency elements of the little and tool precise frequency of a kind of volume.

Background technology

Time-frequency elements, just so-called crystal oscillator (crystal oscillator), usually being widely used as in many electronic installations and communication device provides reference frequency (reference frequency) and the element of reference time (reference time), in recent years, more since portable apparatus (as mobile phone, PDA) rise, make the volume of time-frequency elements more become meticulous because of cooperating portable apparatus, on the other hand, except the little requirement of volume, more can not ignore on the frequency of time-frequency elements and the accuracy of time, therefore, need to take into account the processing procedure of said two devices, can obtain the good time-frequency elements of quality.

As shown in Figure 1, it is the circuit diagram of a time-frequency element 7, a common time-frequency elements 7 has comprised a chip 71, reach vibration 72, because vibration 72 is made with piezoelectricity (quartz) material, can't be integrated in the chip 71, therefore occur in external mode usually, then comprise the oscillating circuit of forming such as electronic components such as inverter, resistance 73 in the chip 71.

General time-frequency elements; as shown in Figure 2; be in substrate 82 with an opening 81; vibration son 83 and chip 84 that placement arranged side by side has encapsulated; be formed with circuit layout (not shown) on the substrate 82 with plural pin; and the method for utilizing line to engage (wire-bonding) makes the vibration son 83 and the chip 84 that have encapsulated electrically connect with these pins; then in substrate 82, insert colloid 85; by vibration son 83 and the chip 84 extended plain conductors of colloid 85 protection after this encapsulation, make a time-frequency element 8 after utilizing a loam cake 86 with these substrate 82 cappings at last.But, above said manufacture method, several shortcomings below but existing:

1. will vibrate respectively son and chip of the method for utilizing line to engage is electrically connected on the circuit layout of substrate, need insert a large amount of colloids and can prevent moisture by outside invasion, to avoid the plain conductor oxidation.

2. the son that will vibrate is inserted in the substrate after the encapsulation earlier again, and manufacturing cost is higher, and vibration after encapsulation can't adjust its quality and frequency, makes that the accuracy of time-frequency elements is lower.

3. because vibration is to place side by side with chip level, make that the volume of time-frequency elements integral body is bigger, can't reach the minimized requirement of volume.

Summary of the invention

Therefore, purpose of the present invention is providing a kind of time-frequency elements manufacture method of fine-tuning calibration frequency of oscillation.

Another object of the present invention is providing a kind of frequency of oscillation accurate time-frequency elements.

A further object of the present invention is providing a kind of volume little and only need insert the time-frequency elements of part colloid.

So, the present invention makes the method for time-frequency elements, wherein this time-frequency elements has a substrate, this substrate comprises a diapire that is formed with a circuit layout, and around this a diapire periphery and a upwardly extending sidewall, and this diapire matches with this sidewall and defines the accommodation space with an opening, this circuit layout is formed with plural pin at this diapire in the face of on the end face of this accommodation space, this method comprises step: (a) chip with plural contact is inserted this accommodation space by this opening, and with this chip respectively should the plural number contact and respectively this corresponding pin of this substrate diapire electrically connect; (b) under a vacuum environment, an end of a vibration son is arranged on the sidewall of this substrate to and electric connection corresponding with this chip; And (c) under this vacuum environment, seal the above-mentioned opening of this substrate that sub and this chip of this vibration is set with a capping, keep this accommodation space in a vacuum tight state whereby.

A kind of time-frequency elements of the present invention, include: a substrate, have a diapire and a upwardly extending sidewall of a periphery from this diapire, this diapire matches with this sidewall and defines the accommodation space with an opening, and this diapire is formed with a circuit layout, and this circuit layout is formed with plural pin at this diapire in the face of on the end face of this accommodation space; One capping is connected on this sidewall away from an end of this diapire and seals the opening of this accommodation space, is the airtight conditions of an about vacuum or vacuum in this accommodation space; One chip is arranged in this accommodation space, and this chip has an oscillating circuit, and plural number and the corresponding contact of these pins; One vibration son is arranged in this accommodation space up and down accordingly with this chip, and this vibration is that oscillating circuit with this chip electrically connects mutually; And a frequency trim particle layer, being formed on the surface of this vibration, this frequency trim particle layer comprises the particle of plural each interval, to increase the quality of this vibration, reduces the frequency of oscillation of this vibration whereby.

Description of drawings

Fig. 1 is the circuit diagram of an existing time-frequency elements;

Fig. 2 is a stereogram, and the structure of this existing time-frequency elements is described;

Fig. 3 is a flow chart, and the manufacture method of time-frequency elements of the present invention is described;

Fig. 4 is a profile, illustrates a chip is inserted situation in the substrate;

Fig. 5 is a part of enlarged drawing, illustrates that the contact of chip and the pin on the substrate are by the interconnective situation of a projection;

Fig. 6 is a profile, illustrates after this substrate is placed into this chip, connects the situation of vibration on a sidewall of this substrate;

Fig. 7 is a profile, and the situation of the plural particle of deposition on this vibration is described;

Fig. 8 is a profile, illustrates with a capping to seal the situation of making a time-frequency element behind this substrate.

