JPS60201670A - Solar cell - Google Patents
Solar cellInfo
- Publication number
- JPS60201670A JPS60201670A JP59059219A JP5921984A JPS60201670A JP S60201670 A JPS60201670 A JP S60201670A JP 59059219 A JP59059219 A JP 59059219A JP 5921984 A JP5921984 A JP 5921984A JP S60201670 A JPS60201670 A JP S60201670A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- solar cell
- type
- junction
- layers
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000013078 crystal Substances 0.000 claims abstract description 25
- 229910001218 Gallium arsenide Inorganic materials 0.000 claims abstract description 22
- 239000004065 semiconductor Substances 0.000 claims abstract description 22
- 239000000203 mixture Substances 0.000 claims abstract description 21
- 239000000758 substrate Substances 0.000 claims abstract description 20
- 239000000463 material Substances 0.000 abstract description 10
- 239000002131 composite material Substances 0.000 abstract description 8
- 238000009792 diffusion process Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 abstract description 4
- 238000005468 ion implantation Methods 0.000 abstract description 3
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 239000012535 impurity Substances 0.000 abstract description 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 239000004973 liquid crystal related substance Substances 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 52
- 238000006243 chemical reaction Methods 0.000 description 8
- 229910000980 Aluminium gallium arsenide Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 210000003127 knee Anatomy 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 239000000470 constituent Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Landscapes
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Photovoltaic Devices (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の技術的分野〕
本発明は、複合接合構造太陽電池に関し、特に、Ｓｉ基
板の使用により軽量化をはかると共に、各層半導体材料
の禁止帯幅の最適化をはかり、複数の太陽電池を積層す
ることにより光電変換効率を高めた太陽電池に関するも
のである。[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a composite junction structure solar cell, and in particular, aims to reduce the weight by using a Si substrate and to optimize the forbidden band width of each layer of semiconductor material. , relates to a solar cell with increased photoelectric conversion efficiency by stacking multiple solar cells.
従来の太陽電池の多くはＳｔ、 ＧａＡｓの同一材料が
ら成るｐｎ接合構造で構成されていた。これらの単一半
導体を用いている限りは、太陽光エネルギーを有効利用
できず、特に半導体の禁止帯幅より低エネルギーの光は
太陽電池内における光起電力発生に寄与し得す、単−接
合形太陽電池の光電変換効率は２０〜２２％が限界であ
る等の欠点があった。Most conventional solar cells have a pn junction structure made of the same materials, St and GaAs. As long as these single semiconductors are used, solar energy cannot be used effectively, and in particular, light with energy lower than the bandgap of the semiconductor can contribute to the generation of photovoltaic power within the solar cell. The photovoltaic conversion efficiency of solar cells is limited to 20 to 22%, which is a drawback.
また、第１図に示すように、太陽光に対するスベクトル
感度帯域を拡大し、高効率化をはかる目的で、ＧａＡｓ
１１ｍ結晶基板１上にＧａＡｓのｐｎ接合２から成る下
部太陽電池３とＡｌｇ、ｚＧａｇ、＠Ａｓのｐｎ接合４
から成る上部太陽電池５をＡ１０．Ｚにａｎ、＠へＳの
ｐ ＋ ｎ＋接合から成るトンネル接合６を介して接続
した太陽電池も提案されている。なお、図中、７は＾１
０．！１ＧａＬＩＡｓの窓層、８は反射防止膜、９電極
である。しかし、この太陽電池においては、上部太陽電
池５および下部太陽電池３の各構成材料ＡＩ Ｇａ Ａ
ｓ、ＧａＡｓの禁止帯幅が各々１ 、６５ｅＶおよび１
．４３ｅＶであるため、太陽光スペクトルの内１．４３
ｅＶよりも低エネルギーの光は太陽電池内における光起
電力発生に寄与し得ず、従って太陽光エネルギーを有効
利用できず、光電変換効率は１５〜１６％と単−接合形
太陽電池よりも低いなどの欠点があった。さらに、Ｇａ
Ａｓを太陽電池用基板として用いているため、高価格で
ＧａＡｓの密度が５．３１であるが故に重いという欠点
があった。In addition, as shown in Figure 1, GaAs
A lower solar cell 3 consisting of a GaAs pn junction 2 and an Alg, zGag, @As pn junction 4 on a 11m crystal substrate 1.
