Method for vapor-phase growth of thin films of lithium niobate

Claim 2

A PROCESS OF DEPOSITING A FLIM OF LITHIUM NIOBATE ON A SUBSTRATE, SAID SUBSTRATE BEING THERMALLY STABLE UP TO ABOUT 1,000*C, WHICH COMPRISES: A. VAPORIZING A LITHIUM COMPOUND HAVING A VAPOR PRESSURE GREATER THAN 1 MILLIMETER AT A TEMPERATURE OF LESS THAN 500*C AND A STABLE GAS PHASE UP TO 400*C, B. VAPORIZING A NIOBIUM COMPOUND HAVING A VAPOR PRESSURE GREATER THAN 1 MILLIMETER AT A TEMPERATURE OF LESS THAN 500*C AND A STABLE GAS PHASE UP TO 400*C, AND C. CONTACTING SAID SUBSTRATE WITH THE VAPOUR OF SAID LITHIUM COMPOUND AND THE VAPOR OF SAID NIOBIUM COMPOUND IN AN OXIDIZING ATMOPHERE AT A TEMPERATURE OF AT LEAST ABOUT 400*C.

Claim 3

A process according to claim 1 wherein the lithium compound is an organolithium compound.

Claim 4

A process according to claim 2 wherein the organolithium compound is a lithium chelate of a Beta -diketone of the formula

Claim 5

A process according to claim 3 wherein the lithium chelate is the lithium chelate of 2,2,6,6-tetramethyl-3,5-heptanedione.

Claim 6

A process according to claim 1, wherein the niobium compound is an organoniobium compound.

Claim 7

A process according to claim 5 wherein the organoniobium compound is a niobium alkoxide.

Claim 8

A process according to claim 6 wherein the niobium alkoxide is niobium methoxide.

Claim 9

A process according to claim 3 wherein the lithium chelate is vaporized by heating the chelate to a temperature of between about 100* to 300* C.

Claim 10

A process according to claim 6 wherein the niobium alkoxide is vaporized by heating the niobium alkoxide to a tempereature of between about 100* to 300* C.

Claim 11

A process according to claim 1 wherein the substrate is annealed in an oxidizing atmosphere at a temperature of between about 700* to 1,000* C for a period of time of between about 1 to 10 hours after contact with the lithium compound vapor and the niobium compound vapor.

Claim 12

A process according to claim 1 wherein the lithium compound vapor and the niobium compound vapor are transported to the substrate in a stream of an inert carrier gas.

Claim 13

A process according to claim 1 wherein the oxidizing atmosphere is obtained by an oxygen-containing gas.

Claim 14

A process according to claim 1 wherein the process is carried out in an evacuated chamber.

Claim 15

A process of depositing a film of lithium niobate on a substrate, said substrate being thermally stable up to about 1, 000*C, which comprises: a. vaporizing the lithium chelate of 2,2,6,6-tetramethyl-3,5-heptanedione at a temperature of from about 100* to 300* C in a stream of an inert carrier gas, b. vaporizing niobium methoxide at a temperature of from about 100* C to 300* C, c. heating the substrate to a temperature of at least about 400* C, d. contacting the lithium chelate vapor and the niobium methoxide vapor with the substrate in an oxidizing atmosphere so as to deposit a film on the substrate, and e. annealing the substrate and the deposited film at a temperature of about 700* to 1,000* C for a time of about 1 to 10 hours in an oxidizing atmosphere.

Claim 16

A process of depositing a film of lithium niobate on a substrate, said substrate being thermally stable up to about 1, 000*C, which comprises: a. vaporizing the lithium chelate of 2,2,6,6-tetramethyl-3,5-heptanedione at a temperature of from about 100* to 300* C in a stream of an inert carrier gas, b. vaporizing niobium methoxide at a temperature of from about 100* C to 300* C, c. heating the substrate to a temperature of at least about 400* C, d. contacting the lithium chelate vapor and the niobium methoxide vapor with the substrate in an oxidizing atmosphere so as to deposit a film on the substrate, and e. annealing the substrate and the deposited film at a temperature of about 700* to 1,000* C for a time of about 1 to 10 hours in an oxidizing atmosphere.

Claim 17

A process of depositing a film of lithium niobate on a substrate, said substrate being thermally stable up to about 1, 000*C, in an evacuated chamber which comprises: a. vaporizing the lithium chelate of 2,2,6,6-tetramethyl-3,5-heptanedione at a temperature of from about 100* to 300* C, b. vaporizing niobium methoxide at a temperature of from about 100* to 300* C, c. heating the substrate to a temperature of at least 400* C, and d. contacting the substrate with the lithium chelate vapor and the niobium methoxide vapor in an oxidizing atmosphere for about 1 to 20 hours.

Claim 18

A process of depositing a film of lithium niobate on a substrate, said substrate being thermally stable up to about 1, 000*C, in an evacuated chamber which comprises: a. vaporizing the lithium chelate of 2,2,6,6-tetramethyl-3,5-heptanedione at a temperature of from about 100* to 300* C, b. vaporizing niobium methoxide at a temperature of from about 100* to 300* C, c. heating the substrate to a temperature of at least 400* C, and d. contacting the substrate with the lithium chelate vapor and the niobium methoxide vapor in an oxidizing atmosphere for about 1 to 20 hours.