CN102586779A

CN102586779A - Liquid-separation type wet etching device for silicon wafer

Info

Publication number: CN102586779A
Application number: CN2011103920045A
Authority: CN
Inventors: 胡江生
Original assignee: Changzhou EGing Photovoltaic Technology Co Ltd
Current assignee: Changzhou EGing Photovoltaic Technology Co Ltd
Priority date: 2011-11-30
Filing date: 2011-11-30
Publication date: 2012-07-18

Abstract

A liquid-separation type wet etching device for a silicon wafer comprises an etching groove, etching liquid, a mist absorbing tube and liquid absorbing rollers. The liquid absorbing rollers are arranged on an upper end face in the etching groove at equal intervals and at the same height. A liquid level of the etching liquid is higher than lower end faces of outer circles of the liquid absorbing rollers and lower than the axis of the liquid absorbing rollers. The mist absorbing tube is arranged between the two liquid absorbing rollers and arranged above the etching liquid and below the upper end faces of the outer circles of the liquid absorbing rollers. An air absorbing hole is arranged on an upper lateral side of an outer circle of the mist absorbing tube, the mist absorbing tube is connected with an air suction machine, polluted area around the silicon wafer is greatly reduced, the upper end face can not be polluted, accuracy of an etching area is guaranteed, process control is easy, etching effect is stable, qualified products of etching are greatly increased, working environment is further improved, and damage of etching liquid mist on operators is avoided.

Description

A kind of from liquid formula silicon chip Wet-method etching device

Technical field

The present invention relates to the etching device of crystal silicon solar batteries silicon chip, relate in particular to solar battery sheet silicon chip Wet-method etching device.

Background technology

Lithographic technique is considerable step in the solar battery sheet ME.Etching is divided into dry etching and wet etching.Dry etching general using plasma body carries out the etching of material, and each is good with the tropism, controllability is high, but cost is higher, complex equipments.Wet etching is a pure chemical reaction process; Utilize solution and in advance the chemical reaction between the etching material remove the part that not masked mould material shelters and reach the etching purpose; Because good reproducibility, low cost, production efficiency are high, equipment is simple, in the solar cell industry, be used widely.In the solar battery sheet manufacturing processed, the main purpose of wet etching is to remove the diffusion back side to reach electroconductibility silicon all around, prevents electric leakage; Strengthen back side smooth degree simultaneously, the experiment proof can further improve open circuit voltage, increases battery efficiency.At present, at home in the solar module manufacturing enterprise, most etching machines that adopt German RENA company to develop; It is to utilize to be stained with the liquid mode and to carry out wet etching; It comprises etching bath and delivery roller, and its etching principle is as shown in Figure 1, places the corrosive fluid of capacity in the etching bath; Make the silicon chip that is positioned on the delivery roller swim on the corrosion liquid level; Corrosive fluid corrodes around the silicon chip and the back side, is immersed in the translation transmission that subsurface delivery roller drives silicon chip, controls etching time through regulating the delivery roller rotating speed.Because this device utilizes the corrosive fluid surface tension to control etch areas and pattern; Very high to environmental requirements such as the viscosity of etching liquid, equipment air drafts, the less stable of etching, technology is wayward; And etching solution also overflows to the front of silicon chip easily, causes the reduction of efficient.In addition, etching bath is owing to be in the enclosed environment, and the silicon chip front is surrounded by a large amount of etching solution fogs, and etching solution fog corrodes positive generation of silicon chip easily.

Summary of the invention:

The invention provides that a kind of it can increase substantially the stability of wet etching from liquid formula silicon chip Wet-method etching device, technology controlling and process is simple, can avoid the corrosion of etching liquid volatile matter to silicon chip front PN junction simultaneously, improves battery efficiency.

Technical scheme of the present invention is:

A kind ofly comprise etching bath, etching solution, suction mist pipe and imbibition roller from liquid formula silicon chip Wet-method etching device, the imbibition roller uniformly-spaced is installed in the upper surface in the etching bath equal altitudes; The liquid level of etching solution is higher than the lower surface of imbibition roller cylindrical, is lower than the axis of imbibition roller, inhales the mist pipe and is arranged between two imbibition rollers; And be positioned on the etching solution; Under the upper surface of imbibition roller cylindrical, on the cylindrical upper side of inhaling the mist pipe, be provided with suction hole, inhale the mist pipe and link to each other with suction fan.

Further, said imbibition roller is the sponge wheel of being processed by SE, and its diameter is 60mm～80mm.

Further, the distance of the centre compartment between the adjacent two imbibition rollers is 80mm-85mm.

