Ink composition for manufacturing light absorption layer including metal nano particles and method of manufacturing thin film using the same

Abstract

Disclosed are an ink composition for manufacturing a light absorption layer including metal nano particles and a method of manufacturing a thin film using the same, more particularly, an ink composition for manufacturing a light absorption layer including copper (Cu)-enriched CuIn bimetallic metal nano particles and Group IIIA metal particles including S or Se dispersed in a solvent and a method of manufacturing a thin film using the same.

Claims

1. An ink composition for manufacturing a light absorption layer comprising: a solvent consisting of a mixture of alcohol-based solvents; nano particles dispersed in the solvent, wherein the only nano particles present in the ink composition consist of: 1) Cu.sub.2In bimetallic metal nano particles and In.sub.2S.sub.3 nano particles; 2) Cu.sub.2In bimetallic metal nano particles, In.sub.2S.sub.3 nano particles, and Ga.sub.2Se.sub.3 nano particles; 3) Cu.sub.2In bimetallic metal nano particles and InGaS.sub.3 nano particles; or 4) Cu.sub.2In bimetallic metal nano particles and In.sub.2Se.sub.3 nano particles, and wherein a ratio of Cu to (In+Ga) in the ink composition is between 0.5 and 1.5.

2. The ink composition according to claim 1, wherein a ratio of an amount of S and Se to an amount of In and Ga (n/m) is 0.5<(n/m)3.

3. The ink composition according to claim 1, wherein the solvent is at least one organic solvent selected from the group consisting of alkanes, alkenes, alkynes, aromatics, ketons, nitriles, ethers, esters, organic halides, alcohols, amines, thiols, carboxylic acids, phosphines, phosphates, sulfoxides, and amides.

4. The ink composition according to claim 1, wherein the ink composition further comprises an additive.

5. The ink composition according to claim 4, wherein the additive is at least one selected from the group consisting of polyvinylpyrrolidone (PVP), Polyvinylalcohol, and ethyl cellulose.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawing, in which:

(2) FIG. 1 is a phase diagram of CuIn;

(3) FIG. 2 is a scanning electron microscope (SEM) image of Cu.sub.2In nano particles formed according to Example 17;

(4) FIG. 3 is an X-ray diffraction (XRD) graph of Cu.sub.2In nano particles formed according to Example 17;

(5) FIG. 4 is a scanning electron microscope (SEM) image of In.sub.2S.sub.3 nano particles manufactured according to Example 19;

(6) FIG. 5 is a scanning electron microscope (SEM) image of In.sub.2Se.sub.3 nano particles manufactured according to Example 21;

(7) FIG. 6 is an X-ray diffraction (XRD) graph of In.sub.2Se.sub.3 nano particles manufactured according to Example 21;

(8) FIG. 7 is a scanning electron microscope (SEM) image of Ga.sub.2Se.sub.3 nano particles manufactured according to Example 22;

(9) FIG. 8 is an X-ray diffraction (XRD) graph of Ga.sub.2Se.sub.3 nano particles manufactured according to Example 22;

(10) FIG. 9 is a scanning electron microscope (SEM) image of InGaS.sub.3 nano particles manufactured according to Example 23;

(11) FIG. 10 is a scanning electron microscope (SEM) image of InGaSe.sub.3 nano particles manufactured according to Example 24;

(12) FIG. 11 is an X-ray diffraction (XRD) graph of CuIn nano particles manufactured according to Comparative Example 1;

(13) FIG. 12 is an X-ray diffraction (XRD) graph of a sample of ink according to Example 28 dried at 180 C.;

(14) FIG. 13 is an X-ray diffraction (XRD) graph of a sample dried at 180 C. after coating ink according to Comparative Example 5;

(15) FIG. 14 is an SEM image of a thin film manufactured according to Example 31;

(16) FIG. 15 is an XRD graph of a thin film manufactured according to Example 31;

(17) FIG. 16 is an SEM image of a thin film manufactured according to Comparative Example 6;

(18) FIG. 17 is an XRD graph of a thin film manufactured according to Comparative Example 6; and

(19) FIG. 18 is a graph showing IV characteristics of a thin film solar cell manufactured according to Example 40.

BEST MODE

(20) Now, the present invention will be described in more detail with reference to the following examples. These examples are provided only for illustration of the present invention and should not be construed as limiting the scope and spirit of the present invention.

