CN2819647Y

CN2819647Y - Ceramic sealer of crystal oscillator

Info

Publication number: CN2819647Y
Application number: CN 200520115009
Authority: CN
Inventors: 吴崇隽; 吴柱梅; 党桂彬; 黎柏其
Original assignee: YUEKE QINGHUA ELECTRONIC CERAMIC CO Ltd ZHUHAI
Current assignee: Zhuhai Yueke Jinghua Electronic Ceramics Co., Ltd.
Priority date: 2005-08-02
Filing date: 2005-08-02
Publication date: 2006-09-20
Anticipated expiration: 2015-08-02

Abstract

The utility model relates to a ceramic packaging element for crystal oscillators. Compared with the traditional packaging structure, the ceramic packaging structure obtains improvement to optimize a manufacturing technique. The ceramic packaging element for crystal oscillators makes use of a paster type ' upside-down 'method to the common ' positive installation 'ceramic packaging, and is distinguished from the traditional ceramic packaging element with a pin. Metallized wire laying is carried out on a bottom laminate. The bottom laminate is provided with an internal terminal and an external terminal which are electrically connected. A wafer is glued on the internal terminal of the bottom laminate by conductive adhesive. The bottom laminate is used as a basal body of the load bearing wafer to realize the input and the output of a signal. Simultaneously, a packaging cover is a hollow cavity, can be a ceramic cover and a metal cover (such as a kovar alloy cover), and provides an effective oscillating space for crystals. When the ceramic packaging element for crystal oscillators is packaged, the packaging cover is reversely covered on the bottom laminate. Through welding and sealing, the utility model forms a necessary sealing cavity for effective crystal oscillation.

Description

A kind of ceramic package of crystal oscillator

Technical field

The utility model relates to the ceramic package that is equipped with as a kind of crystal oscillator of frequency generator and frequency regulator.

Background technology

Because the continuous development of mobile phone, static digital camera, PC mainboard, notebook computer and video-game, double-digit growth can appear in the demand expectation of crystal oscillator.But because the lamination of traditional ceramics pedestal is total to burning technology and complicated design, as Fig. 1, make that the production cost of base of ceramic is high always, and output also is subjected to the restriction of technology, equipment each side, can not be satisfied with the growing market demand far away, therefore seek a kind of simple method and replace present design, manufacture method extremely urgent, the utility model arises at the historic moment under this market demand.

The utility model content:

The purpose of this utility model provides a kind of ceramic package of crystal oscillator, and its meaning is to enhance productivity, reduce production costs, and satisfies the growing market demand biglyyer.

Above-mentioned purpose of the present utility model adopts following technical scheme to be achieved:

The ceramic package of crystal oscillator is characterized in that: comprising:

The bottom plate has internal terminal and outside terminal, and internal terminal is electrically connected to outside terminal,

Lid is located immediately on the bottom plate with " upside-down mounting " form, and described lid is pottery or metal alloy, and inside is the cavity that plays sealing and hold the wafer double action.

According to the utility model, inside and outside terminal of bottom plate and be electrically connected material is the W that burns altogether, or the Ag or the Ag/Pd that adopt thick film technology to form.

According to the utility model, internal terminal is formed on the bottom plate with the Ag of 40 μ m-50 μ m print thickness or the form of Ag/Pd, and Gold plated Layer is arranged at its top.

According to the utility model, the metallization wiring is arranged on the bottom plate, the bottom plate has the electrical connection between internal terminal and outside terminal and the interior external terminal, wafer is bonded on the internal terminal of bottom plate by conducting resinl, the bottom plate is as a bearing wafer and realize the matrix of the input and the output of signal.

According to the utility model, the internal terminal on the bottom plate has makes wafer and bottom plate keep the height of certain space length, and this spatial altitude can directly print thicker conductive layer, is perhaps supported and is formed by other metal or nonmetallic pad.

According to the utility model, electrically connect as that other via connects or be the inner via hole connection on the bottom plate.

According to the utility model, ceramic cap is made of two-layer, around be coated with one the circle low-melting-point glass.

According to the utility model, ceramic cap is made of two-layer, is sintering lamination in air atmosphere, around be coated with low-melting-point glass.

According to the utility model, crown cap is by one time punching molded lid, is packaged as a whole with metallized in advance bottom plate all around.

Be printed with the metal circular layer around the upper surface of bottom plate, and the becket laminar surface has Gold plated Layer, becket is welded on the bottom plate.

The manufacture method of the ceramic package of the utility model crystal oscillator, the bottom plate that it is characterized in that having inside and outside terminal and electrical connection thereof is an individual layer, can adopt non-method of burning metal altogether such as thick film to realize the metallization of pottery.So just solved the problem of the easy oxidation of common burning metal, the reproducibility of common burning porcelain sintering and this big contradiction of oxidizability of binder removal have been solved, the investment of production equipment aspect has also significantly reduced, and binder removal and sintering can carry out simultaneously, has not had the expensive problem of reducing atmosphere stove.

