CN101186082A - Method for using multi lane cutting machine to cut a plurality of thin silicon chip along radial direction once time - Google Patents

Abstract

The invention discloses a method which once cuts a plurality of thin silicon leaves in radial direction by a multi-line cutting machine, comprising the following steps: 1) a lead washer and the thin silicon leaves to be cut are alternatively and densely piled to form an integrated workpiece which is then attached to a colophony bar; 2) the bonded integrated workpiece is fixed on the multi-line cutting machine; the cutting line aligns the gap between adjacent lead washers and the silicon leaves to be cut are cut into two parts along the gap. Two sides of the lead washer are provided with lead steps with the profile in H-shape. By adopting the lead washers, the invention changes the situation that a multi-line cutting machine can only cut longer ingot in radial direction and can not cut thin silicon leaves along radial direction. In the production process of silicon polishing leaves with heavy mixed diffusion layers, the electric consumption of each leaf can be reduced by about 50% by adopting the method of the invention.

Description

The method of a plurality of thin silicon chip along radial direction once time being cut with multi-line cutting machine

Technical field

The present invention relates to multi-thread cutting field, relate in particular to a kind of method of a plurality of thin silicon chip along radial direction once time being cut with multi-line cutting machine.

Background technology

Now, super large-scale integration nearly all is a Czochralski silicon wafer with backing material, the ever-larger diameters of silicon chip and high surface smoothness are the main directions of its development, and multi-thread cutting technique is improving aspect silicon chip flatness and the surface geometry parameter, compare with inside diameter slicer to have very big advantage.All be that whole section silicon single crystal ingot cut into certain thickness thin slice by multi-line cutting machine is disposable in multi-thread cutting in the past, thereby realize the batch cutting of silicon chip, consider the processing characteristic of multi-thread cutting technique, the silicon single crystal ingot that multi-line cutting machine cut is generally the rod of length 100～400mm.And in actual applications, a large amount of thin silicon sheets radially need be divided into two, to adapt to the specific use of silicon chip, this is difficult to realize in present multi-thread cutting technique.

Summary of the invention

The purpose of this invention is to provide a kind of method of a plurality of thin silicon chip along radial direction once time being cut with multi-line cutting machine.

Comprise the steps:

1) with the lead pad with wait that cutting the thin silicon sheet alternately closely stacks into an one-piece machine member, is bonded in this one-piece machine member on the resin streak again.

2) one-piece machine member that glues is fixed on the multi-line cutting machine, line of cut is aimed at the slit between the adjacent wires pad, cuts along this slit silicon chip to be cut is divided into two.

The both sides of described lead pad are provided with the lead step, and section shape is I-shaped.

The present invention alternately closely arranges a plurality of lead pads and silicon chip, and is bonded on the resin streak, is fixed on then on the multi-line cutting machine, with multi-line cutting machine the thin silicon sheet radially is divided into two, and cuts into the thinner silicon chip of twice quantity.Adopt this lead pad can change multi-line cutting machine and can only radially cut longer crystal ingot, and the situation that can not radially cut the thin silicon sheet in batches.In the silicon polished process of producing the band heavily doped diffusion layer, use the method for this invention, every power consumption can be reduced about 50%.

Description of drawings

Fig. 1 (a) is the silicon polished present preparation flow of band heavily doped diffusion layer;

Fig. 1 (b) is the silicon polished preparation flow of the band heavily doped diffusion layer behind employing the present invention;

Fig. 2 uses multi-line cutting machine cutting schematic diagram of the present invention;

Fig. 3 is the bonding schematic diagram of one-piece machine member that lead pad, silicon chip to be cut are formed;

Fig. 4 is that lead pad, silicon chip to be cut, line of cut mutual alignment concern schematic diagram;

Fig. 5 is a conductor pads chip architecture schematic diagram of the present invention;

Fig. 6 is lead pad, silicon chip to be cut, cutting gauze schematic three dimensional views;

Among the figure: workbench and clamping plate 1, connecting plate 2, resin streak 3, one-piece machine member 4, the first multi-wire cutting machine mortar mouth 5, the second multi-wire cutting machine mortar mouth 6, lead pad 7, line of cut 8, thin silicon sheet 9 to be cut, guide roller of multi-line cutting machine 10, lead step 11.

The specific embodiment

The method of a plurality of thin silicon chip along radial direction once time being cut with multi-line cutting machine comprises the steps:

1) with lead pad 7 with wait that cutting the thin silicon sheet alternately closely stacks into an one-piece machine member 4, again this one-piece machine member is bonded on the resin streak 3, the both sides of described lead pad are provided with the lead step, section shape is I-shaped;

2) one-piece machine member that glues is fixed on the multi-line cutting machine, line of cut is aimed at the slit between the adjacent wires pad, cuts along this slit silicon chip to be cut is divided into two.

