Ultrasonic scroll saw cutting process for non-conductive hard fragile material
Technical field
The present invention relates to the cutting method of non-conductive hard brittle material, belong to the cutting technique field of non-conductive hard brittle material.
Background technology
Valuable non-conductive hard brittle materials such as monocrystalline silicon, polysilicon, quartz crystal, SiC monocrystalline, sapphire crystal are widely used in integrated circuit (IC), solar cell and optoelectronic areas.Along with the continuous development of modern technologies, above-mentioned crystalline size constantly increases, and wafer thickness is tending towards thin typeization.Reducing of the increase of crystalline size and wafer thickness brought new challenge for the cutting processing technology of crystal cut.
At present silk section of free abrasive saw and concretion abrasive saw silk microtomies of adopting are carried out the cutting of crystal cut more, the multi-thread saw of free abrasive silk microtomy particularly, it is the main method of large size single crystal silicon section during present IC makes, its basic principle as shown in Figure 1, workbench up, crystal bar 4 is fixed on the workbench by anchor clamps 5, saw silk 1 is wrapped on the capstan roll 2, by spraying lapping liquid in the nozzle 3, saw silk 1 moves cutting crystal bar 4 under the drive of driving mechanism, once can cut the multi-disc crystal.The subject matter that this method exists is that cutting efficiency is low, the crystalline material higher to hardness, as SiC monocrystalline, sapphire crystal etc., even the wear rate that the saw silk occurs is higher than the clearance that is cut material, can not give full play to the performance of the super hard abrasives such as diamond on the saw silk.
Summary of the invention
The invention reside in the deficiency that overcomes existing non-conductive hard brittle material cutting technique, provide a kind of cutting efficiency high ultrasonic scroll saw cutting process for non-conductive hard fragile material.
Ultrasonic scroll saw cutting process for non-conductive hard fragile material of the present invention is:
Non-conductive hard fragile material is by the cutting of saw silk, and the saw silk carries out unidirectional or moves back and forth, and realizes main cutting movement, and the saw silk is realized feed motion along moving perpendicular to the direction of its main cutting movement simultaneously; On the other hand, the additional direction of vibration that has ultrasonic vibration, this ultrasonic vibration to make non-conductive hard brittle material is consistent with a direction of sawing main cutting movement direction of silk and direction of feed at least on non-conductive hard brittle material.
The present invention carries out the compound cuts processing of non-conductive hard brittle material by ultrasonic vibration and saw silk cutting movement, the saw silk cut it when non-conductive hard brittle material vibrated, cutting efficiency is higher by 30~50% than simple saw silk section cutting, and improved cutting accuracy, be a kind of cutting technique of high-efficiency and precision.
Description of drawings
Fig. 1 is the incision principle schematic diagram that existing non-conductive hard brittle material adopts the multi-thread microtomy of free abrasive.
Fig. 2 is the incision principle schematic diagram of ultrasonic scroll saw cutting process for non-conductive hard fragile material of the present invention.
Among the figure: 1, saw silk, 2, capstan roll, 3, nozzle, 4, crystal bar, 5, anchor clamps, 6, guide wheel, 7, workbench.
The specific embodiment
Below in conjunction with drawings and Examples method of the present invention is described further.
The basic functional principle of the multi-thread microtomy of existing free abrasive saw silk as shown in Figure 1, workbench (not drawing among the figure) up, crystal bar 4 is fixed on the workbench by anchor clamps 5, saw silk 1 is wrapped on the capstan roll 2, by spraying lapping liquid in the nozzle 3, saw silk 1 moves cutting crystal bar 4 under the drive of driving mechanism, once can cut the multi-disc crystal.This method cutting efficiency is low, the crystalline material higher to hardness, and as SiC monocrystalline, sapphire crystal etc., even the wear rate of appearance saw silk is higher than the clearance that is cut material.
The incision principle of ultrasonic scroll saw cutting process for non-conductive hard fragile material of the present invention as shown in Figure 2.Saw silk 1 is on guide wheel 6, and non-conductive hard brittle material crystal bar 4 is fixed on the workbench 7 by anchor clamps 5.On the one hand, saw silk 1 carries out unidirectional under the drive of driving mechanism (this driving mechanism can adopt the driving mechanism of the multi-thread saw silk of existing free abrasive microtomy) or moves back and forth, and realizes main cutting movement.Saw silk 1 can adopt free abrasive saw silk or concretion abrasive saw silk.Simultaneously, saw silk 1 and guide wheel 6 are realized feed motion along moving perpendicular to the direction of the main cutting movement of sawing silk 1.On the other hand, on workbench 7, piezocrystal transducer is housed, drive piezocrystal transducer work by supersonic generator, make workbench 7 produce attached supersonic vibration, the direction of this vibration is consistent respectively with saw silk 1 main cutting movement direction and direction of feed both direction.Two piezocrystal transducers perhaps are housed on workbench 7, a piezocrystal transducer makes workbench 7 produce direction and the consistent attached supersonic vibration of the saw main cutting movement direction of silk, and a piezocrystal transducer makes workbench 7 produce direction and the consistent attached supersonic vibration of saw silk direction of feed.Said method is that crystal bar 4 is fixed on the workbench 7, and with workbench 7 vibrations, 1 pair of crystal bar 4 of saw silk cuts in the time of vibration.Also can between workbench 7 and crystal bar 4, ultrasonic vibration installation be installed, only make crystal bar 4 produce vibration.
Method of the present invention is mainly used in the section of valuable hard brittle materials such as monocrystalline silicon, polysilicon, quartz crystal, SiC crystal, sapphire crystal, is specially adapted to the SiC crystal of extreme hardness, the cutting processing of sapphire crystal.It is a kind of crystal-cut method of high-efficiency and precision.