CN105690239A

CN105690239A - Grinding method for LiNbO3 integrated optical device chip

Info

Publication number: CN105690239A
Application number: CN201410682508.4A
Authority: CN
Inventors: 李俊伟; 王腾飞; 杨成武
Original assignee: Shanghai Hengtong Photoelectric Technology Co Ltd
Current assignee: Shanghai Aoshi Control Technology Co Ltd
Priority date: 2014-11-24
Filing date: 2014-11-24
Publication date: 2016-06-22
Anticipated expiration: 2034-11-24
Also published as: CN105690239B

Abstract

The invention relates to a grinding method for a LiNbO3 integrated optical device chip. The method includes the following steps: (1) processing a chip: performing cutting-up forming on a chip to be grinded, and cleaning and drying the chip to be grinded; (2) bonding an accompany piece on the chip: coating an end surface of the processed chip with glue, and then bonding the accompany piece on the processed chip, performing tabletting and solidifying on the processed chip with the accompany piece; (3) assembling the chip: cleaning the end surface and the surface of the bonded chip, arranging the bonded chip on a grinding clamp for grinding; and (4) grinding the chip: firstly, performing coarse grinding, secondly, performing fine grinding, and finally, performing polishing treatment, and then checking the grinding quality of the chip. Compared with the prior art, the method is more accurate in grinding removal amount, can ensure flat end surface of a working face and can avoid turned-down edges, and in this way, the chip loss can be further reduced, and the return loss of the device can be reduced.

Description

LiNbO3Integrated optical device chip Ginding process

Technical field

The present invention relates to a kind of chip Ginding process, especially relate to a kind of LiNbO₃Integrated optical device chip Ginding process。

Background technology

LiNbO₃Crystal has very big linear electro-optic coefficient, has bigger transmitance, and crystal growth technique is ripe within the scope of the optical wavelength of 400nm～4500nm, and low price, is the optimum selection of integrated optics multifunction chip。This devices use electrooptic effect of lithium columbate crystal, there is the advantages such as response fast (the electro-optic response time is 10-15s magnitude), electromagnetism interference, and make use of its maximum linear electro-optic coefficient r33 (=30.8pm/V), therefore introduce LiNbO₃Integrated optics multifunction chip is a quantum leap of fiber-optics gyroscope development。

In the making of integrated optical fiber gyro multifunction chip, it is necessary to will make the LiNbO of intact fiber waveguide, electrode₃Chip is accurately directed at optical fiber and is bonded together, because only that LiNbO₃After chip is accurately connected with optical fiber, relies on optical fiber could conveniently complete input and the output of optical signal, also could realize the modulation function to optical signal。

Current technique is LiNbO₃LiNbO is guaranteed with optical fiber when chip couples₃Tangential and the waveguide wafer of chip tangentially identical。Finally optical fiber is coupled with waveguide, adopt UV photo-curing epoxy resin binding agent to fix, LiNbO₃Chemical adhesive bonding strength between crystal and optical fiber is equivalent to be mechanically connected。Ensure optical fiber and LiNbO₃The coupling loss of chip waveguide is minimum, and reduces return loss。And at LiNbO₃During the grinding of chip, being very coarse through the substrate two ends of cutting, hackly end face will cause scattering of light, make the coupling efficiency of waveguide two ends and optical fiber be substantially reduced。It is thus desirable to directly two end faces of chip waveguide are ground polishing, the end face of grinding and polishing must have certain angular relationship with waveguide, simultaneously because diffused waveguide formed after against wafer surface, easily cause burnishing surface to intersect with wafer work surface and fillet, turned-down edge occur, collapse limit etc., affect the coupling loss of waveguide, also increase the return loss of device。

Summary of the invention

Defect that the purpose of the present invention is contemplated to overcome above-mentioned prior art to exist and a kind of LiNbO is provided₃Integrated optical device chip Ginding process, the method is to accompany sheet to be ground at work surface by end face is bonding, it is ensured that whole work burnishing surface intersects with wafer work surface and do not have fillet, turned-down edge, collapses the phenomenons such as limit。

The purpose of the present invention can be achieved through the following technical solutions:

A kind of LiNbO₃Integrated optical device chip Ginding process, the method comprises the following steps:

(1) chip manufacture: chip cutting-up to be ground is shaped, clean and toasts dry；

(2) chip bonding die: after the die terminals topcoating glue after processed, bonding accompanies sheet, and to its tabletting and solidification；

(3) chip assembling: be cleaned processing to its end face and surface by bonding chip, be contained on grinding clamp, prepares to grind；

(4) chip grinds: first roughly grinds, then fine grinding, is finally polishing, and checks its Grinding Quality。

In step (2), bonding is realized by die bonding device,

Described chip adhering device includes a base, it is arranged on the standing screw on base and movable block and the alignment pin being arranged on base, through hole slot is offered in the middle of described movable block, described standing screw is arranged in through hole slot, when standing screw releasing orientation, described movable block can move forward and backward around standing screw or rotate, when standing screw is tightened, movable block is fixed, perpendicular is offered on the top of described movable block, the top of two movable blocks moves together docking in order to clamp chip, chip after clamping bonds after end face gluing and accompanies sheet。

In step (2), described tableting processes is realized by chip preforming device,

