CN101944478A

CN101944478A - Manufacture method of semiconductor wafer applied to integrated circuit

Info

Publication number: CN101944478A
Application number: CN2009101575132A
Authority: CN
Inventors: 郭淑龄
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-07-10
Filing date: 2009-07-10
Publication date: 2011-01-12

Abstract

The invention provides a manufacture method of semiconductor wafer applied to integrated circuit, comprising the steps of: providing an ingot casting; cutting the ingot casting into slices to form a plurality of wafers; irradiating the surfaces of the wafers by laser to remove the saw mark on the surfaces of the wafers caused by the cutting, meanwhile fusing the cracks on the surfaces of the wafers; and performing the following steps such as acid leaching, polishing, detecting the surfaces of the wafers and the like to the wafers. The invention uses the energy focus characteristic of the laser to remove the saw mark existing on the surfaces of the wafers, and realizes the fusion of the micro surface crack on the slices caused by stress during the cutting, thereby stopping the increasing of the damage layer caused by the characteristics of etching and the like in the following step of acid leaching, lowering the removal rate of the depth on the surface of the wafer, and further enhancing the wafer amount cut by one ingot casting.

Description

Be applicable to the manufacture method of the semiconductor crystal wafer of integrated circuit

Technical field

The present invention is that relevant a kind of crystal column surface is handled, and is meant a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit especially.

Background technology

In order to form the Silicon Wafer that can be applicable to the construction integrated circuit, need carry out various mechanical fabrication steps to the silicon ingot casting of column.See also Fig. 1, it is the flow chart of steps of making at present the semiconductor crystal wafer that is fit to be used in integrated circuit.The silicon ingot casting that provides of step S1 is provided as described in Figure, in regular turn; Step S2 cuts into slices the silicon ingot casting, and with formation sheet wafer, and the maximum kerf difference in height of wafer this moment on single is approximately 14～16um, two-sided about 30～45um; The bubble acid treatment of step S3, it is in order to eliminate stress, surperficial impurity, to widen the rift and the softener material structure, being beneficial to follow-up grinding processing procedure; The corase grind (lapping and/or grinding) that continues and carry out step S4; The cleaning of step S5; The polishing of step S6 (polishing); The cleaning of step S7; Steps such as the detection of step S8 can obtain can be applicable to the Silicon Wafer of construction integrated circuit, and carry out shipment.In above-mentioned processing procedure, the flaw layer (damage layer) that Silicon Wafer is produced for the kerf removing the surface and the time produced because of cutting and bubble acid back, always the amount of removing thickness reaches 130～150um.This makes whole wafer material thickness mostly be wasted in the flaw layer that tropism such as bubble acid treatment Shi Zhi caused constantly and removes, single wafer need be reserved bigger thickness when cutting in view of this, remove for follow-up grinding, so the wafer number that single ingot casting can cut into is less.

In view of this, the present invention satisfies the disappearance at above-mentioned known techniques, proposes a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit, effectively to overcome these above-mentioned problems.

Summary of the invention

The present invention's main purpose is providing a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit, it is after the section of silicon ingot casting forms the sheet wafer, crystal column surface is carried out whole formula laser irradiation, remove and simultaneously the microcrack of crystal column surface is merged with kerf crystal column surface, reduce kerf difference in height on the existence of microcrack and the crystal column surface by this, and make the back processing procedure steep sour Shi Zhi etc. to etch effects, because of microcrack merges, make flaw layer minimization, and then the total amount of removing of the flaw layer thickness when reducing wafer manufacturing, reach the wafer amount that improves single ingot casting institute energy output, reduce the use amount of moist solution on the processing procedure and speed output capacity.

For reaching above-mentioned purpose, the invention provides a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit, its step includes provides an ingot casting; Ingot casting is cut into slices, to form several wafers; Utilize laser irradiation crystal column surface, merge because of section kerf that is produced and the crack that makes crystal column surface to remove this crystal column surface; And this wafer is being steeped steps such as acid, polishing and detection.

Under illustrate in detail by specific embodiment, when the purpose that is easier to understand the present invention, technology contents, characteristics and the effect reached thereof.

Description of drawings

Fig. 1 is the manufacture method flow chart that is applicable to the semiconductor crystal wafer of integrated circuit at present.

Fig. 2 is the manufacture method flow chart of the present invention's semiconductor crystal wafer of being applicable to integrated circuit.

Fig. 3 is OM (light microscope) photographic view of the crystal column surface recess after the present invention's laser merges.

Fig. 4 is OM (light microscope) photographic view at the protruding place of crystal column surface after the present invention's laser merges.

Fig. 5 is OM (light microscope) photographic view that merges the crystal column surface of back without the present invention's laser.

