A kind of silicon wafer single-sided polishing devices and methods thereforTechnical field
The present invention relates to polishing technical field, specifically a kind of silicon wafer single-sided polishing devices and methods therefor.
Background technique
Semi-conductor silicon chip is the main substrate material of modern super large-scale integration, generally passes through crystal pulling, slice, fallsThe integrated circuit level semiconductor silicon that the technical process such as angle, grinding (including being ground and grinding), burn into polishing, cleaning are fabricatedPiece.Wherein polishing process is very important process in rear road manufacturing procedure, and the precision of processing directly influences the several of productWhat parameter.
Existing polishing process is to combine to reach removal silicon chip surface by the rotation and ramming head rotation of polishing machine platform deep bidDamaging layer, it is ensured that silicon chip surface flatness requirement.Rotate polishing process usually can also jet polishing liquid, on the one hand utilize polishing fluidCooling down is carried out, the friction effect to silicon chip surface can be improved in the abrasive material contained in another aspect polishing fluid.But it is rotating throughCheng Zhong is ground the waste material to get off and is not easy to be discharged between rubbing head and silicon wafer, and waste material clast is since granularity is larger, to silicon waferThe flatness of polishing has an adverse effect.
Summary of the invention
The purpose of the present invention is to provide a kind of silicon wafer single-sided polishing devices and methods therefors, to solve in above-mentioned background techniqueThe problem of proposition.
To achieve the above object, the invention provides the following technical scheme:
A kind of silicon wafer single-sided polishing device, comprising: upper clamping disk, inner sleeve, lower clamping disk, polishing disk, vibrating motor andPlate-like elastic part, the upper clamping disk are fixed on lower clamping disk, and the polishing disk upper end is located at upper clamping disk and lower clamping diskBetween, the vibrating motor is mounted on polishing disk top surface, and the vibrating motor can produce the exciting force along polishing disk radial direction；The end of the plate-like elastic part is fixed in the cavity between inner sleeve and lower clamping disk, the plate-like elastic part it is anotherEnd is bonded with the side of polishing disk, and multiple groups are arranged in the plate-like elastic part, and arrange along the circumference array of polishing disk；The polishingThe groove of several annular shapes is arranged in the face of trying to get to the heart of a matter, and the groove is connected by radial slot, and radial slot is arranged radially along polishing disk,And it is connected to the lateral edge of polishing disk.
As a further solution of the present invention: connection frame, the connection frame top are fixedly connected on the upper clamping diskIt is movably arranged on stroke beam.
As a further solution of the present invention: the plate-like elastic part uses spring steel material.
As a further solution of the present invention: what the lower clamping disk was contacted with polishing disk is arranged what circumferentially array was arrangedMultiple balls.
A kind of silicon wafer single-sided polishing method of silicon wafer single-sided polishing device, comprising the following steps:
1), silicon wafer is fixed on fixture, so that silicon wafer is attached to polishing disk bottom surface fixture promotion, and according to polishing intensity controlPressing force between silicon wafer and polishing disk processed；
2), starting vibrating motor is polished, and at the uniform velocity moves polishing disk along stroke beam, and at the uniform velocity movement speed is 3-5m/S, vibrating motor revolving speed are 960-1500r/min；
3) after, polishing disk is moved to silicon wafer end, polishing disk, movement speed 2-3m/s, by vibrating motor are moved backwardRevolving speed is increased to 3000r/min or more.
As a further solution of the present invention: during step 2 and step 3, polishing fluid spray head is set by polishing disk,Polishing fluid spray head is tilted towards silicon chip surface jet polishing liquid.
As a further solution of the present invention: the polishing fluid includes at least the raw material of following parts by weight: the four of 12-15%Boratex, the activating agent of 3-6%, the sorbic alcohol of 1-2%, the hydrofluoric acid of 0.5-0.8%, abrasive material and surplus water.
As a further solution of the present invention: the activating agent is OP-10 emulsifier.
As a further solution of the present invention: the abrasive material is silicon carbide or silica.
As a further solution of the present invention: the abrasive grain partial size of polishing fluid is 0.1-5um in step 2；It is thrown in step 3The abrasive grain partial size of light liquid is 0.02-2um.
Compared with prior art, the beneficial effects of the present invention are: silicon wafer single-sided polishing device of the invention, passes through vibration electricityThe effect of machine and elastic component generates the revolution motion around the center of circle, carries out polishing grinding to silicon wafer, keeps silicon chip surface flatness higher；Silicon wafer single-sided polishing method, carries out a rough polishing and fine polishing respectively with low frequency and high-frequency, and finishing polish is used for rough polishingThe silicon face of light carries out finishing reparation, reaches higher polishing effect.
Detailed description of the invention
Fig. 1 is the structural diagram of the present invention.
Fig. 2 be in Fig. 1 A to schematic cross-sectional view.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, completeSite preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based onEmbodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every otherEmbodiment shall fall within the protection scope of the present invention.
