Aluminum precursor and process for the generation of metal-containing films

Abstract

The present disclosure is in the field of processes for the generation of thin inorganic films on substrates, in particular atomic layer deposition processes. Described herein is a process for preparing metal-containing films including: (a) depositing a metal-containing compound from the gaseous state onto a solid substrate, and (b) bringing the solid substrate with the deposited metal-containing compound in contact with a compound of general formula (I) ##STR00001## wherein Z is a C.sub.2-C.sub.4 alkylene group, and R is hydrogen, an alkyl group, an alkenyl group, an aryl group, or a silyl group.

Claims

1. Process for preparing metal-containing films, the process comprising: (a) depositing a metal-containing compound from a gaseous state onto a solid substrate, and (b) bringing the solid substrate with the deposited metal-containing compound in contact with a compound of general formula (I) ##STR00005## wherein Z is a C.sub.2-C.sub.4 alkylene group, and R is hydrogen, an alkyl group, an alkenyl group, an aryl group, or a silyl group.

2. The process according to claim 1, wherein R comprises no hydrogen atom in the 1-position.

3. The process according to claim 2, wherein R is tert-butyl.

4. The process according to claim 1, wherein Z is ethylene.

5. The process according to claim 1, wherein the compound of general formula (I) has a molecular weight of not more than 600 g/mol.

6. The process according to claim 1, wherein the compound of general formula (I) has a vapor pressure of at least 1 mbar at a temperature of 200° C.

7. The process according to claim 1, wherein (a) and (b) are successively performed at least twice.

8. The process according to claim 1, wherein the metal-containing compound contains Ti, Ta, Mn, Mo, W, or Al.

9. The process according to claim 1, wherein the metal-containing compound is a metal halide.

10. The process according to claim 1, wherein a temperature does not exceed 350° C.

11. A compound of general formula (I), ##STR00006## wherein Z is a C.sub.2-C.sub.4 alkylene group, and R is hydrogen, an alkyl group, an alkenyl group, an aryl group, or a silyl group.

12. The compound according to claim 11, wherein R comprises no hydrogen atom in the 1-position.

13. The compound according to claim 12, wherein R is tert-butyl.

14. The compound according to claim 11, wherein Z is ethylene.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows the thermogravimetry (TG) and the differential thermogravimetry (DTG) curves of compound I-1.

(2) FIG. 2 shows the vapor pressure (P) dependence on the temperature (T) of compound I-1.

(3) FIG. 3 shows the crystal structure of compound C-1 as obtained from single crystal X-ray diffraction analysis.

(4) FIG. 4 shows the grazing incidence X-ray diffractogram (GIXRD) for examples 2 and 3.

EXAMPLES

Example 1: Synthesis of I-1

(5) ##STR00004##

(6) N—N′-di-tert-butyl imidazolidene-2-yl was heated with 2 equivalents of AlH.sub.3(NMe.sub.3) in refluxing toluene until evolution of NMe.sub.3 ceased after about 30 min. Evaporation of the solvent allowed isolation of C-1 in 82% yield.

(7) The thermogravimetry curve is shown in FIG. 1. The weight loss at 200° C. is 76.6%, at 500° C. it is 95.3%. Vapor pressure measurements are shown in FIG. 2, wherein the triangles, squares and crosses represent results of different measurements and the solid line is a line fit for the results below 150° C.

(8) Crystals suitable for X-ray diffraction analysis were grown from a concentrated toluene solution at −20° C. The crystal structure is shown in FIG. 3.

Example 2: Al Film Deposition on TiN

(9) A TiN substrate was kept at 140° C. in an ALD apparatus. A supply of AlCl.sub.3 was kept at 95° C., a separate supply for compound I-1 was kept at 100° C. 300 cycles were performed, wherein one cycle was: 2 s AlCl.sub.3, 20 s nitrogen purge, 3 s compound I-1, 10 s nitrogen purge.

Example 3: Al Film Deposition on Cu

(10) Example 2 was repeated, but instead of TiN, a Cu substrate was used.

(11) FIG. 4 shows the grazing incidence X-ray diffractogram (GIXRD) measured under an angle of 1° for both samples obtained in examples 2 and 3. Reflections matching Al metal are indicated in the diffractogram.