CN86100381A - Solar battery array - Google Patents

Abstract

The present invention relates to a kind of solar array that forms by the soft aluminium foil of a pair of electrically insulated from one another that separates.The P type semiconductor ball of band N type shell is fixed on a slice to be had on the aluminium foil of oxidation coating, and is coupled with electric the going up of two aluminium foils respectively.Before conductor oxidate was removed in mechanical lapping, semiconductor spheres contacted another sheet material.During 500～577 ℃ of sheet materials, ball is pressed into the etch-hole on the sheet material, form many such arrays on tape, indent locations put pad and above indentation array is separated separately, so sheet material just has flange to reach the sheet material that the outside connects another array, constitute the large-sized solar plate with these many arrays by the interconnection of rolling form.

Description

Solar battery array

The present invention relates to be arranged in the method for making solar cell on the silicon sphere of a tinsel matrix, above-mentioned battery produces electric energy when illumination.

People have known the energy-producing system that sunlight is converted to other forms of available energy, owing to comprised that the sun of main energy sources has economy, such device is constantly developed and improvement.The Kiel than (Kilby) etc. at United States Patent (USP) 4; 021; disclosed a kind of such system in 323, wherein the solar array of being made up of glass or these transparent bases of plastics is P type silicon grain to be provided or to imbed that P type shell surface provides N type silicon grain on the one side of matrix to N type shell surface on the one side of imbedding matrix.Although these arrangements can change, it is to have the P type silicon grain of N type shell and other are the N type particles with P type shell that half particle is preferably arranged.At the back side of matrix, once the silicon particle of there protuberance with suitable on electric the metallization of conduction connect mutually.The silicon particle has the housing parts that extends by the matrix front.These arrays are dipped into electrolyte preferably in the oxygen bromic acid (HBr), the front of its contact matrix.Have potential difference owing to contact between the different silicon grain of electrolytical conductivity type, form potential difference betwixt under sunlight, this moment, hydrobromic acid was electrolyzed to produce hydrogen and bromine, and hydrogen bubbles over, and bromine is then stayed in the solution.For example, known at fuel cell with similarly in the situation, hydrogen is collected and becomes the energy.

Such solar array, the silicon particle participates in electrolysis separately.Its result is not if the P-N of very small particles knot short circuit or by bypass makes significant difference for the speed that is produced product by array.

Another system that is used for producing from sunlight available energy uses the array similar to the above-mentioned type, can not carry out electrolysis and just produces electric charge but be connected into.United States Patent (USP) 2,904 has disclosed such system No. 613.Though, might alternately arrange, useful embodiment comprises the transparent base as glass or plastics, provides the particle of the N type silicon with P type shell.The N core of particle through matrix back side projection and by suitable on electric the metallization of conduction be coupled to each other.P type shell interconnects through the such light-guide material of conduction on electric of the tin oxide on the metal-gate structures of matrix front projection.Under the sunlight effect, between being connected to each other of the back side of this an array and front, form potential difference, this array can be connected into the direct outside electric loading that drives suitably.

Kent R Carson has made improvement to prior art in 562,782 the application, wherein further improvement has also been done in above-mentioned invention.Yet in the prior art, the expense of making solar array according to above-mentioned prior art is quite uneconomic, does not see also that so far the method for this prior art obtains very ten-strike economically.Therefore, pressing for provides economically feasible solar array, so that can relatively not too expensively make such array.

According to the present invention, a method of making solar battery array is provided, wherein reduce the problem of mentioning in the above-mentioned prior art widely, and compare with the prior art of enumerating, can make solar battery array more economically.

In brief, according to the present invention, solar battery array has natural aluminium oxide with providing the flexible aluminium foil of first standard type to make on the surface of standard type aluminium foil table, and those local pressures that make this paper tinsel lay the silicon ball are carved so that form metallic matrix.Clean with organic substance then and those thin facets of erosion removal, and produce aperture within it so that the position of inserting the silicon ball to be provided.With an additional corrosion step so that on paper tinsel, produce coarse surface.Paper tinsel forms the housing of putting ball, also as preceding contact.The silicon ball that has N type shell on the P type is attached the back side at paper tinsel, provide vacuum cup ball to be inhaled aperture on limit, hole and part ball elder generation inspiration paper tinsel in the front of paper tinsel, so that cut off the passage that air flows through aperture.Because use the ball excessive at first with respect to hole count, so, all to be filled up the no ball that cleans with a brush then, or the back of the body surface of similar paper tinsel behind all Kongzuis by ball.