Please refer to Fig. 1~2, in the embodiment of the present invention, a kind of silicon wafer single-sided polishing device, comprising: upper clamping disk 3, inner sleeveCylinder 4, lower clamping disk 5, polishing disk 6, vibrating motor 9 and plate-like elastic part 10, the upper clamping disk 3 are fixed on lower clamping disk 5,Between upper clamping disk 3 and lower clamping disk 5, the vibrating motor 9 is mounted on 6 top surface of polishing disk for 6 upper end of polishing disk, vibrationDynamic motor 9 can produce the exciting force along 6 radial direction of polishing disk, make the radially random motion in the horizontal plane of polishing disk 6；InstituteState in the cavity that the end of plate-like elastic part 10 is fixed between inner sleeve 4 and lower clamping disk 5, plate-like elastic part 10 it is anotherEnd be bonded with the side of polishing disk 6, and multiple groups are arranged in plate-like elastic part 10, and along the circumference array of polishing disk 6 arrangement, general when polishingSilicon wafer 7 is fixed on fixture 8, and mobile fixture 8 makes two using certain precompression to silicon wafer 7 is contacted with 6 bottom of polishing diskPerson is in close contact, and starting vibrating motor 9 makes the micromotion of the generation of polishing disk 6 radially, and in the effect of each plate-like elastic part 10Under so that polishing disk 6 is generated revolution centered on its center of circle, polishing grinding is carried out to 7 surface of silicon wafer.
Connection frame 2 is fixedly connected on the upper clamping disk 3,2 top of connection frame is movably arranged on stroke beam 1,It can move linearly along stroke beam 1.
The groove 61 of several annular shapes is arranged in 6 bottom surface of polishing disk, and the groove 61 is connected to by radial slot 62The lateral edge of polishing disk 6, radial slot 62 are arranged radially along polishing disk 6, and during the polishing process, polishing fluid is mingled with grinding and producesRaw clast enters in groove 61, and is arranged by radial slot 62 from the edge of polishing disk 6 under the centrifugal force effect that rotation generatesOut.
The plate-like elastic part 10 uses spring steel material, has elasticity and fatigue durability well.
Setting multiple balls 11 that circumferentially array is arranged that the lower clamping disk 5 is contacted with polishing disk 6, to reduce polishingThe friction when vibration of disk 6 with lower clamping disk 6.
A kind of polishing method of silicon wafer single-sided polishing device, comprising the following steps:
1), silicon wafer 7 is fixed on fixture 8, so that silicon wafer 7 is attached to 6 bottom surface of polishing disk the promotion of fixture 8, and according to polishingPressing force between strength control silicon wafer 7 and polishing disk 6；
2), starting vibrating motor 9 is polished, and at the uniform velocity moves polishing disk 6 along stroke beam 1, and at the uniform velocity movement speed is 3-5m/s, 9 revolving speed of vibrating motor are 960-1500r/min, this is rough polishing；
3) after, polishing disk 6 is moved to 7 end of silicon wafer, polishing disk 6, movement speed 2-3m/s, by vibration electricity are moved backward9 revolving speed of machine is increased to 3000r/min or more, and for this step as the finishing polish to silicon wafer 7, motor speed is high, and vibration frequency is high, usesIt is modified in the surface of out-of-flatness.
During step 2 and step 3, polishing fluid spray head is set by polishing disk 6, polishing fluid spray head is tilted towards silicon wafer 7Surface jet polishing liquid, the polishing fluid are at least made of the raw material of following weight ratio: sodium tetraborate, the 3-6% of 12-15%Activating agent, the sorbic alcohol of 1-2%, the hydrofluoric acid of 0.5-0.8%, abrasive material and surplus water, the activating agent be OP-10 emulsificationAgent, the abrasive material are silicon carbide or silica, and abrasive grain partial size is 0.1-5um (using in step 2) or 0.02-2um (stepIt is used in 3).
It is obvious to a person skilled in the art that invention is not limited to the details of the above exemplary embodiments, Er QieIn the case where without departing substantially from spirit or essential attributes of the invention, the present invention can be realized in other specific forms.Therefore, no matterFrom the point of view of which point, the present embodiments are to be considered as illustrative and not restrictive, and the scope of the present invention is by appended powerBenefit requires rather than above description limits, it is intended that all by what is fallen within the meaning and scope of the equivalent elements of the claimsVariation is included within the present invention.Any reference signs in the claims should not be construed as limiting the involved claims.
In addition, it should be understood that although this specification is described in terms of embodiments, but not each embodiment is only wrappedContaining an independent technical solution, this description of the specification is merely for the sake of clarity, and those skilled in the art shouldIt considers the specification as a whole, the technical solutions in the various embodiments may also be suitably combined, forms those skilled in the artThe other embodiments being understood that.