On the other hand, based on the consideration of its electric property.In general, at high frequency, high performance electronic package assembling, the parallel path that is positioned at many vias of multilager base plate will amplify leakage current.Ideally, via count is few more, just can reduce parasitic capacitance and the total leakage current do not expected more.The utility model directly designs the internal terminal with certain altitude on the bottom plate, removed the buffering thin slice on the base of ceramic traditional design, also just lack the via that cushions on the thin slice, thereby avoiding the problem of parallel electrically conductive path electric leakage, strengthening the functional reliability of high-frequency signal net.

The third aspect, " hat type " design of lid make it form the useful space of wafer vibration in the sealing of bottom plate.Owing to do not need metallization, can adopt the lamination sintering method of conventional ceramic, sintering in air atmosphere can improve the air-tightness of encapsulation and the outward appearance fineness of pottery effectively.In addition, low-melting seal glass is adopted in the periphery of lid, guarantees the height uniformity when fusing, for the air-tightness that encapsulates has improved assurance.

Description of drawings

Fig. 1 is traditional SMD multi-layer ceramics enclosure base structural representation

The SMD base of ceramic structural representation of crown cap, inner via hole that Fig. 2 the utility model adopts

The SMD base of ceramic structural representation of ceramic cap, inner via hole that Fig. 3 the utility model adopts

The SMD base of ceramic structural representation of the crown cap that Fig. 4 the utility model adopts, inner via hole and band support slice

The SMD base of ceramic structural representation of the ceramic cap that Fig. 5 the utility model adopts, inner via hole and band support slice

The SMD base of ceramic structural representation of ceramic cap, other via that Fig. 6 the utility model adopts

The SMD base of ceramic ceramic cover plate of Fig. 7 structural representation

Fig. 8, the SMD base of ceramic bottom of Fig. 9 inner via hole plate front metal wiring schematic diagram

The SMD base of ceramic bottom of the other via of Figure 10 plate front metal wiring schematic diagram

The SMD base of ceramic bottom of Figure 11 plate reverse side metal line schematic diagram

Embodiment:

Describe preferred embodiment of the present utility model in detail below in conjunction with accompanying drawing.Fig. 1 shows traditional SMD ceramic packaging structure, and 11 is bottom, 12 and 12` be the buffering thin slice, 13 and 13` for cover support slice, 14 and 14` be that kovar encircles, 15 is top cover, 16 is wafer.

Fig. 2, Fig. 3, Fig. 4, Fig. 5 and Fig. 6 show four kinds of forms that the utility model is used for the ceramic package pedestal of crystal oscillator.21 is the bottom plate among Fig. 2, and 22 is crown cap, and 23 is wafer, 24 and 24` be internal terminal, 25 and 25` be outside terminal, 26 and 26` be via, 27 and 27` be conducting resinl, 28 and 28` be the weld metal layers of crown cap and bottom plate.31 is the bottom plate among Fig. 3,32 and 32` be ceramic cap, 33 is wafer, 34 and 34` be internal terminal, 35 and 35` be outside terminal, 36 and 36` be via, 37 and 37` be conducting resinl, 38 and 38` be seal glass.41 is the bottom plate among Fig. 4, and 42 is crown cap, and 43 is wafer, 44 and 44` be internal terminal, 45 and 45` be outside terminal, 46 and 46` be via, 47 and 47` be conducting resinl, 48 and 48` be the weld layer of crown cap and bottom plate, 49 and 49` be metal or nonmetal support slice.51 is the bottom plate among Fig. 5,52 and 52` be ceramic cap, 53 is wafer, 54 and 54` be internal terminal, 55 and 55` be outside terminal, 56 and 56` be via, 57 and 57` be conducting resinl, 58 and 58` be seal glass, 59 and 59` be metal or nonmetal support slice.61 is the bottom plate among Fig. 6,62 and 62` be ceramic cap, 63 is wafer, 64 and 64` be internal terminal, 65 and 65` be outside terminal, 66 and 66` be via, 67 and 67` be conducting resinl, 68 and 68` be seal glass.

Crystal oscillator ceramic packaging of the present utility model provides a kind of structure, and with respect to prior art, it not only can simplify common burning production technology, and can reduce the quantity of the ceramic sheet that piles up, thereby has reduced the thickness of whole encapsulation.For this purpose, the utility model provides five kinds of different structures, and it has simplified ceramet of the prior art burning technology altogether, has removed buffering thin slice and lid support slice.To further describe this structure of the present utility model below.

With reference to Fig. 2, ceramic packaging of the present utility model comprises bottom plate 21, is positioned at nethermost part, this bottom plate 21 is forms of ceramic substrate, and side and downside have internal terminal 24 thereon, 24` and

outside terminal

25,25`,

internal terminal

24,24` is to be electrically connected 26, and 26` is to outside

terminal

25,25`, and

internal terminal

24,24` is formed on the bottom plate 21 with the Ag of about 50 μ m print thickness or the form of Ag/Pd, and its top is gold-plated again.Internal terminal 24, the thickness of 24` must be guaranteed, just can make 23 effectively vibrations of wafer.

The height of internal terminal can realize that also as Fig. 4 and Fig. 5, the requirement of printing like this about thickness 50 μ m just can correspondingly reduce by support slice, and this support slice can be by metal or nonmetal making.