Embodiment

Consult Fig. 3, the manufacturing process of time-frequency elements 1 preferred embodiment of the present invention comprises the following step:

Cooperate Fig. 4 and Fig. 5, wherein Fig. 5 is the part enlarged drawing of a-quadrant among Fig. 4, this time-frequency elements 1 has a substrate 11, this substrate 11 comprises a diapire 12 that is formed with a circuit layout 15 (not shown), and around these diapire 12 peripheries and a upwardly extending sidewall 13, and this diapire 12 matches with this sidewall 13 and defines the accommodation space 16 with an opening 14, and this circuit layout 15 is formed with plural pin 17 at this diapire 12 in the face of on the end face of this accommodation space 16.Step 31, be that the chip 2 that an inside has an oscillating circuit (not shown) is inserted this accommodation space 16 by this opening 14, and be formed with the contact 21 that plural number is connected with this oscillating circuit on the surface of this chip 2, and with this respectively this contact 21 electrically connect with respectively this corresponding pin 17 on this diapire 12, and in order to illustrate further, step 31 more comprises step following time:

(a1) contact 21 and these pins 17 electric connections of crystal method with these chips 2 covered in utilization.

(a2) insert colloid 3 at this chip 2 and 11 of this substrates.

Do not engage the method for (wire-bonding) herein with line, cover crystalline substance (flip-chip) method with pin 17 electric connections of the contact on the chip 2 21 and change to adopt with substrate 11, just on respectively this contact 21 on the chip 2, form a scolding tin (solder) or gold (Au) projection (bump) 22, and this projection 22 is connected on the contact 21 and corresponding pin 17 thereof of chip 2 with heat treatment mode again, and cover the electric signal transmission range that crystal method can reduce by 11 of chip 2 and substrates by this, increase the signal transmission speed, and can dwindle the size after chip 2 encapsulation, make that chip 2 encapsulation front and back sizes are very nearly the same, can reach the minimized requirement of volume.On the other hand, cover crystal method owing to adopt, thus only need insert colloid 3 at the contact 21 and 17 of the pins of chip 2, and need in accommodation space 16, not fill full colloid 3, just can strengthen integrally-built reliability, so can save manufacturing cost.In the present embodiment, this colloid 3 is one or its composition of aqueous epoxy base plate resin (epoxy) and the phenol (phenol) or the acid anhydride materials such as (anhydride) of low-viscosity, and the spherical silicon dioxide particle that has more plural small particle diameter in this colloid 3 is used as inserts.

Cooperate Fig. 6, step 32 is under a vacuum environment, to vibrate an end of a vibration son 4 by a conducting resinl (conductive adhesive) 5 and sub 4 to be connected on the sidewall 13 of this substrate 11, and make this vibration 4 to electrically connect with the oscillating circuit of these chip 2 inside, the end that this vibration 4 does not connect then can make this vibration 4 vibration up and down, and this vibration 4 is and the corresponding and vertical placement about in the of 2 of this chip, so compared to existing time-frequency elements, the design that nature can holding circuit and dwindle volume after being encapsulated; And owing to be to operate under vacuum environment, therefore vibration son 4 and chip 2 do not need encapsulation in advance, only need to place in this substrate 11 with the pattern of naked crystalline substance (bare chip), can avoid airborne humidity effect circuit, and save manufacturing cost.

Step 33 is imported a test signal to this chip 2, makes it drive this vibration 4 vibrations.

Cooperate Fig. 7, step 34 is to measure the frequency of oscillation of this vibration 4, and with a predetermined oscillation frequency mutually relatively after, deposit the exposed surface of plural particle 6 according to measurement result again to vibration 4, in the present embodiment, for purposes of illustration, be to be example with the physical vapor deposition (PVD) method, increase the quality of chip 22, whereby, because the plural particle 6 of deposition makes the quality of sub 4 surfaces of vibration slightly increase, frequency when fine setting reduces by 4 vibrations of vibration, certainly, the physical vaporous deposition that herein exemplifies can be evaporation, also can be sputter.And the material that this physical vaporous deposition adopted can be following material commonly used, comprising: gold, silver, chromium, aluminium, and the alloy of other equivalent substance or above-mentioned metal or with the compound of other material.And when frequency of oscillation meets expection, stop the step of deposition, obtain frequency of oscillation the most accurately thus.Certainly,, can't connect to the circuit of conducting to each other, so existing circuit does not have the doubt of short circuit on the vibration son 4 because the number of particles that increases is few.