In use, as shown in Figure 6, (thickness is less than 1-2mm with a plurality of these lead pads 7 and a plurality of silicon chip to be cut 9, be generally circular) alternately closely arrangement constitutes an one-piece machine member 4, be bonded on certain special-purpose resin streak 3, be fixed on the multi-line cutting machine (as Fig. 2 by connecting plate 2 and clamping plate 1 (concrete mode is different with the multi-line cutting machine model) then, shown in Figure 3), the slit that line of cut 8 is aimed between the adjacent wires pad 7, each seam is inserted a undercut secant, under the guiding of lead step 11, the thin silicon sheet radially is divided into two (as shown in Figure 4), cuts into the thinner silicon chip of twice quantity.This processing method can guarantee to cut the crystal orientation, thickness of silicon chip in the deviation that allows.Adopt this lead pad can change multi-line cutting machine and only be fit to the longer crystal ingot of cutting, and the situation that can not effectively radially cut the thin silicon sheet in batches.Adopt radially batch cutting thin silicon sheet of this lead pad and multi-line cutting machine, operation is simple.

The present invention also can be used for cutting square or rectangular thin silicon sheet, and cut direction is and axial vertical direction.The present invention also can be used for cutting the thin slice of other material.

The lead shoulder height h of lead pad of the present invention (as shown in Figure 5) ₁, determine by following formula:

${\mathrm{<figure-callout\; id="1"\; label="h"\; filenames="S2007101603896E00021.png"\; state="\{\{state\}\}">h</figure-callout>}}_1=\frac{w-d_1-{2\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="S2007101603896E00041.png"\; state="\{\{state\}\}">d</figure-callout>}}_2}{2}$

In the formula, w is a thickness of waiting to cut silicon chip, d ₁Be the diameter of line of cut, d ₂Average grain diameter for cutting sand.

Other key dimensions of lead pad shown in Figure 5 are determined as follows:

L1：0～30mm；

L2：20～50mm；

d：0.3～1mm；

L: the diameter of silicon chip to be cut (perhaps width) adds 1～20mm;

H: the diameter of silicon chip to be cut (perhaps length) adds 20～30mm;

Conductor pads sheet material of the present invention is ordinary steel, stainless steel or plastics.

Embodiment

In the manufacture process of some discrete device, the silicon polished replacement silicon epitaxial wafer that uses the band heavily doped diffusion layer to be reducing production costs, its manufacture process as shown in Figure 1, in diffusion furnace, N type (phosphorus) is slight to mix and (uses N ^-The two sides of silicon abrasive sheet expression) all is exposed in the diffusion atmosphere of phosphorus, and through long-time high temperature phosphorous diffusion, the two sides of silicon abrasive sheet all can form N type (phosphorus) the severe doped region of symmetry and (use N ⁺Expression).At present in the preparation flow that generally adopts (as Fig. 1 a) shown in), the silicon abrasive sheet after the diffusion removes one side severe doped region through the grinding attenuate and the polishing processing of single face, forms a slice and has N ^-/ N ⁺Structure silicon polished.After introducing the present invention,, radially be divided into two the silicon abrasive sheet after a plurality of diffusions is disposable earlier, again the cut surface of the silicon chip of the twice quantity that obtains carried out grinding and polishing and process, obtain the N that has of twice quantity with multi-thread cutting and lead pad process technology ^-/ N ⁺Shown in silicon polished (as Fig. 1 b) of structure).Improve raw-material utilization rate so to a great extent, and greatly reduced the device production cost.This invention is used to can reduce by 50% monolithic power consumption approximately with the silicon polished production of heavily doped diffusion layer.

The present invention is based on that the problem that run in as above the example creates.We have adopted the line of cut of special lead pad guiding multi-line cutting machine in invention, the thin silicon sheet of thickness less than 1～2mm can be divided into two, and have improved the utilization rate of silicon chip greatly, have reduced power consumption.

Claims (2)

1. method of a plurality of thin silicon chip along radial direction once time being cut with multi-line cutting machine, its characteristic is to comprise the steps:

1) with lead pad (7) with wait that cutting the thin silicon sheet alternately closely stacks into an one-piece machine member (4), is bonded in this one-piece machine member on the resin streak (3) again;

2) one-piece machine member that glues is fixed on the multi-line cutting machine, line of cut is aimed at the slit between the adjacent wires pad, cuts along this slit silicon chip to be cut is divided into two.

2. a kind of method of a plurality of thin silicon chip along radial direction once time being cut with multi-line cutting machine according to claim 1, its characteristic are that the both sides of described lead pad are provided with the lead step, and section shape is I-shaped.

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