Example 1

Synthesis Cu2In Particles

(21) 20 mmol of CuSO.sub.4*5H.sub.2O and 10 mmol of InCl.sub.3 were dissolved in 50 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 2

Synthesis of Cu2In Particles

(22) 20 mmol of CuSO.sub.4*5H.sub.2O and 10 mmol of InCl.sub.3 were dissolved in 200 ml of DMF to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of DMF and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 3

Synthesis of Cu2In Particles

(23) 20 mmol of CuSO.sub.4*5H.sub.2O and 10 mmol of InCl.sub.3 were dissolved in 200 ml of DMSO to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 150 ml of DMSO and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 4

Synthesis on Particles

(24) 20 mmol of Cu(NO.sub.3).sub.2*2.5H.sub.2O and 10 mmol of InCl.sub.3 were dissolved in 200 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered by using centrifugation. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles

Example 5

Synthesis of Cu2In Particles

(25) 30 mmol of sodium tartrate, 20 mmol of CuSO.sub.4*5H.sub.2O and 10 mmol of InCl.sub.3 were sequentially dissolved in 100 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 200 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 6

Synthesis of Cu2In Particles

(26) 60 mmol of sodium tartrate, 20 mmol of Cu(NO.sub.3)*2.5H.sub.2O and 10 mmol of InCl.sub.3 were sequentially dissolved in 150 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 300 mmol of NaBH.sub.4 was dissolved in 150 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 7

Synthesis of Cu2In Particles

(27) 40 mmol of sodium tartrate, 20 mmol of CuSO.sub.4*2H.sub.2O and 10 mmol of In(NO.sub.3).sub.3 were sequentially distilled in 80 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 80 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 8

Synthesis of Cu2In Particles

(28) 30 mmol of sodium tartrate, 20 mmol of CuSO.sub.4*5H.sub.2O and 10 mmol of In(Cl.sub.3).sub.3 were sequentially dissolved in 100 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 600 mmol of NaBH.sub.4 was dissolved in 200 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 9

Synthesis of Cu2In Particles

(29) 30 mmol of sodium tartrate, 20 mmol of CuCl.sub.2*2H.sub.2O and 10 mmol of In(Cl.sub.3).sub.3 were sequentially dissolved in 50 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 50 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 10

Synthesis Cu2In Particles

(30) 0.1 g of PVP, 20 mmol of CuCl.sub.2*2H.sub.2O and 10 mmol of InCl.sub.3 were sequentially dissolved in 60 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 150 mmol of NaBH.sub.4 was dissolved in 80 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 11

Synthesis of Cu2In Particles

(31) 30 mmol of sodium citrate tribasic, 20 mmol of CuCl.sub.2*2H.sub.2O, 10 mmol of InCl.sub.3 were sequentially dissolved in 50 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 50 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 12

Synthesis of Cu2In Particles

(32) 20 mmol of CuCl.sub.2*2H.sub.2O, 10 mmol of InCl.sub.3 were sequentially dissolved in 100 ml of DMSO to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of DMSO and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 13

Synthesis of Cu2In Particles

(33) 20 mmol of CuCl.sub.2*2H.sub.2O, 10 mmol of InCl.sub.3 were sequentially dissolved in 100 ml of DMSO to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 14

Synthesis of Cu11In9 Particles

(34) 11 mmol of CuCl.sub.2*2H.sub.2O, 9 mmol of InCl.sub.3 were sequentially dissolved in 100 ml of DMSO to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of DMSO. Under nitrogen atmosphere, temperature was set to 100 C. and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 15

Synthesis of Cu11In9 Particles

(35) 11 mmol of CuCl.sub.2*2H.sub.2O, 9 mmol of InCl.sub.3 were sequentially dissolved in 100 ml of NMP to prepare a mixture. Under nitrogen atmosphere, 150 mmol of NaBH.sub.4 was dissolved in 100 ml of NMP, temperature was set to 100 C., and the above mixture was added dropwise for 1 hour, sequentially. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 16

Synthesis of Cu2In Particles

(36) 30 mmol of sodium citrate tribasic, 20 mmol of Cu(NO.sub.3).sub.2*2.5H.sub.2O, 10 mmol of InCl.sub.3 were sequentially dissolved in 100 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 100 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles.