Then, the ball punching press is bonded on the aluminium foil, stamping press is driven to ball in the hole according to the big garden of the ball that is positioned in the paper tinsel front, is positioned at the front (towards the one side of the sun or light) of paper tinsel.Force ball to cause that to the power in the hole aluminium foil tears on the surface that contacts with the silicon ball in brute force, and the exposed aluminium that makes new advances, because the silicon ball also can blow oxide on surface off and exposed new aluminium with respect to the shear action of the motion generation of aluminium, in fact, this effect also can be got on except that silica with the part surface of the ball that touches with the particularly exposed lead joint of aluminium foil.About 500 ℃ in less than 577 ℃ temperature range, this effect can take place in aluminium, though at this temperature aluminium solid, but be easy to be out of shape and silicon remains rigid body.(if the punching press time is enough to of short duration, temperature may above 577 ℃), new aluminium invasion and attack silicon dioxide and during punching press, again it being walked from the pressing part displacement in fact.Thereby provide bonding between the sial to form contacting of aluminium and silicon N type shell by this way.Then, the paper tinsel ball array is cooled to ambient temperature, rehardens to allow paper tinsel.

Then, corrosion has the back side of the paper tinsel of exposed ball, to remove N type shell there.Because aluminium foil is as the case of silicon etchant, and paper tinsel is not because the very thin natural oxide of one deck that has nature to form itself is very active.Array is placed on does about half a minute of anodization in the sulfuric acid tank (about 10% sulfuric acid), on aluminium, to produce an oxide covering, then with another anodization groove, wherein fill half phosphoric acid of 1% with sealing aluminium and make the silicon anodization, generate the silicon dioxide of about 10 microns alundum (Als and 0.1 micron here approximately.The back of the body surface of mill ball makes it produce the surface that can contact with it then.Grinding technics makes rough surface so that forms a good impedance contact.Being preheating to 500 ℃, second thin aluminium foil is put into lapped face then, aluminium foil is stamped into abrasive areas forms the surface of contact with it extremely less than 577 ℃ temperature range.

In this process, array is to generate in a mode of rolling up, and places shell between two aluminium foils between the array that adjoins before on being located at second aluminium foil hitch ball.In this scheme, above and the following all stressed effect of paper tinsel, but be not to connect, and second aluminium foil and ball are bondings with other shell.Aluminium foil is rule suitably on the shell on the both sides of array then, thereby the extending part of a paper tinsel all is provided for each limit on array two opposites.The extension of aluminium foil can connect together to generate a kind of amplifying circuit with series circuit relation then.

The array that has shell can be rule, and cuts apart mutually and chamfering, so Yi Bian rectangular array in the type of attachment had only outward extending second aluminium foil part arranged.These contacts are connected with first aluminium foil of the array of other Any shape, have input and the module of exporting thereby provide.

Conclusion is that the solar array with the projection that exposes each silicon ball on the array front provides the active surface that increases the absorption sunray.Further conspicuous cheap material and the technical process of having utilized a relative small number provides such softness, and the array of a reflective optical system is arranged on aluminium foil.

Fig. 1 is a process flow diagram of making solar array according to the present invention.

Fig. 2 is the process schematic representation of Fig. 1 flow process.

Fig. 3 is array interconnects program in the one dimension direction a schematic diagram.

Fig. 4 is array interconnects program at two dimensional surface a schematic diagram.

Fig. 5 is array interconnects program at three dimensions a schematic diagram.

Fig. 6 is according to component drawings of the present invention.

See figures.1.and.2, as seen utilize characteristics of the present invention to make the solar array process flow diagram according to the present invention.Begin, prepare the aluminium foil [1] of about 2 mil thick, aluminium foil [1] is flexible, has a very thin natural oxide layer to be exposed to environment naturally in its surface usually simultaneously.When being conceived to single solar array element, should be understood that as prior art before this is illustrational that total array is to be combined by single array element with the explanation here.

Shown in [a], aluminium foil [1] is pressed into periodic hexagon at first earlier.For example, its centre is 16 Mills and has the pressure facet [3] that reduces thickness that its diameter is more smaller than the sphere diameter that will be seated in the inside.Pressing facet can be garden shape or other geometries, as hexagon.Pressing facet is under the polygonal situation, will be less than the diameter that is used to put ball by the line at this polygon center.Then as [b].Shown in, clean paper tinsel to remove organic substance, with the zone of pressing facet [3] on NaOH that heats or the potassium hydroxide etch paper tinsel and at this local aperture [5] that forms.During etching, press facet [3] to be removed prior to the residue on the paper tinsel, because press facet [3] thinner,, and owing to when pressing quarter, it carried out cold working so also etching gets soon than the residue of paper tinsel.This is called aluminum substrate.