The upper solar cell 5 consisting of A10. A solar cell connected via a tunnel junction 6 consisting of a p + n + junction of an to Z and S to @ has also been proposed. In addition, in the figure, 7 is ^1
0. ! 1 is a window layer of GaLIAs, 8 is an antireflection film, and 9 is an electrode. However, in this solar cell, each constituent material of the upper solar cell 5 and the lower solar cell 3 is
s, GaAs band gap is 1, 65eV and 1, respectively.
．． Since it is 43eV, 1.43 out of the sunlight spectrum
Light with energy lower than eV cannot contribute to the generation of photovoltaic force within the solar cell, and therefore solar energy cannot be used effectively, and the photoelectric conversion efficiency is 15 to 16%, lower than that of single-junction solar cells. There were drawbacks such as. Furthermore, Ga
Since As is used as the solar cell substrate, it has the drawbacks of being expensive and heavy because GaAs has a density of 5.31.
このように、太陽電池の高効率化が検討されて来たが、
太陽光強度１００ｍＷ ／−に対するセル重量比出力で
換算すると、Ｓｉ太陽電池でＱ、５Ｗ／ｇ 。In this way, efforts have been made to improve the efficiency of solar cells, but
When converted to cell weight specific output with respect to sunlight intensity of 100 mW/-, the Si solar cell has Q, 5 W/g.
ＧａＡｓ太陽電池で０．３４Ｗ ／ｇと不十分であるな
どの欠点もあった。There were also drawbacks such as the insufficient power of 0.34 W/g for GaAs solar cells.
本発明は、これらの欠点を除去するためになされたもの
で、その目的は、複合接合構造太陽電池において、Ｓｔ
基板の使用を可能ならしめ軽量化をはかると共に、各層
半導体材料の禁止帯幅の最適化をはかり、複数の太陽電
池を積層することにより高効率でセル重量比出力の高い
太陽電池を提供することである。The present invention was made to eliminate these drawbacks, and its purpose is to provide a solar cell with a composite junction structure in which St.
To provide a solar cell with high efficiency and high cell weight specific output by making it possible to use a substrate and reducing its weight, optimizing the forbidden band width of each layer of semiconductor material, and stacking multiple solar cells. It is.
かかる目的を達成するために、本発明では、Ｓｉ単結晶
基板内あるいは該５ｉｊｌ結晶基板上にｐｎ接合を形成
して下部太陽電池を構成し、該下部太陽電池を、各々膜
厚４０〜１０００人のＧａＡｓと混晶半導体へｌｘ Ｇ
ａニー ｘ Ａｓ（ＡＩ組組成 ＝０．１〜０．９）の
２〜７層交互に成長させた中間層および混晶半導体Ａｌ
ｙＧａｘ −ｙ Ａｓ（ＡＩ組成ｙ＝０〜０．４）から
成るトンネル接合を介して混晶半導体ＡｌｚＧａｔ−χ
八５（Ａ１組成、−〇〜０．４）から成るｐｎ接合によ
る上部太陽電池と接続したことを特徴とする。In order to achieve this object, in the present invention, a pn junction is formed in a Si single crystal substrate or on the 5ijl crystal substrate to constitute a lower solar cell, and each of the lower solar cells has a film thickness of 40 to 1,000. lx G to GaAs and mixed crystal semiconductors
2 to 7 layers of a knee x As (AI group composition = 0.1 to 0.9) are grown alternately, and a mixed crystal semiconductor Al
Mixed crystal semiconductor AlzGat-χ
It is characterized in that it is connected to the upper solar cell through a pn junction consisting of 85 (A1 composition, -0 to 0.4).
Ｃ発明の詳細な説明〕
以下に、図面を参照しながら、実施例を用いて本発明の
詳細な説明するが、かかる実施例は本発明の例示に過ぎ
ず、本発明の範囲内で種々の改良や変形があり得ること
は勿論である。C Detailed Description of the Invention] Below, the present invention will be described in detail using Examples with reference to the drawings, but these Examples are merely illustrative of the present invention, and various modifications may be made within the scope of the present invention. Of course, improvements and variations are possible.