Example 17

Synthesis of Cu2In Particles

(37) 20 mmol of CuCl.sub.2*2H.sub.2O and 10 mmol of InCl.sub.3 were sequentially dissolved in 50 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 200 mmol of NaBH.sub.4 was dissolved in 50 ml of distilled water and then the above mixture was added dropwise for 1 hour. This mixture was stirred for 1 day and then filtered using vacuum filtration. The filtered mixture was purified with distilled water, resulting in Cu.sub.2In metal nano particles. An SEM-EDX image and XRD graph of the formed particles are shown in FIGS. 2 and 3.

Example 18

Synthesis of Cu2In Particles

(38) 10 mmol of CuCl.sub.2*2H.sub.2O and 5 mmol of InCl.sub.3 were slowly added to 150 mmol of a NaBH.sub.4 solution in which 100 ml of an isopropanol solution was dissolved in 100 ml of a triethylene glycol solution, and then were stirred for 3 hours. After terminating the reaction, Cu.sub.2In metal nano particles were obtained by purifying using centrifugation.

Example 19

Synthesis of In2S3

(39) 10 mmol of InCl.sub.3 dissolved in 50 ml of distilled water was added to 15 mmol of sodium sulfide nonahydrate dissolved in 100 ml of distilled water and then the mixture was stirred for 1 day. Thereafter, the stirred mixture was purified using centrifugation, resulting in a bright yellow particles in which a ratio of In to S is 2 to 3. An electron microscope (SEM-EDX) image of the formed particles is shown in FIG. 4.

Example 20

Synthesis of In2Se3

(40) Under nitrogen atmosphere, 2.37 g of NaBH.sub.4 was dissolved in 200 ml of distilled water and then 2.37 g of Se powder was added thereto. After stirring for 20 minutes, 20 mmol of InCl.sub.3 dissolved in 100 ml of distilled water was added thereto and then stirred for 5 hours. The stirred mixture was centrifuged, resulting in In.sub.2Se.sub.3 particles.

Example 21

Synthesis of In2Se3

(41) Under nitrogen atmosphere, 10 mmol of NaBH.sub.4 was dissolved in 20 ml of distilled water, 5 mmol of H.sub.2SeO.sub.3, instead of Se particles used in the above example, was dissolved in 10 ml of distilled water, and the H.sub.2SeO.sub.3 solution was added dropwise to the NaBH.sub.4 solution, sequentially. The resulting solution was stirred for 20 minutes and then 3.3 mmol of an InCl.sub.3 solution dissolved in 10 ml of distilled water was added thereto. The resulting solution was stirred for 3 hours and then centrifuged, resulting in In.sub.2Se.sub.3 particles having a size of less than 50 nm. These In.sub.2Se.sub.3 particles were thermal treated for 15 minutes at 350 C. under nitrogen atmosphere, resulting in approximately 100 nm particles having an In.sub.2Se.sub.3 crystal structure. An SEM-EDX image and XRD graph of the finally formed particles are shown in FIGS. 5 and 6.

Example 22

Synthesis of Ga2Se3

(42) Under nitrogen atmosphere, 31.2 mmol of NaBH.sub.4 was dissolved in 80 ml of distilled water and then 15 mmol of Se powder was added thereto. This mixture was stirred until a clear solution is formed and then 10 mmol of GaI.sub.3 dissolved in 60 ml of distilled water was slowly added thereto. The resulting solution was stirred overnight and then was purified using centrifugation, resulting in a Ga.sub.2Se.sub.3 composition having 10 to 20 nm particles. The Ga.sub.2Se.sub.3 composition was thermal treated, resulting in a Ga.sub.2Se.sub.3 crystal structure. An SEM-EDX image and XRD graph of the formed particles are shown in FIGS. 7 and 8.

Example 23

Synthesis of InGaS3 Particles

(43) Under nitrogen atmosphere, 30 mmol of Na.sub.2S*9H.sub.2O was dissolved in 100 ml of distilled water and then a mixture in which 10 mmol of InCl.sub.3 and GaI.sub.3 10 mmol dissolved in 100 ml of distilled water was slowly added thereto. The resulting solution was stirred overnight and then centrifuged and vacuum-dried, resulting in InGaS.sub.3 particles having a size of 10 to 20 nm. Here, the InGaS.sub.3 particles were analyzed using ICP. An electron microscope (SEM-EDX) image of the formed particles is shown in FIG. 9.