Inside and outside terminal is to adopt the non-technology print that burns altogether on bottom plate 21, owing to non-burning altogether can not considered the inconsistent problem that causes bottom slab warping distortion of the pottery and the percent of firing shrinkage of metal paste, so, when sintering, can ignore pottery and generally the flexural deformation of the crystal oscillator ceramic packaging that cause inconsistent with thermal expansion metal coefficient (CET) as long as print thickness is guaranteed.

Owing to do not design pottery buffering thin slice in addition; bottom plate 21 must have the thickness of about 0.6mm, and this highly enough wafer 23 carries out stable vibration and make bottom plate 21 absorb the external impact that is applied on the wafer 23 to a certain extent protecting wafer 23.

Correspondingly, the bottom plate can carry out two kinds of circuit design, and as Fig. 8, Fig. 9 and shown in Figure 10, promptly the via of inside and outside terminal can be designed as inner via hole, and package structure such as Fig. 2, Fig. 3, Fig. 4 and Fig. 5 also can be designed as other via, as Fig. 6.When being designed to inner via hole, require to control better the percent of firing shrinkage of grout metal, in order to avoid the shrinkage of metal and substrate differs too big and cracking or come off the air-tightness of assurance packaging part when burning till.

Lid of the present utility model is " hat type " design, and the height of the about 0.3mm of " shade " design makes caping and bottom plate that certain clearance be arranged, and guarantees that wafer can effectively vibrate.

Lid can be the one time punching molded metal alloy that comes out, and as Fig. 2 and Fig. 4, also can be pottery, as Fig. 3, Fig. 5 and Fig. 6.

Ceramic cap is two-layer design, as Fig. 7, does not have the metallization wiring, can carry out sintering in air atmosphere behind the lamination, has avoided the problem of the easy oxidation of common burning metal.

The seal glass of the about 0.2mm thickness of " shade " coating one circle of ceramic cap, sealing-in only need be heated to the softening temperature of glass and just can finish, and utilize the surface tension of melten glass, glass in height can be consistent automatically, so both guarantee the evenness of ceramic packaging, guaranteed the air-tightness of encapsulation again.

Material selection metal alloy as operculum, then the bottom plate will be changed when design accordingly, promptly around the upper surface of bottom plate, to print a becket, as Fig. 8, and require the becket surface gold-plating, could guarantee that like this becket can be welded on the bottom plate well, realize the good air-tightness sealing-in.

As mentioned above, the utility model has been simplified the production technology of ceramic packaging, has reduced the requirement of production equipment, is more suitable in requirements of mass production.

The utility model has also minimized ceramic packaging, reduce the buffering thin slice of close bottom plate, and realized four kinds of practical designs, enriched the design form of SMD ceramic packaging, satisfy the needs of different function different frequencies better, and reduced production cost.

Claims

1, a kind of ceramic package of crystal oscillator is characterized in that: comprising:

The bottom plate have internal terminal and outside terminal, and internal terminal is electrically connected to outside terminal, lid, be located immediately on the bottom plate with " upside-down mounting " form, described lid is pottery or metal or Kovar alloy, and inside is the cavity that plays sealing and hold the wafer double action.

2, the ceramic package of a kind of crystal oscillator according to claim 1 is characterized in that: inside and outside terminal of bottom plate and be electrically connected material is the W that burns altogether, or the Ag or the Ag/Pd that adopt thick film technology to form.

3, the ceramic package of a kind of crystal oscillator according to claim 1 is characterized in that: internal terminal is formed on the bottom plate with the Ag of 40 μ m-50 μ m print thickness or the form of Ag/Pd, and Gold plated Layer is arranged at its top.

4, the ceramic package of a kind of crystal oscillator according to claim 1, it is characterized in that: the metallization wiring is arranged on the bottom plate, the bottom plate has the electrical connection between internal terminal and outside terminal and the interior external terminal, wafer is bonded on the internal terminal of bottom plate by conducting resinl, the bottom plate is as a bearing wafer and realize the matrix of the input and the output of signal.

5, according to the ceramic package of claim 1 or 2 or 3 or 4 described a kind of crystal oscillators, it is characterized in that: the internal terminal on the bottom plate has makes wafer and bottom plate keep the height of certain space length, this highly directly type metal slurry formation is perhaps formed by other metal or nonmetallic support slice.

6, the ceramic package of a kind of crystal oscillator according to claim 5 is characterized in that: electrically connect as that other via connects or be the inner via hole connection on the bottom plate.

7, the ceramic package of a kind of crystal oscillator according to claim 6 is characterized in that: ceramic cap is made of two-layer, is sintering lamination in air atmosphere, around be coated with low-melting-point glass.

8, the ceramic package of a kind of crystal oscillator according to claim 7 is characterized in that: crown cap is for by one time punching molded lid, is packaged as a whole with metallized in advance bottom plate all around.

9, the ceramic package of a kind of crystal oscillator according to claim 8 is characterized in that: be printed with the metal circular layer around the upper surface of bottom plate, and the becket laminar surface has Gold plated Layer, becket is welded on the bottom plate.