Further, the liquid level of etching solution is 1/5～4/5 of an imbibition roller radius apart from the distance of imbibition roller axis.

Because the cylindrical upper side with the imbibition roller among the present invention exposes on the liquid level of etching solution, the imbibition roller can drive on the lower surface that etching solution is coated in silicon chip equably, and the contact probability with etching solution around the silicon chip reduces significantly; The upper surface of silicon chip can not contact with etching solution, and the fog that etching solution produces in etching process is absorbed by inhaling the mist pipe, makes that so contaminated area dwindles significantly around the silicon chip; The upper surface can not polluted, and has guaranteed the accuracy of etch areas, has stablized the etching quality; The consumption of etching solution is few, and the workload of the subsequent disposal behind the silicon chip erosion reduces, and the defective that exposes in the existing etching technics all is able to overcome; Got rid of dependence to various outside labile factors; Technology controlling and process is simple, and etching effect is stable, and the salable product of etching increase substantially; Can also further improve Working environment, prevent that etching solution fog from injuring the operator.

Description of drawings:

Fig. 1 is the part-structure synoptic diagram of existing etching apparatus;

Fig. 2 is a structural representation of the present invention;

Fig. 3 inhales mist tubular construction synoptic diagram;

Fig. 4 is the imbibition roller and the synoptic diagram that is connected of variator;

Among the figure, the 1-etching bath; The 2-delivery roller; The 3-etching solution; The 4-silicon chip; 5-inhales the mist pipe; 6-imbibition roller; The 7-variator; The 51-suction hole.

Embodiment:

Below in conjunction with description of drawings embodiment of the present invention.

A kind of from liquid formula silicon chip Wet-method etching device, like Fig. 2, shown in Figure 3, comprise etching bath 1, etching solution 3, inhale mist pipe 5 and imbibition roller 6; The length of etching bath 1 is controlled at 2000mm, and the degree of depth is controlled at 500mm, width 600mm; Imbibition roller 6 uniformly-spaced is installed in the upper surface in the etching bath 1 equal altitudes, and its diameter is 80mm, and it is the sponge wheel of being processed by SE; The liquid level of etching solution 3 is positioned under the axis of imbibition roller 6, is 15mm apart from the distance of the axis of imbibition roller 6, inhales mist pipe 5 and is hollow tubular; Its diameter is 20mm, inhales mist pipe 5 and is arranged between adjacent two imbibition rollers 6, inhales the axis of mist pipe 5 and the axis of imbibition roller 6 and is in same plane; On the cylindrical upper side of inhaling mist pipe 5, be provided with suction hole 51, as shown in Figure 4, imbibition rollers 6 all in the etching bath 1 drive by variator 7; The rotating speed of imbibition roller 6 can be regulated according to effect, and the suggestion rotating speed is 1.5n/min.In etching process, etching solution 3 adopts the common process etching solution to get final product, and is generally HF/NNO ₃System; Imbibition roller 6 rotates in etching solution 3, absorption etching solution 3, when silicon chip 4 transmit on imbibition roller 6 with its on the etching solution that adsorbs 3 generation chemical reactions; Inhale mist pipe 5 and be connected to suction fan after the pooling, volatile gases sucks emission-control equipment through suction hole 51 by suction fan.

Claims

1. one kind is left liquid formula silicon chip Wet-method etching device; It is characterized in that: comprise etching bath (1), etching solution (3), inhale mist pipe (5) and imbibition roller (6), imbibition roller (6) uniformly-spaced is installed in the upper surface in the etching bath (1) equal altitudes, and the liquid level of etching solution (3) is higher than the lower surface of imbibition roller (6) cylindrical; Be lower than the axis of imbibition roller (6); Inhale mist pipe (5) and be arranged between two imbibition rollers (6), and be positioned on the etching solution (3), under the upper surface of imbibition roller (6) cylindrical; On the cylindrical upper side of inhaling mist pipe (5), be provided with suction hole (51), inhale mist pipe (5) and link to each other with suction fan.

2. according to claim 1 a kind of from liquid formula silicon chip Wet-method etching device, it is characterized in that: said imbibition roller (6) is the sponge wheel of being processed by SE, and its diameter is 60mm～80mm.

3. according to claim 1 a kind of from liquid formula silicon chip Wet-method etching device, it is characterized in that: the centre compartment distance between the adjacent two imbibition rollers (6) is 80mm-85mm.

4. according to claim 1 a kind of from liquid formula silicon chip Wet-method etching device, it is characterized in that: the liquid level of said etching solution (3) is 1/5～4/5 of imbibition roller (a 6) radius apart from the distance of imbibition roller (6) axis.