第２図は本発明の太陽電池の−の形態における構成例を
示す。ここで、ｐ（またはｎ）形Ｓｔ単結晶基板１１へ
熱拡散、イオン注入あるいはエピタキシャル成長等によ
りｎ（またはｐ）形Ｓｔ層１２を形成し、これによりＳ
ｔのｐｎ接合１３による下部太陽電池１４を構成する。FIG. 2 shows an example of the configuration of the solar cell of the present invention in the negative form. Here, an n (or p) type St layer 12 is formed on the p (or n) type St single crystal substrate 11 by thermal diffusion, ion implantation, epitaxial growth, etc.
A lower solar cell 14 is constructed by a pn junction 13 of t.
さらに、ｎ（またはｐ）形ＳｉＮ上に膜厚４０〜１００
０人のｎ（またはｐ）形ＧａＡｓ層１５と膜厚４０〜１
０００人のｎ（またはｐ）形成１ｘＧａｌ −χＡ直八
へ組成χ−０，１〜０．９）ｌｉｉ１６の各々２〜７層
を交互に成長させた中間層１７を形成する。第２図では
、ＧａＡｓ１ｉ１５、Ａｌｘ Ｇａｐ −ｘ Ａｓ層１
６の各々３層から成る中間層１７の例を示す。Furthermore, the film thickness is 40 to 100 on n (or p) type SiN.
0 n (or p) type GaAs layer 15 and film thickness 40~1
An intermediate layer 17 is formed by alternately growing 2 to 7 layers of each of the composition χ-0,1 to 0.9)lii16 on the n (or p) layer of 1xGal-χA. In FIG. 2, GaAs1i15, Alx Gap -x As layer 1
An example of an intermediate layer 17 each consisting of three layers in FIG. 6 is shown.
さらに前記ＧａＡｓ層およびＡｌχＧａニーｘＡｓ層（
ただしχ−０，１〜０．９ ） １３の膜厚が４０人未
満であると、旧の拡散を生じ、両膜の区別が生じにくく
なり、また１０００人を超えると、不整合による欠陥、
すなわち結晶転位が生じやす（なる。Further, the GaAs layer and the AlχGa kneexAs layer (
However, if the film thickness of χ-0,1~0.9) 13 is less than 40 layers, old diffusion will occur and it will be difficult to distinguish between the two films, and if it exceeds 1000 layers, defects due to misalignment,
In other words, crystal dislocations are likely to occur.
さらに前記Ａｌｘ Ｇａｌ ＋ ｘ Ａｓ層１３のＡ１
組成は、χ＝０．１から０．９であるが、前記χが０．
１未満であると、ＧａＡｓ層と独立層を形成しにり（、
一方χが０．９を超えると、ＡｌＡｓ層を多く形成し、
酸化しやすく、不安定な層となるとともに、半導体層で
なくなるおそれが生じるからである。Furthermore, A1 of the Alx Gal + x As layer 13
The composition is χ=0.1 to 0.9, but when χ is 0.
When it is less than 1, an independent layer is formed with the GaAs layer (
On the other hand, when χ exceeds 0.9, more AlAs layers are formed,
This is because the layer is easily oxidized and becomes unstable, and there is a risk that the layer will not be a semiconductor layer.
この中間層１７上に、混晶半導体Ａｌｙ Ｇａｐ −ｙ
Ａｓ（’ＡＩ組成Ｏ〜０．４）の不純物を高濃度に添
加したｎ＋（またはｐ”）層１Ｂおよびｐ“（またはｎ
”）層１９によるトンネル接合２０を形成し、このトン
ネル接合２０を介して下部太陽電池１４と上部太陽電池
２１とを接続する。On this intermediate layer 17, a mixed crystal semiconductor Aly Gap -y
The n+ (or p'') layer 1B doped with As ('AI composition O~0.4) impurity and the p'' (or n
") A tunnel junction 20 is formed by the layer 19, and the lower solar cell 14 and the upper solar cell 21 are connected through this tunnel junction 20.