This moment, paper tinsel can be selected for use 50% 39A etching solution to carry out etching to make it have certain structure (etchant 39A is 15% hydrogen fluoride, 60% nitric acid and 15% glacial acetic acid), thereby provided one to make backside reflection reduce to minimum matrix surface.

Many silicon balls [7] that have N type shell [9] and P type inner core [11] shown in (C) are placed on the back side [13] of the matrix on the paper tinsel [1], and provide a vacuum to use vacuum cup ball [7] inlet hole [5] in the front [15] of paper tinsel.Because the ball [7] excessive with respect to hole [5] number is used for the back side of paper tinsel at first, all holes all will be filled by ball [7], with brush or other similar methods excessive ball [7] be removed from the back side of paper tinsel then.Here the diameter of the ball of Li Yonging 14.5 Mills preferably, as mentioned above, the diameter of section of hole [5] is less than 14.5 Mills, thereby provides a vacuum in the front of paper tinsel for paper tinsel, and its reason illustrates hereinafter.

Ball [7] is bonded in the hole [5] of the aluminium foil [1] shown in (d), heat this paper tinsel, going up at ball [7] then makes it enter hole [5] fast with a surge, cause a shear action in the inside in hole, it scrape off paper tinsel on the limit, hole the inner surface place aluminium oxide and expose fresh element aluminum.Because illustrated, aluminium has been heated to about 530 ℃ temperature, and at this moment, ball [7] is pressed into hole [5], so aluminium is active, and more or less sticking and easy deformation on mechanical performance.Therefore very thin natural silicon oxide layer reaction and it is removed on element aluminum and the ball, thus the aluminium on the present paper tinsel [1] on can the N type shell [9] of Direct Bonding ball silicon and form contact.

Ball [7] is placed in the hole [5], so its big garden line is in the front of paper tinsel [1] or on its front [15].Can realize such arrangement with being placed on above the aluminium foil [1] with following pressure pad.Pressure pad is to make with the aluminium foil that scribbles such as about 8 mil thick of the such releasing agent of boron nitride powder.It as cushion pad at the unlikely ball that washes out of impact epoch chien shih stamping hammer.In addition, pressure pad absorbs the bump of hammer.Top pressure pad on the face (13) of paper tinsel (1) is thicker than the bottom pressure pad on paper tinsel (1) face (15), so that the displacement of big garden on paper tinsel (1) of ball as mentioned above to be provided.To one 2 square centimeters array, operate with the impact energy of about 48 Foot-Pounds and to succeed.So as the above, present aluminium directly is attached to silicon and has been got on.

Then, shown in (e),, remove the array upper rear portion and divide N type layer (9) and expose p type island region with 39A etchant etching paper tinsel (1) back side (13) and the spherical calotte on this one side.The aluminium foil (1) that has a native oxide as a protective cover, only allows to remove the part layer (9) at the array back side (13) to the effect of etchant.Remove etchant with the rinsed with deionized water array then, shown in (f), again array is made anodization with the exposed silicon of passivation, paper tinsel is immersed pact half a minute in 10% the sulfuric acid solution under about 20 volts voltages.Paper tinsel is immersed in passivation half a minute in 0.5% the phosphoric acid solution under about 20 volts of voltages then.The required time of anodization is the function when electric current in the groove tends to be zero or cut-out, and this approximately is half a minute.Have been found that all necessary phosphoric acid that uses of oxide layer (21) for sealing the hole in the aluminium oxide and forming about 1000 dusts at original etched silicon face.

The ball (7) of the array of mechanical lapping anodic oxidation is gone up at the back side (21) that forms during anodic oxidation with the method for knowing then.This grinding silica (21) thereby and some silicon all remove the back side (1) of adjusting ball (7), and go up to produce a coarse surface in (17) and make it become ohmic contact.Shown in figure (h), on the topped back side in each ball (7) of thin aluminium foil (17) that is about 1/2 Mill, delay to handle to cause ground flat (17) then, aluminium is heated to about 530 ℃, is preferably in 500～577 ℃ of above-mentioned scopes.Then with surge the aluminium foil that heat (19) bears against ball (7), and owing to impact the aluminium expose and because grinding silicon and impact element aluminum are exposed to generation one bonding between the silicon on the back side of ball (7).Paper tinsel (19) is to form according to above-mentioned (d) bonding that uses the same method to the contact of silicon area (11).Because the anodic oxidation of aluminium foil (1), there is one deck thick-layer aluminium oxide on the surface of described paper tinsel, is short-circuited between paper tinsel (1) and paper tinsel (19) preventing.[shown in figure (i), can on the front surface of array, be coated with last layer standard antireflecting coating, to improve the light absorptive of silicon.] this shows that a solar battery array is provided, and wherein the major part of silicon ball has been exposed to the sunray of incident, the array of the inside is flexible, used technology and material are not expensive comparatively speaking and quantity is few.

