Process for producing semiconductive layers

• US 8,877,657 B2
• Filed: 04/26/2010
• Issued: 11/04/2014
• Est. Priority Date: 04/28/2009
• Status: Expired due to Fees

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Karpov, Andrey, Fleischhaker, Friederike, Domke, Imme, Kastler, Marcel, Wloka, Veronika, Weber, Lothar
• Primary Examiner(s): CHAUDHARI, CHANDRA P
• Application Number:
  US13/266,935
• Publication Number:
  US 20120043537A1
• Time in Patent Office: 1,653 Days
• Field of Search: 257/43, 257/E21.078, 257/E29.094, 438/104, 438/780, 438/781
• US Class Current: 438/781
• CPC Class Codes: C23C 18/1216 Metal oxides C23C18/1212 takes precedence
• CPC Class Codes: C23C 18/1245 Inorganic substrates other than metallic
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02488 Insulating materials
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 27/1292 using liquid deposition, e.g. printing
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

The present invention relates to a process for producing a layer comprising at least one semiconductive metal oxide on a substrate, comprising at least the steps of:

• (A) preparing a solution comprising at least one precursor compound of the at least one metal oxide selected from the group consisting of carboxylates of mono-, di- or polycarboxylic acids having at least three carbon atoms, or derivatives of mono-, di- or polycarboxylic acids, alkoxides, hydroxides, semicarbazides, carbamates, hydroxamates, isocyanates, amidines, amidrazones, urea derivatives, hydroxylamines, oximes, urethanes, ammonia, amines, phosphines, ammonium compounds, azides of the corresponding metal and mixtures thereof, in at least one solvent,
• (B) applying the solution from step (A) to the substrate and
• (C) thermally treating the substrate from step (B) at a temperature of 20 to 200° C., in order to convert the at least one precursor compound to at least one semiconductive metal oxide,
  where, if electrically neutral [(OH)_x(NH₃)_yZn]_z where x, y and z are each independently 0.01 to 10 is used as the precursor compound in step (A), it is obtained by reacting zinc oxide or zinc hydroxide with ammonia, to a substrate which has been coated with at least one semiconductive metal oxide and is obtainable by this process, to the use of this substrate in electronic components, and to a process for preparing electrically neutral [(OH)_x(NH₃)_yZn]_z where x, y and z are each independently 0.01 to 10, by reacting zinc oxide and/or zinc hydroxide with ammonia.

Claims

1. A process for producing a layer comprising zinc oxide on a substrate, the process comprising:

(A) applying a solution comprising

an electrically neutral [(OH)_x(NH₃)_yZn]_z wherein x, y, and z are each independently 0.01 to 10, obtained by reacting at least one of solid zinc oxide and zinc hydroxide with ammonia,

in at least one solvent,

to a substrate; and

(B) thermally treating the substrate from (A) at a temperature of 20 to 200°

C., thereby converting the electrically neutral [(OH)_x(NH₃)_yZn]_zto zinc oxide.

2. The process of claim 1, wherein the substrate is mechanically flexible and comprises at least one plastic.

3. The process of claim 1, wherein the zinc oxide is doped with at least one metal cation selected from the group consisting of Al³⁺, In³⁺, Sn⁴⁺, and Ga³⁺.

4. The process of claim 1, wherein the solution from (A) is applied by at least one operation selected from the group consisting of spin-coating, spray-coating, dip-coating, drop-casting, and printing.

5. A substrate, comprising a coating comprising zinc oxide and obtained by the process of claim 1.

6. An electronic component, comprising the substrate of claim 5.

7. The component of claim 6, which is a TFT, RFID tag, or a display.

8. The process of claim 1, further comprising:

processing to produce a semiconductor component.

9. The process of claim 1, wherein the electrically neutral [(OH)_x(NH₃)_yZn]_z is obtained by reacting solid zinc oxide with ammonia.

10. The process of claim 1, wherein the electrically neutral [(OH)_x(NH₃)_yZn]_z is obtained by reacting solid zinc hydroxide with ammonia.

11. The process of claim 1, wherein x is 2, y is 2 or 4, and z is 1.

12. The process of claim 1, wherein the electrically neutral [(OH)_x(NH₃)_yZn]_z has a purity of 99% or more directly after reacting the solid zinc oxide or the zinc hydroxide with the ammonia, without a further purification.

13. The process of claim 12, wherein the purity is 99.5% or more.

14. The process of claim 12, wherein the purity is 99.9% or more.

15. The process of claim 1, wherein the electrically neutral [(OH)_x(NH₃)_yZn]_z, comprises substantially no Na⁺, K⁺ or NO₃⁻

ions.

16. The process of claim 1, wherein the thermal treating (B) is performed at a temperature of 20 to 50°

C.