Example 24

Synthesis of InGaSe3

(44) Under nitrogen atmosphere, 60 mmol of NaBH.sub.4 was dissolved in 100 ml of distilled water and then 30 mmol of a H.sub.2SeO.sub.3 solution dissolved in 60 ml of distilled water was added dropwise thereto. After formation of a colorless and transparent solution, a mixture in which 10 mmol of InCl.sub.3 and GaI.sub.3 10 mmol were dissolved in 100 ml of distilled water was slowly added slowly to the solution. The resulting solution was stirred overnight and then centrifuged and vacuum-dried, resulting in InGaSe.sub.3 particles having a size of 1020 nm. An electron microscope (SEM-EDX) image of the formed particles was shown in FIG. 10.

Example 25

Synthesis of InSe

(45) 20 mmol of a H.sub.2SeO.sub.3 solution dissolved in 300 ml of ethylene glycol was inserted into a flask and then 20 ml of a 1.0 M In nitrate aqueous solution was added thereto. This resulting mixture was reacted 150 C. for 6 hours. Particles formed through the reaction were purified using centrifugation in which ethanol is used, resulting in InSe particles.

Example 26

Synthesis of In0.7Ga0.3Se

(46) 20 mmol of H.sub.2SeO.sub.3 in dissolved 300 ml of ethylene glycol was inserted into a flask and then 14 ml of a 1.0 M In nitrate aqueous solution and 6 ml of 1.0 M Ga nitrate aqueous solution were added thereto. This resulting mixture was reacted at 150 C. for 6 hours and then obtained particles were purified using centrifugation in which ethanol is used, resulting in In.sub.0.7Ga.sub.0.3Se particles.

Example 27

Synthesis of In0.5Ga0.5Se

(47) 20 mmol of H.sub.2SeO.sub.3 in dissolved 300 ml of ethylene glycol was inserted into a flask and then 10 ml of a 1.0 M In nitrate aqueous solution and 10 ml of 1.0 M Ga nitrate aqueous solution were added thereto. This resulting mixture was reacted at 150 C. for 6 hours and then obtained particles were purified using centrifugation in which ethanol is used, resulting in In.sub.0.5Ga.sub.0.5Se particles.

Comparative Example 1

(48) 30 mmol of a NaBH.sub.4 solution dissolved in 100 ml of a triethylene glycol solution was slowly added to 10 mmol of InCl.sub.3 and 10 mmol of PVP in dissolved in 150 ml of an isopropanol solution and then stirred for 10 minutes. To this mixture, 10 mmol of a CuCl.sub.2 solution dissolved in 50 ml of an isopropanol solution and 20 mmol of a NaBH.sub.4 solution dissolved in 50 ml of triethylene glycol together were added dropwise and then was further stirred for 10 minutes. The resulting solution was purified using centrifugation, resulting in nano particles having a CuIn, Cu.sub.2In and CuIn.sub.2 structure. An XRD graph analyzing of the formed particles is shown in FIG. 11.

Comparative Example 2

(49) 20 mmol of a sodium citrate trisodium salt, 10 mmol of CuCl.sub.2*2H.sub.2O and 10 mmol of InCl.sub.3 were sequentially dissolved in 180 ml of distilled water to prepare a mixture. Under nitrogen atmosphere, 600 mmol of NaBH.sub.4 was dissolved in 360 ml of distilled water and then the above mixture was added dropwise for 1 hour thereto. The resulting solution was stirred for 1 day and then filtered using vacuum filtration and purified with distilled water. As a result, CuIn nano particles in which a ratio of Cu to In is 1 to 1 were obtained in a yield ratio of 98%.

Comparative Example 3

(50) 10 mmol of CuCl.sub.2 and 10 mmol of InCl.sub.3 were dissolved in 100 ml of distilled water. This solution was added dropwise to 60 mmol of a NaBH.sub.4 solution dissolved in 200 ml of distilled water and then stirred for 1 hour, resulting in nano particles having a CuIn, Cu.sub.2In and CuIn.sub.2 structure.

Comparative Example 4

(51) 20 mmol of a sodium tartrate solution in dissolved in 30 ml of distilled water and 150 mmol of a NaBH.sub.4 solution dissolved in 70 ml of distilled water were mixed and then 10 mmol of CuCl.sub.2*2H.sub.2O and 10 mmol of InCl.sub.3 in dissolved in 50 ml of distilled water were added dropwise thereto for 3 hours. The reacted solution was purified using centrifugation and then vacuum-dried, resulting in nano particles having a CuIn, Cu.sub.2In, CuIn.sub.2 structure.