このトンネル接合層２０における混晶半導体ＡｌγＧａ
ｐ−ｙＡｓの組成ｙは０〜０．４であるが、組成ｙが０
．４を超えると、効率を低下させるおそれを生じるから
である。Mixed crystal semiconductor AlγGa in this tunnel junction layer 20
The composition y of p-yAs is 0 to 0.4, but when the composition y is 0
．． This is because if it exceeds 4, there is a risk that the efficiency will decrease.
上部太陽電池２Ｉは、ｐ４（またはｎ” ） Ａｌｙ
Ｇａｓ −ｙ Ａｓ１ｉ１９上にｐ（またはｎ）形Ａ１
ｚＧａ１−ｚＡｓ（＾１組組成 ＝Ｏ〜０．４）層２２
を形成した後ｎ（またはｐ）形Ａｌｚ Ｇａｐ −ｘ
Ａｓ層２３を形成することによりＡｌｘＧａ１−ｘＡｓ
のｐｎ接合２４により構成される。The upper solar cell 2I is p4 (or n”) Aly
p (or n) type A1 on Gas-y As1i19
zGa1-zAs (^1 composition = O~0.4) layer 22
After forming n (or p) type Alz Gap −x
By forming the As layer 23, AlxGa1-xAs
It is composed of a pn junction 24.
前述のように混晶半導体ＡｌＧａＡｓアＡｓの組成２は
０〜０．４であるが、前記組成Ｉが０．４を超えると、
効率が低下するおそれを生じるからである。As mentioned above, the composition 2 of the mixed crystal semiconductor AlGaAs and As is 0 to 0.4, but when the composition I exceeds 0.4,
This is because there is a risk that efficiency will decrease.
次いで、反射防止膜２５および表面層電極２６をｎ（ま
たはｐ）形Ａ１アＧａ１−χＡｓ層２３上に形成し、裏
面電極２７をＳｉ基板１１の裏面に形成することにより
、２個の太陽電池を直列接続した複合接合構造の太陽電
池が構成される。Next, an antireflection film 25 and a surface layer electrode 26 are formed on the n (or p) type A1A Ga1-χAs layer 23, and a back surface electrode 27 is formed on the back surface of the Si substrate 11, thereby forming two solar cells. A solar cell with a composite junction structure is constructed by connecting the two in series.
ｎ（またはｐ）形Ａ１２ Ｇａｌ −ｘ Ａｓ層２３に
おける表面再結合の影響を低減する必要のある場合には
、第２図（Ｂ）に示すように、ｎ（またはｐ）形Ａｌｚ
Ｇａｐ −ｚ Ａｓ層２３の表面にｎ（またはｐ）形
成１ｗ Ｇａ１−ｐｒ Ａｓの組成−＝０．６〜０．９
５から成る窓材料層２８を形成すれば良い。When it is necessary to reduce the influence of surface recombination in the n (or p) type A12 Gal-x As layer 23, as shown in FIG. 2(B), the n (or p) type Alz
Gap -z n (or p) formation on the surface of the As layer 23 1w Ga1-pr Composition of As - = 0.6 to 0.9
What is necessary is to form the window material layer 28 consisting of 5.
前記ＡＩの組成Ｗが０．６未満であると、禁止帯の幅が
少なすぎ、ロスの軽減の作用が行なわれにくく、窓層と
しての機能を発揮しにくいし、また０、９５を超えると
、酸化されやすい不安定な層となり、窓層の機能を発揮
しにくくなるからである。If the composition W of the AI is less than 0.6, the width of the forbidden band is too small, making it difficult to reduce loss and to function as a window layer. This is because the layer becomes unstable and easily oxidized, making it difficult to perform the function of the window layer.