Described chip preforming device includes being fixed with on a base plate, base plate perpendicular support, perpendicular support is connected to lateral frame, threaded on lateral frame have tabletting screw rod, and the lower end of this tabletting screw rod is connected to afterburning block, and the tabletting screw rod outer cover between afterburning block and lateral frame is provided with adjustable spring；During tabletting, the chip after bonding is accompanied sheet is placed between base plate and afterburning block, and keeps chip and the connecting sewing accompanying sheet to be positioned at below afterburning block, by rotary tablet compression screw rod, chip is applied active force vertically downward。

In step (2), before tabletting, processing accompanying sheet and chip to be heated, it affects its bonding plane effect and adhesive strength。

In step (1), chip cutting-up to be ground become parallelogram block。

In step (4), by under the effect of abrasive on grinder, gravity coordinates rotation to do period mechanical grinding。

In step (4), process of lapping controls certain grinding removal amount。

Compared with prior art, use the present invention method be ground, grind removal amount more accurate, it is ensured that work surface end face smooth, without turned-down edge etc., thus reducing the loss of chip further, also reduce the return loss of device。

Accompanying drawing explanation

Fig. 1 is the process flow diagram of the present invention；

Fig. 2 is die bonding apparatus structure schematic diagram；

Fig. 3 is chip preforming device structural representation；

Fig. 4 is the chip end view drawing after chip grinds。

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail。

Embodiment

A kind of LiNbO₃Integrated optical device chip Ginding process, technological process is as it is shown in figure 1, the method comprises the following steps:

(1) chip manufacture: chip cutting-up to be ground becomes parallelogram block, length and width 52 × 22, acute angle 80 °, clean up and toast dry, allow its surface aqueous vapor evaporate；

(2) chip bonding die: after the die terminals topcoating glue after processed, bonding accompanies sheet, and to its tabletting and solidification, need to requiring that whole process gluing is uniformly and pollution-free, before tabletting, processing accompanying sheet and chip to be heated, it affects its bonding plane effect and adhesive strength；

(4) chip grinds, and by under the effect of abrasive on grinder, gravity coordinates rotation to do period mechanical grinding: first roughly grinds, then fine grinding, is finally polishing, controls certain grinding removal amount, and check its Grinding Quality in process of lapping。

In step (2), bonding is realized by die bonding device, chip adhering device is as shown in Figure 2, including a base 7, it is arranged on the standing screw 10 on base 7 and movable block 8 and the alignment pin 9 being arranged on base 7, alignment pin 9 realizes the location of chip bonding die, through hole slot is offered in the middle of movable block 8, standing screw 10 is arranged in through hole slot, when standing screw 10 releasing orientation, movable block 8 can move forward and backward around standing screw 10 or rotate, when standing screw 10 is tightened, movable block 8 is fixed, perpendicular is offered on the top of movable block 8, the top of two movable blocks 8 moves together docking in order to clamp chip, chip after clamping bonds after end face gluing and accompanies sheet。

In step (2), tableting processes is realized by chip preforming device, chip preforming device is as shown in Figure 3, including a base plate 1, base plate 1 are fixed with perpendicular support 2, perpendicular support 2 is connected to lateral frame 3, threaded on lateral frame 3 have tabletting screw rod 4, and the lower end of this tabletting screw rod 4 is connected to afterburning block 6, and tabletting screw rod 4 outer cover between afterburning block 6 and lateral frame 3 is provided with adjustable spring 5；During tabletting, the chip after bonding is accompanied sheet is placed between base plate 1 and afterburning block 6, and keeps chip and the connecting sewing accompanying sheet to be positioned at below afterburning block 6, by rotary tablet compression screw rod 4, chip is applied active force vertically downward。

Chip grind after chip end view drawing as shown in Figure 4, chip 12 with accompany sheet 13 end face smooth, without turned-down edge, its abradant surface 13 smooth surface。

The above-mentioned description to embodiment is to be understood that for ease of those skilled in the art and use invention。These embodiments obviously easily can be made various amendment by person skilled in the art, and General Principle described herein is applied in other embodiments without through performing creative labour。Therefore, the invention is not restricted to above-described embodiment, those skilled in the art's announcement according to the present invention, the improvement made without departing from scope and amendment all should within protection scope of the present invention。

Claims

1. a LiNbO₃Integrated optical device chip Ginding process, it is characterised in that the method comprises the following steps:

2. a kind of LiNbO according to claim 1₃Integrated optical device chip Ginding process, it is characterised in that in step (2), bonding is realized by die bonding device,

3. a kind of LiNbO according to claim 1₃Integrated optical device chip Ginding process, it is characterised in that in step (2), described tableting processes is realized by chip preforming device,

4. a kind of LiNbO according to claim 1₃Integrated optical device chip Ginding process, it is characterised in that in step (2), before tabletting, processes accompanying sheet and chip to be heated。

5. a kind of LiNbO according to claim 1₃Integrated optical device chip Ginding process, it is characterised in that in step (1), becomes parallelogram block by chip cutting-up to be ground。

6. a kind of LiNbO according to claim 1₃Integrated optical device chip Ginding process, it is characterised in that in step (4), by under the effect of abrasive on grinder, gravity coordinates rotation to do period mechanical grinding。

7. a kind of LiNbO according to claim 1₃Integrated optical device chip Ginding process, it is characterised in that in step (4), controls certain grinding removal amount in process of lapping。