In the actual process flow process, expose array and all be linked to be volume array supply rather than that separate separately, array becomes possible module then, 1 meter size of taking advantage of 2 meters for example, and test by this design, each array so that above-mentioned this method is made has 10 centimetres usually approximately on every limit.

Provide above-mentioned solar array to form module by the flow process that Fig. 3 to Fig. 6 illustrates then with the rolling form.Referring to Fig. 3, visible array is coupled to each other the one dimension schematic diagram of system earlier, and as seen, the single array (30) with ball (31) is positioned in the contact foil body (33) of front in Fig. 3 (a), and the paper tinsel body (35) at the back side is not also run into ball.Pad (37) is inserted between the array (30), sees clearlyer from Fig. 4 (a).From Fig. 4 (a) as seen, preceding paper tinsel (30) is smaller than back of the body paper tinsel (35), and its reason may be obvious that from below.

Referring now to Fig. 3 (b),, the paper tinsel (35) of can passing away contacts with ball (31) and pad (37), and top paper tinsel (33) also contacts with pad.This just finishes in Fig. 1 (h) step operation, and back of the body paper tinsel (35) is bonded to ball (31) also as the part of this operation.Paper tinsel (35) and (35) will be not and pad (37) bonding, only are contacts, and paper tinsel is delineated on the position of the V-arrangement spare on the pad of Fig. 3 (6) then, so that the arrangement that provides after removing with pad as Fig. 3 (c) and Fig. 4 (b) to be provided at array.Then, at Fig. 3 (c) and 4(b) being seen array chamfering becomes shown in Fig. 4 (c) so that four flanges to be provided, and these flanges are parts of back of the body paper tinsel (35), and be placed on each limit of array square formation, put on A, B, C, D is then B, C, D folds into and looks like under the array shown in Fig. 3 (d) and Fig. 4 (d), then with ultrasonic bonding or similar approach as 3(e) shown in guarantee A is connected to the flange B of next array, C like that, among the D one makes array become continuous array.

Can provide as shown in Figure 5 three-dimensional arrangement with mutual connection procedure, an array that wherein has stretch flange formability A is positioned, flange A connects the flange B of next array like this, among C or the D one, continue continuously to finish whole module with such program in a straight line direction or other approach, the B of the array that adjoins (30) that complex modules flange A as shown in Figure 6 is fixing provides a front and back passage on C or the D flange, this passage forms the series circuit with 60 this arrays.Also can be provided as and lead to the flange of module importing (41) and output (43).

After finishing the module of Fig. 6, just do test according to Fig. 2, if test successfully, just can be installed in module on back of the body carrier material or the materials similar, flange is bonded together with ultrasonic bonding at the bonding place then, after this, module sealing is to provide suitable environment sealing, seal modules is tested by standard method again then, thereby provides spendable module for the user.

Though the present invention is described most preferred embodiment especially, it is conspicuous having many distortion and improvement that those are known this professional people.Therefore, its request claim expands to and comprises that all comprise all various distortion and improved wide as far as possible scope from prior art.

Claims (25)

1, a solar array comprises:

A has the aperture at many intervals in first aluminium foil layer,

B, many semiconductor components, each all has P type and N type zone, and the N type is connected to described first aluminium foil,

C, contact and the insulation of described first aluminium foil, and be connected to the p type island region territory.

2, solar array as claimed in claim 1, wherein said contact are second aluminium foils.

3, solar array as claimed in claim 2, wherein said semiconductor component is spherical.

4, solar array as claimed in claim 3, the big garden of wherein said semiconductor component are in the place ahead away from described first this face of aluminium foil of described contact.

5, solar array as claimed in claim 4 further comprises the lip-deep antireflecting coating of described first aluminium that places away from described contact.

6, a kind of method of making solar array, the step that comprises has:

A provides first aluminium foil,

B is forming aperture on the precalculated position on the described paper tinsel,

C is provided at the spherical semiconductor particle that has N type shell on the P type inner core,

D is connected to described N type zone to described paper tinsel in described hole,

E removes N type layer on the one side of described first paper tinsel,

F, the one side on described first paper tinsel forms an insulating barrier, and removes N type layer from this surface,

G removes the part of P core and the insulating barrier on it of described particle,

H is bonded to second aluminium foil in the zone of removing part P core.