本実施例の太陽電池においては、光電変換効率を高める
ためＳｔとＡｌｚ Ｇａｔ −Ｚ Ａｓの複合接合構造
を用いた。しかし、従来、Ｓｔ基板とＧａＡｓあるいは
ＡｌＧａＡｓとの格子定数の不整合率は４％程度と大き
いことから、Ｓｉ基板上にＧａＡｓあるいはＡｌＧａＡ
ｓ膜を成長させると１０１０ｃｍ−１！以上の高密度の
転位が界面に発生し、ＧａＡｓあるいはＡｌＧａＡｓ膜
中に伝播するため、Ｓｉ基板上へのＧａＡｓＸＡｌＧａ
Ａｓ膜のへテロエピタキシャル成長は難しいとされて来
た。ここで、Ｓｉ基板上に膜厚１０００Å以下のＧａＡ
ｓ膜をヘテロエピタキシャル成長させると、格子不整合
による歪はＧａＡｓエピタキシャル層に含まれ、転位の
発生を回避でき、さらに膜厚１０００Å以下のＡｌｘ
Ｇａｘ −ｘ Ａｓ（ＡＩ組成χ＝０．１〜０．９）と
ＧａＡｓ膜を交互に成長させることにより、格子不整合
による歪を徐々に緩和できることがわかった。これらＧ
ａＡｓ、 ＡｌχＧａニーχＡｓの周期構造を２〜７層
形成することにより、この中間層上に数μｍ程度の膜厚
のＧａＡｓ膜を成長させた場合にもＧａＡｓ膜中の転位
密度はＩＱ’ ｃｍ−２以下たにすることができた。本
発明はかかる効果を利用したもので、ＳｔとＡｌＧａＡ
ｓ定数差に伴う格子歪を緩和するための中間層１７とし
てＧａＡｓ１５とＡｌｘ Ｇａｐ −ｘ Ａｓ１６の同
期構造を用いることにより、良質の＾１ｗ Ｇａ１−ｗ
Ａｓ、 Ａｌｚ Ｇａｐｒ ７ Ａｓ膜の成長が可能
となり、高性能のＡｌｘＧａ１−アＡｓによる上部太陽
電池の作製が可能となった。In the solar cell of this example, a composite junction structure of St and Alz Gat-Z As was used to increase photoelectric conversion efficiency. However, conventionally, the mismatch rate of lattice constants between St substrate and GaAs or AlGaAs is as high as about 4%, so GaAs or AlGaAs is used on Si substrate.
When the s film is grown, it is 1010 cm-1! GaAsXAlGa
It has been said that heteroepitaxial growth of As films is difficult. Here, a GaA film with a thickness of 1000 Å or less is deposited on a Si substrate.
When the S film is grown heteroepitaxially, the strain due to lattice mismatch is contained in the GaAs epitaxial layer, and the generation of dislocations can be avoided.
It has been found that by alternately growing Gax −x As (AI composition χ = 0.1 to 0.9) and GaAs films, the strain caused by lattice mismatch can be gradually alleviated. These G
By forming 2 to 7 layers of a periodic structure of aAs, AlχGa, and χAs, even when a GaAs film with a thickness of several μm is grown on this intermediate layer, the dislocation density in the GaAs film is IQ' cm- I was able to make it less than 2. The present invention utilizes such an effect, and St and AlGaA
By using a synchronous structure of GaAs15 and Alx Gap -x As16 as the intermediate layer 17 to alleviate the lattice strain caused by the difference in s constant, a high-quality ^1w Ga1-w
It has become possible to grow As, Alz Gapr 7 As films, and it has become possible to fabricate a high-performance upper solar cell using AlxGa1-As.
本実施例におけるＳｔのｐｎ接合形成はイオン注入法で
、各層のへテロエピタキシャル成長は分子線エピタキシ
ャル成長法で実施したが、他にＳｉのｐｎ接合形成は熱
拡散法、各種エピタキシャル成長法でも良く、各層のへ
テロエピタキシャル成長も気相エピタキシャル法、液相
エピタキシャル法でも実施できる。In this example, the St pn junction was formed by ion implantation, and the heteroepitaxial growth of each layer was carried out by molecular beam epitaxial growth, but the Si pn junction could also be formed by thermal diffusion or various epitaxial growth methods. Heteroepitaxial growth can also be performed by vapor phase epitaxial method or liquid phase epitaxial method.
