Process for producing oriented inorganic crystalline film, and semiconductor device using the oriented inorganic crystalline film

1. A process for producing an oriented inorganic crystalline film, comprising the steps of:

(A) forming on a substrate a non-monocrystalline film containing inorganic crystalline particles by a liquid phase technique using a raw-material solution which contains a raw material and an organic solvent, wherein the raw material contains the inorganic crystalline particles and the inorganic crystalline particles have a layered crystal; and

(B) crystallizing said non-monocrystalline film by heating the non-monocrystalline film to a temperature equal to or higher than a crystallization temperature of the non-monocrystalline film so that part of the inorganic crystalline particles act as crystal nuclei.

2. A process according to claim 1 , wherein said part of the inorganic crystalline particles are dispersed in said non-monocrystalline film in said step (A).

3. A process according to claim 1 , wherein said oriented inorganic crystalline film is composed of an oxide and inevitable impurities.

4. A process according to claim 3 , wherein said oxide is a composite oxide expressed by a compositional formula,

N x M y Rz O (x+3y/2+3z/2−d) ,

where R is In, M is at least one of In, Fe, Ga, and Al, N is at least one of Zn and Mg, each of x, y, and z is a real number greater than zero, d indicates an amount of oxygen deficiency, and x, y, z, and d satisfy the relationship,

0 ≦d ≦( x+ 3 y/ 2+3 z/ 2)/10.

5. A process according to claim 1 , wherein said oriented inorganic crystalline film is (00n) orientated, and n is a positive integer.

6. A process according to claim 1 , wherein said inorganic crystalline particles in said part have an average diameter equal to or greater than 2 nm and smaller than a thickness of said non-monocrystalline film.

7. A process according to claim 1 , wherein said inorganic crystalline particles are produced by a sol-gel process using a solution which contains an organic precursor material and an organic solvent, and the organic precursor material contains all constituent elements of said oriented inorganic crystalline film.

8. A process according to claim 1 , wherein said substrate is an amorphous substrate.

9. A process according to claim 8 , wherein said substrate is a resin substrate.

10. A process according to claim 8 , wherein said substrate is a glass substrate.

11. A process according to claim 1 , wherein said non-monocrystalline film is crystallized in said step (B) by heating the non-monocrystalline film with thermic rays.

12. A process according to claim 11 , wherein said thermic rays are pulsed laser rays.