Fig. 6 is OM (light microscope) photographic view of the crystal column surface after the present invention's laser merges.

Embodiment

The present invention's spiritual place is an energy focusing characteristic of utilizing laser, the kerf (saw mark) that section back crystal column surface is existed removes, the hallrcuts (micro surface crack) that stress produces in the time of will cutting into slices simultaneously merges (fusion), and then reduce the back processing procedure and steep sour Shi Zhi etc. to etch effects, make flaw layer minimization, the person saves corase grind (lappingor grinding) formality when more can make wafer manufacturing, reduce the amount of removing of thickness, and then improve the wafer number that single ingot casting can cut into.

See also Fig. 2, it is the manufacture method schematic diagram of the present invention's the semiconductor crystal wafer that is applicable to integrated circuit.As shown in the figure, carry out in regular turn step S11 described a silicon ingot casting (wherein the material of this ingot casting also can be GaAs or germanium) is provided; What step S12 was described cuts into slices the silicon ingot casting, to form the sheet wafer; Step S13 described with wave-length coverage be 309 how rice～2140 how the laser of rice crystal column surface carried out whole formula laser shine (as single or scan back and forth mode), remove with kerf crystal column surface, the hallrcuts of crystal column surface also can absorb the effect of the energy generation fusion of laser because of the silicon material simultaneously, as shown in Figure 3 and Figure 4; Continue as described in the step S14, wafer steeped acid treatment, with eliminate stress, surperficial impurity and softener material structure, be beneficial to follow-up grinding processing procedure; Then as wafer being polished (polishing) as described in the step S15; Clean as the crystal column surface that carries out as described in the step S16, to remove remaining polishing agent or slurry on the crystal column surface; As the steps such as detection as described in the step S17, can obtain can be applicable to the Silicon Wafer of construction integrated circuit, and carry out shipment at last.

Under the fabrication steps of the invention described above, the maximum kerf difference in height of wafer on single that merges the back through laser is approximately 1～2um, two-sided also only about 2～4um, go up 14～16um of maximum kerf difference in height and 30 two-sided～45um compared to known single, the present invention can dwindle the kerf difference in height significantly, significantly to improve wafer surface roughness, moreover, because of when laser scans, having produced the hallrcuts fusion, therefore in the acid of the bubble in the step S14 processing procedure, just can not produce very big flaw layer because of the grade of pickle to etching at the sour processing procedure of bubble, and then reach and make flaw layer minimization as known techniques.

Under the present invention's fabrication steps, the thickness of wafer is the amount of removing 10～20um only always, therefore can omit the corase grind fabrication steps in the prior art.But certainly whether omits visual processing procedure and suitably adjusts, thus roughly grind step have or not can not as with the separating of the present invention.

Utilize under the present invention's the fabrication steps, per unit silicon ingot casting can the more Silicon Wafer of output, can increase by 20% approximately.Person more can reduce the use amount of moist solution on the processing procedure, omits 50% approximately.Moreover the rate that removes of minimizing Silicon Wafer speeds output capacity, improves 60% approximately.

Table one: it is a variation table as a result of handling the crystal column surface difference in height of front and back through the present invention's laser, laser is to adopt 532 green lasers of rice how in this experiment, certainly also can adopt other light source laser for example purple light, ruddiness etc., wave-length coverage is 309 rice～2140 rice how how.

The above person only is the present invention's preferred embodiment, is not the scope that is used for limiting the invention process.Event is all according to the present patent application scope described impartial for it variation of feature and spirit institute or modification, all should be included in the present invention's the claim.

Claims

1. manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit, it is characterized in that: its step includes:

One ingot casting is provided;

This ingot casting is cut into slices, to form several wafers;

Utilize a laser that this crystal column surface is shone, merge because of section kerf that produces and the hallrcuts that makes this crystal column surface to remove this crystal column surface; And

This wafer is steeped steps such as acid, polishing and detection.

2. according to 1 described a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit of claim the, it is characterized in that: wherein the material of this ingot casting is silicon, GaAs or germanium.

3. according to 1 described a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit of claim the, it is characterized in that: wherein the wavelength of this laser is 309 rice～2140 rice how how.

4. according to 1 described a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit of claim the, it is characterized in that: wherein this laser is that wavelength is 532 green lasers of rice how.

5. according to 1 described a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit of claim the, it is characterized in that: a corase grind step wherein more can be arranged between this bubble acid and this polishing step.

6. according to 1 described a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit of claim the, it is characterized in that: the step that a wafer clean wherein more can be arranged between this polishing and this detection step.

7. according to 1 described a kind of manufacture method that is applicable to the semiconductor crystal wafer of integrated circuit of claim the, it is characterized in that: wherein this laser can be that single scans or scans back and forth.