また、本実施例の太陽電池においては、上部太陽電池２
１、下部太陽電池１４の積層構造により光電変換効率を
高めている。特に、上部太陽電池２１および下部太陽電
池１４をそれぞれ構成する混晶半導体材料Ａｌｚ Ｇａ
ｔ −ｚ ＡｓおよびＳｉの禁止帯幅が各々１．４３〜
１．９２ｅＶおよびＬ 、 １１ｅＶであり、太陽光に
対するスペクトル感度帯域の拡大がはかられており、光
電変換効率２０％以上が可能となった。本実施例におい
ては、上部太陽電池２１用材料としてＡ１ｚＧａニー２
ＡＳのＡＩ組成χ＝０〜０．４を選んでいるが、さらに
Ａ１組成Ｘ＝０．２〜０．４に混晶半導体材料ＡｌアＧ
ａ１−ｚＡｓの最適化をはかれば、上部太陽電池２１と
下部太陽電池１４との複合接合太陽電池の光電変換効率
は３０％以上が可能である。これにより、本実施例の太
陽電池においては、上太陽電池用混晶半導体材料Ａｌｚ
Ｇａｐ −ｘ ＡｓのＡｔ組成の各々χ＝０〜０．４
、！＝０．２〜０．４のものを用いた場合に、太陽光強
度１００ｍＷ ／ｃｔＡにおける上記太陽電池の重量比
出力も各々１゜３Ｗ／ｇ 、１．９！Ｊ ／ｇと改善さ
れた。さらに、上記太陽電池の作製法を改善すれば、重
量比出力も２．３Ｗ／ｇと従来の太陽電池に比べて数倍
の特性改善が可能である。In addition, in the solar cell of this example, the upper solar cell 2
1. The stacked structure of the lower solar cell 14 increases photoelectric conversion efficiency. In particular, the mixed crystal semiconductor material AlzGa constituting the upper solar cell 21 and the lower solar cell 14, respectively
t −z The forbidden band widths of As and Si are each 1.43~
1.92 eV and L, 11 eV, the spectral sensitivity band to sunlight has been expanded, and a photoelectric conversion efficiency of 20% or more has become possible. In this example, A1zGa knee 2 is used as the material for the upper solar cell 21.
The AS AI composition χ = 0 to 0.4 is selected, but the mixed crystal semiconductor material AlA is further added to the A1 composition X = 0.2 to 0.4.
If a1-zAs is optimized, the photoelectric conversion efficiency of the composite junction solar cell of the upper solar cell 21 and the lower solar cell 14 can be 30% or more. As a result, in the solar cell of this example, the upper solar cell mixed crystal semiconductor material Alz
Gap −x At composition of As, χ = 0 to 0.4
,! = 0.2 to 0.4, the weight specific outputs of the above solar cells at sunlight intensity of 100 mW/ctA are also 1°3 W/g and 1.9! J/g. Furthermore, if the manufacturing method of the solar cell described above is improved, the weight specific output can be improved to 2.3 W/g, which is several times the characteristics of conventional solar cells.
以上説明したように、本発明の太陽電池は、Ｓｉ基板と
混晶半導体ＡｌＧａＡｓとの格子不整合に起因する歪を
緩和するために適した中間層の導入がなされているので
、Ｓｉ基板上に５ｉｐｎ接合から成る下部太陽電池とＡ
ｌアＧａｓ −Ｚ Ａｓｐｎ接合から成る上部太陽電池
との複合接合構造太陽電池が作製でき、なおかつ上部太
陽電池用ＡｌｚＧａｚ−χＡｓの禁止帯幅の最適化がな
され、この複合接合構造により太陽光に対するスペクト
ル感度帯域が拡大されているので光電変換効率が極めて
高く、さらにＳｔ基板の軽量・低価格の特徴も有効に利
用しているので、重量比出力が極めて高いなどの利点を
有する。As explained above, in the solar cell of the present invention, an intermediate layer suitable for alleviating the strain caused by the lattice mismatch between the Si substrate and the mixed crystal semiconductor AlGaAs is introduced. The lower solar cell consisting of 5ipn junction and A
A solar cell with a composite junction structure with an upper solar cell consisting of an AlGas-Z Aspn junction can be fabricated, and the forbidden band width of AlzGaz-χAs for the upper solar cell has been optimized, and this composite junction structure improves the spectrum of sunlight. Since the sensitivity band has been expanded, the photoelectric conversion efficiency is extremely high.Furthermore, since the light weight and low cost characteristics of the St substrate are effectively utilized, it has advantages such as an extremely high output per weight ratio.