7, method as claimed in claim 6, it is preceding further to be included in step (h), makes the regional coarse step of removing P core subdivision earlier.

8, method as claimed in claim 7 further is included in away from the step that forms an antireflecting coating on the described first paper tinsel surface of described second paper tinsel.

9, method as claimed in claim 8, wherein step (d) comprises that the front that described particle is seated in away from the described first paper tinsel surface of described second paper tinsel has in the described hole in the big garden of described particle.

10, a kind of semi-conducting material is bonded to the method that aluminium foil gets on, the step that comprises has:

A provides the aluminium foil of the aperture that has discontinuous interval in it,

B places the spherical semiconductor material in the described hole of adjoining,

C heats described paper tinsel and described material in about scope to 500 ℃,

D moves described material and enters described hole, moves described material under the effect of power, therefore is sheared to expose the primer that mutual bonding is used at described material and the lip-deep natural oxide of described paper tinsel.

11, method as claimed in claim 10, moving under wherein step (d) is included in and impacts.

12, a kind of semi-conducting material is bonded to method on the aluminium, the step that comprises has:

A provides al member,

B places semi-conducting material to adjoining described al member,

C heats described al member and described semi-conducting material, makes temperature in about 500 ℃ to 577 ℃ scope,

D forces described semi-conducting material to enter described al member, under impacting, at shock point exposure element aluminium and semi-conducting material.

13, method as claimed in claim 12 further is included in step (d) back cooling semi-conducting material and the al member step to ambient temperature, to form bonding between described al member and described semi-conducting material.

14, method as claimed in claim 12, semi-conducting material wherein is a silicon.

15, a kind of manufacture method that on aluminium foil, forms the hole array, the step that comprises has:

A, the aluminium foil that provides the surface to have thin-oxide,

B, the precalculated position of suppressing described paper tinsel does not connect interval region to be provided at the zone that reduces thickness in the described paper tinsel on described press face.

C along the described paper tinsel of all surfaces etching of described paper tinsel, reduces the described zone of thickness with removal, to form the hole in the described location that reduces thickness on described paper tinsel.

16, a kind of method that on the silicon body, forms contact, the step that comprises has:

A, the silicon material that provides the surface to have oxide layer,

B, machinery is removed the part of described oxide layer and described silicon material,

C, the zone removing the silicon material provides rough surface on the silicon material,

D is bonded to described rough surface to contact when heating,

17, a kind of method as claimed in claim 16, wherein said contact is the aluminium contact.

18, method as claimed in claim 17, wherein said silicon material is spherical, described contact is a paper tinsel.

19, the method for a kind of anodic oxidation and sealed aluminum and semiconductor material combinations thing comprises that step has:

A provides and the corresponding al member of semi-conducting material,

B forms oxide covering on described al member,

C, the described member that anodic oxidation obtains from figure (b) be about half a minute in about 0.1% phosphoric acid solution, with sealed aluminum and the described semi-conducting material of oxidation.

20, method as claimed in claim 19, wherein step (b) comprises described al member is placed on half a minute in 10% sulfuric acid tank.

21, a kind of method of etching silicon material, the step that comprises has:

A provides described silicon material,

B with natural oxide coated aluminium, shelters described a part of material and makes it not etched,

C uses the described material of etchant etching for the suitable inertia of described oxide.

22, a kind of method as claimed in claim 21, wherein said etching step are to use the etchant of being made up of hydrogen fluoride, nitric acid and glacial acetic acid to provide.

23, a kind of array interconnection sytem comprises:

A, a pair of compliant conductive aluminium foil with the mutual electric insulation of natural oxide,

B, many silicon balls with zone of p type island region territory or N type, described each zone is coupled one by one with described aluminium foil respectively and is fixed on each described aluminium foil, and flows through electric current between paper tinsel

24, a kind of array as claimed in claim 23 further comprises one second array, and described one side is electrically connected with described second array a slice from extending in described array outside.

25, a kind of method that forms array interconnect, the step that comprises has:

A, provide a pair of flexibility that separates apart from one another by conductive sheet, electronic component is arranged in the middle of it,

B, indentation forms array on described sheet material, one side consequently a part of sheet material is in the back that extends to another sheet part of array, the another side of a part of array of another sheet extends to the back of a part of sheet material again.

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