Example 28

(52) To manufacture ink, the Cu.sub.2In nano particles according to Example 17 and the In.sub.2Se.sub.3 nano particles according to Example 20 were dispersed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 24% such that a ratio of Cu/In was 0.97. The resulting solution was dried up to 180 C. and then analyzed using XRD. As result, a In.sub.2O.sub.3 structure confirmed in FIG. 12 was not observed.

Comparative Example 5

(53) CuIn nano particles, in which a ratio of Cu/In is 1.0, synthesized according to Comparative Example 2 were dispersed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 25%. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then analyzed using XRD. Analysis results are shown in FIG. 13. As a result, it is confirmed that, when CuIn is changed to a Cu-enriched Cu.sub.11In.sub.9 structure, In ions are released and the released In ions are oxidized, resulting in generation of an In.sub.2O.sub.3 crystal structure.

Example 29

Manufacture of Thin Film

(54) To manufacture ink, the Cu.sub.2In nano particles according to Example 17 and the In.sub.2S.sub.3 nano particles according to Example 19 were mixed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 24% such that a ratio of Cu/In was 0.96. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated at 250 C. for 5 minutes and at 530 C. for 5 minutes under Se atmosphere, resulting in a CI(G)S thin film.

Example 30

Manufacture of Thin Film

(55) To manufacture ink, the Cu.sub.2In nano particles according to Example 13, the In.sub.2S.sub.3 nano particles according to Example 19 and Ga.sub.2Se.sub.3 nano particles according to Example 22 were mixed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 19% such that a ratio of Cu/(In+Ga) was 0.96 and a ratio of Ga/In was 0.19. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated twice at 530 C. for 5 minutes under Se atmosphere, resulting in a CI(G)S thin film.

Example 31

Manufacture of Thin Film

(56) To manufacture ink, the Cu.sub.2In nano particles according to Example 17 and InGaS.sub.3 nano particles according to Example 23 were mixed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 19% such that a ratio of Cu/(In+Ga) was 0.96 and a ratio of Ga/In was 0.25. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated sequentially at 530 for 5 minutes and 575 C. for 5 minutes under Se atmosphere, resulting in a CI(G)S thin film. A sectional view and XRD graph of such an obtained thin film are shown in FIGS. 14 and 15.

Example 32

Manufacture of Thin Film

(57) To manufacture ink, the Cu.sub.2In nano particles according to Example 17 and In.sub.2Se.sub.3 nano particles according to Example 20 were mixed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 25% such that a ratio of Cu/In was 0.95. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated at 530 C. for 5 minutes under Se atmosphere, resulting in a CI(G)S thin film.

Example 33

Manufacture of Thin Film

(58) To manufacture ink, the Cu.sub.2In nano particles according to Example 4 and In.sub.2Se.sub.3 nano particles according to Example 20 were mixed in a solvent consisting of a mixture of alcohol-based solvents and amine-based solvents in a concentration of 25% such that a ratio of Cu/In was 0.95. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated at 550 C. under Se atmosphere, resulting in a CI(G)S thin film.

Example 34

Manufacture of Thin Film

(59) To manufacture ink, the Cu.sub.2In nano particles according to Example 17 and In.sub.2Se.sub.3 nano particles according to Example 19 were mixed in a solvent consisting of a mixture of alcohol-based solvents and amine-based solvents in a concentration of 24% such that a ratio of Cu/In was 0.97. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated twice at 530 C. for 5 minutes under Se atmosphere, resulting in a CI(G)S thin film.

Comparative Example 6

Manufacture of Thin Film

(60) To manufacture ink, CuIn nano particles, in which a ratio of Cu/In is 1.0, synthesized according to Comparative Example 2 were dispersed in a solvent consisting of a mixture of alcohol-based solvents in a concentration of 25%. Such manufactured ink was coated on a substrate obtained by depositing Mo on a glass substrate, resulting in a coating layer for manufacturing a CI(G)S thin film. The resulting coating layer was dried up to 180 C. and then thermal treated twice at 530 C. under Se atmosphere, resulting in a CI(G)S thin film. A sectional view and XRD graph of such an obtained thin film are shown in FIGS. 16 and 17.

Example 35