第１図は従来の太陽電池の構成例を示す断面図、第２図
（Ａ）および（Ｂ）は本発明の一実施の態様における太
陽電池の構成例を示す断面図である。
■・・・ＧａＡｓ単結晶基板、２・・・ＧａＡｓｐｎ接
合、３・・・下部太陽電池、４・・・＾ｌ Ｇａ Ａｓ
ｐｎ接合、５・・・上部太陽電池、６・・・ＡＩ Ｇ
ａ Ａｓトンネル接合、７・・・ＡＩ Ｇａ Ａｓの窓
層、８・・・反射防止膜、９・・・電極、１１・・・ｐ
（またはｎ）形Ｓｉ単結晶基板、１２・・・ｎ（または
ｐ）形Ｓｔ層、１３・・・５ｉｐｎ接合、１４・・・下
部太陽電池、１５− ｎ（またはｐ）形ＧａＡｓの薄層
、１６・＝ ｎ（またはｐ）形Ａｌｘ Ｇａｐ −ｘ
Ａｓの薄層、１７−ＧａＡｓ −ＡｌｘＧａｘ−χＡｓ
から成る中間層、１８・・・ｎ＋（またはｐ＋）形Ａｌ
ｙ Ｇａｚ −ｙ Ａｓ層、１９・ｐ” （またはｎ＋
）形へＩｙ Ｇａｉ −ｙ Ａｓ層、２０−）ンネル接
合、２１・・・上部太陽電池、２２・・・ｐ（またはｎ
）形＾１アＧａ１−ｘＡｓ層、２３− ｎ（またはｐ）
形Ａ１ｚＧａｚ −ｘＡｓ層、２４−Ａｌ ｚ Ｇａｓ
−ｚ Ａｓ ｐｎ接合、２５・・・反射防止膜、２６
・・・表面電極、２７・・・裏面電極、２８・・・ＡＩ
ｔｖ Ｇａｘ−ｈＡｓの窓層。
出願人代理人 雨 宮 正 季FIG. 1 is a sectional view showing an example of the structure of a conventional solar cell, and FIGS. 2(A) and 2(B) are sectional views showing an example of the structure of a solar cell in an embodiment of the present invention. ■...GaAs single crystal substrate, 2...GaAspn junction, 3...lower solar cell, 4...^l GaAs
pn junction, 5... upper solar cell, 6... AI G
a As tunnel junction, 7... AI Ga As window layer, 8... Antireflection film, 9... Electrode, 11... p
(or n) type Si single crystal substrate, 12...n (or p) type St layer, 13...5ipn junction, 14...lower solar cell, 15- thin layer of n (or p) type GaAs , 16・= n (or p) type Alx Gap −x
Thin layer of As, 17-GaAs-AlxGax-χAs
An intermediate layer consisting of 18...n+ (or p+) type Al
y Gaz −y As layer, 19・p” (or n+
) shape to Iy Gai -y As layer, 20-) tunnel junction, 21... upper solar cell, 22... p (or n
) type^1A Ga1-xAs layer, 23-n (or p)
Type A1zGaz-xAs layer, 24-AlzGas
-z As pn junction, 25... antireflection film, 26
...Surface electrode, 27...Back surface electrode, 28...AI
tv Gax-hAs window layer. Applicant's agent Masaki Amemiya
Claims (2)
上にｐｎ接合を形成して下部太陽電池を構成し、該下部
太陽電池を、各々の膜厚４０〜１０００人のＧａＡｓと
混晶半導体Ａｌｘ Ｇａｌ −ｘ Ａｓ（ＡＩ組成Ｚ
＝０．１〜０．９）の２〜７層を交互に成長させた中間
層および混晶半導体Ａｌｙ Ｇａｐ −ｙ Ａｓ（ＡＩ
組成ｙ ＝０ ”０．４）から成るトンネル接合を介し
て混晶半導体Ａ１ｚＧａ１−ｘ Ａｓ（ＡＩ組成□＝０
〜０．４）から成るｐｎ接合による上部太陽電池と接続
したことを特徴とする太陽電池。(1) Inside the St single crystal substrate or the Si single crystal substrate
A pn junction is formed on the top to constitute a lower solar cell, and the lower solar cell is made of GaAs and a mixed crystal semiconductor Alx Gal -x As (AI composition Z
The intermediate layer and the mixed crystal semiconductor Aly Gap-y As (AI
The mixed crystal semiconductor A1zGa1-x As (AI composition □=0
~0.4) connected to an upper solar cell through a p-n junction.