On the other hand, if improve the frequency of oscillation of vibration 4, also can the synchronous measure frequency of oscillation in step 34 and adopt a dry-etching method (not shown), the existing particle of this exposed surface on etching off vibration 4 slightly, reduce the quality of vibration 4, and the frequency of oscillation of increase vibration 4, and when frequency of oscillation arrives this predetermined oscillation frequency, stop etching, because the particle that this kind etching method is removed is few, can the original interelement binding circuit of disjunction and destroy original circuit yet.And, make the frequency accuracy of this vibration 4 improve, and promote the yield of this time-frequency element 1 by the step that above-mentioned quality is finely tuned.

Cooperate Fig. 8, step 35 is under a vacuum environment, utilize a capping 18 these openings 14 of sealing, and be provided with the chip 2 behind crystal covered package in this substrate 11, and the sidewall 13 of substrate 11 is provided with vibration 4 after the quality fine setting, and this accommodation space 16 remained in a vacuum tight state, promptly make time-frequency elements 1.

Comprehensively above-mentioned, the manufacture method of time-frequency elements of the present invention is to utilize the crystal covered package method, and will vibrate son and chip be arranged in parallel up and down and dwindle the volume of time-frequency elements, owing to be in a vacuum environment, to operate, so can reduce the chance of the oxidized destruction of circuit, and before capping, more utilize a quality trim step accurately to control the frequency of oscillation of vibration son, make the present invention reach really that volume is little, yield is high, and the purpose of the accurate frequency of oscillation of tool.

Claims

1. A method of manufacturing a time-frequency element, wherein the time-frequency element has a substrate, the substrate includes a bottom wall forming a circuit layout, and a side wall surrounding the periphery of the bottom wall and extending upward, and the bottom wall Cooperating with the side wall to define an accommodating space with an opening, the circuit layout forms a plurality of pins on a top surface of the bottom wall facing the accommodating space, characterized in that the method includes the steps of:

(a) placing a chip with a plurality of contacts into the accommodating space through the opening, and electrically connecting each of the plurality of contacts of the chip with each of the corresponding pins on the bottom wall of the substrate by flip chip method;

(b) under a vacuum environment, one end of an oscillator corresponding to the chip and electrically connected is arranged on the side wall of the substrate;

(c) inputting a test signal to the chip to drive the vibrator to oscillate;

(d) measuring the oscillation frequency of the oscillator, and comparing it with a predetermined oscillation frequency, depositing/etching from an exposed surface of the oscillator exposed to the opening according to the measurement result, so as to fine-tune the quality of the oscillator;

(e) under the vacuum environment, sealing the above-mentioned opening of the substrate on which the vibrator and the chip are disposed with a cover, thereby keeping the accommodating space in a vacuum-tight state.

2. The method for manufacturing a time-frequency element according to claim 1, characterized in that: the step (e) is to deposit a plurality of particles on the exposed surface of the vibrator by using physical vapor deposition (PVD) to increase the oscillation The quality of the oscillator, thereby reducing the oscillation frequency of the oscillator.

3. The method for manufacturing time-frequency components according to claim 1, wherein the step (e) is to use dry etching to etch away the plurality of particles on the exposed surface to reduce the quality of the oscillator, by This increases the oscillation frequency of the oscillator.

4. The method for manufacturing time-frequency components according to claim 1, characterized in that: the step (a) further comprises the following steps:

(a1) Filling a colloid between the chip and the substrate.

5. A time-frequency element, characterized in that it comprises:

A substrate having a bottom wall and a side wall extending upward from a peripheral edge of the bottom wall, the bottom wall cooperates with the side wall to define an accommodating space with an opening, and the bottom wall forms a circuit layout , the circuit layout has a plurality of pins formed on a top surface of the bottom wall facing the accommodating space;

a cover, connected to an end of the side wall away from the bottom wall and closing the opening of the accommodating space, the accommodating space is in an airtight state of approximately vacuum or vacuum;

A chip is arranged in the accommodating space, the chip has an oscillating circuit, and a plurality of contacts corresponding to the pins, and each of the plurality of contacts of the chip is connected to each of the bottom wall of the substrate by a flip-chip method The corresponding pin is electrically connected;

an oscillator, arranged in the accommodating space corresponding to the top and bottom of the chip, and the oscillator is electrically connected to the oscillation circuit of the chip; and

A frequency fine-tuning particle layer is formed on the surface of the vibrator. The frequency fine-tuning particle layer includes a plurality of particles spaced apart from each other to increase the quality of the vibrator, thereby reducing the vibration frequency of the vibrator.

6. The time-frequency element according to claim 5, wherein the frequency fine-tuning particle layer material is one of the following metals: gold, silver, chromium and aluminum or a combination of two or more of the above metals.