部太陽電池層上に混晶半導体Ａ１ｗ Ｇａｐ −ｕ Ａ
ｓ（＾１組成−＝０．６〜０．９５）から成る窓層を配
置したことを特徴とする特許請求の範囲第１項記載の太
陽電池。(2) Mixed crystal semiconductor A1w Gap -u A on the upper solar cell layer made of the mixed crystal semiconductor A1χcal-zAs
The solar cell according to claim 1, characterized in that a window layer consisting of s (^1 composition - = 0.6 to 0.95) is disposed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59059219A JPS60201670A (en) | 1984-03-26 | 1984-03-26 | Solar cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59059219A JPS60201670A (en) | 1984-03-26 | 1984-03-26 | Solar cell |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60201670A true JPS60201670A (en) | 1985-10-12 |
Family
ID=13107046
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59059219A Pending JPS60201670A (en) | 1984-03-26 | 1984-03-26 | Solar cell |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60201670A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005057251A (en) * | 2003-07-24 | 2005-03-03 | Kyocera Corp | Multijunction semiconductor element and solar cell element using it |
| US7910916B2 (en) | 2003-06-26 | 2011-03-22 | Kyocera Corporation | Multi-junction type solar cell device |
-
1984
- 1984-03-26 JP JP59059219A patent/JPS60201670A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7910916B2 (en) | 2003-06-26 | 2011-03-22 | Kyocera Corporation | Multi-junction type solar cell device |
| JP2005057251A (en) * | 2003-07-24 | 2005-03-03 | Kyocera Corp | Multijunction semiconductor element and solar cell element using it |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7122733B2 (en) | Multi-junction photovoltaic cell having buffer layers for the growth of single crystal boron compounds | |
| CA1222043A (en) | Solar cells and photodetectors | |
| US6482672B1 (en) | Using a critical composition grading technique to deposit InGaAs epitaxial layers on InP substrates | |
| US7217882B2 (en) | Broad spectrum solar cell | |
| US7309832B2 (en) | Multi-junction solar cell device | |
| CN101859813B (en) | Method for manufacturing quadri-junction GaInP/GaAs/InGaAs/Ge solar cells | |
| US20010018924A1 (en) | Photoelectric converting device | |
| US20140326301A1 (en) | Multijunction photovoltaic device having sige(sn) and (in)gaasnbi cells | |
| US20050081910A1 (en) | High efficiency tandem solar cells on silicon substrates using ultra thin germanium buffer layers | |
| CN100573923C (en) | Silicon base efficient multi-node solar battery and preparation method thereof | |
| CN210535681U (en) | Lattice-mismatched five-junction solar cell | |
| RU2382439C1 (en) | Cascade photoconverter and method of making said photoconverter | |
| CN210272385U (en) | Lattice gradient buffer layer applied to epitaxial growth of lattice-mismatched solar cell | |
| CN109148621B (en) | Double-sided growth efficient six-junction solar cell and preparation method thereof | |
| Wanlass et al. | High-performance, 0.6-eV, Ga 0.32 In 0.68 As/InAs 0.32 P 0.68 thermophotovoltaic converters and monolithically interconnected modules | |
| CN109524492A (en) | A method of it improving multijunction solar cell minority carrier and collects | |
| CN104241416B (en) | Three-junction solar cell with quantum well structure | |
| CN114171615B (en) | Silicon-based multi-junction solar cell and gradual change buffer layer thereof | |
| Katsuyama et al. | New approaches for high efficiency cascade solar cells | |
| JPS60201670A (en) | Solar cell | |
| JPS609178A (en) | Photovoltaic device | |
| Chiang et al. | Large area GaInP/sub 2//GaAs/Ge multijunction solar cells for space applications | |
| WO2003052836A1 (en) | Multi-junction solar cell device | |
| JPS6214110B2 (en) | ||
| Olson et al. | High efficiency, multijunction GaInP/GaAs solar cells |