# US 2016/0257593 A1 · Manufacturing process for striae-free multicomponent chalcogenide glasses via multiple fining steps > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0257593 A1 - Document ID: US20160257593A1 - Status: Published application - Kind: A1 - Application number: 15/059,637 - Filed: 2016-03-03 - Published: 2016-09-08 - Earliest claimed: 2015-03-03 - Assignees: The Government of the United of America, as represented by the Secretary of the Navy - Applicants: The Government of the United of America, as represented by the Secretary of the Navy - Inventors: Vinh Q. Nguyen; Mikhail Kotov; Daniel J. Gibson; Shyam S. Bayya; Jasbinder S. Sanghera; Gryphon A. Drake - Web page: https://patentgrep.com/patent/US20160257593A1 ## CPC - C03C 3/321: {Chalcogenide glasses, e.g. containing S, Se, Te} - C03B 1/00: Preparing the batches (chemical compositions C03C) - C03B 5/06: in pot furnaces {(C03B5/02 takes precedence)} - C03B 5/16: Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces - C03B 5/187: with moving elements - C03B 25/00: Annealing glass products - C03B 27/028: {the liquid being water-based} - C03B 2201/86: Chalcogenide glasses, i.e. S, Se or Te glasses - C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS - C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES ## Abstract The present invention provides a method for synthesizing high optical quality multicomponent chalcogenide glasses without refractive index perturbations due to striae, phase separation or crystal formation using a two-zone furnace and multiple fining steps. The top and bottom zones are initially heated to the same temperature, and then a temperature gradient is created between the top zone and the bottom zone. The fining and cooling phase is divided into multiple steps with multiple temperature holds. ## Claims ### Claim 1 A method to make striae-free chalcogenide glass, comprising: loading chalcogenide glass precursors into an ampoule, sealing the ampoule, and placing the ampoule in a rocking furnace, wherein the rocking furnace comprises a top zone and a bottom zone, wherein the top and bottom zones are two independently controllable temperature zones; heating both the top and bottom zones at a rate of 3° C. per minute to a Step 1 temperature, wherein the Step 1 temperature is the same for both the top and bottom zones; maintaining the Step 1 temperature in the top and bottom zones while rocking the furnace at an inclination angle of ±45° for about 15 hours; increasing the temperature of the top zone at a rate of 3° C. per minute to a Step 3 top zone temperature and decreasing the temperature of the bottom zone at a rate of 3° C. per minute to a Step 3 bottom zone temperature while rocking the furnace at an inclination angle of ±45°, wherein there is a temperature gradient of 100° C. between the Step 3 top zone temperature and the Step 3 bottom zone temperature; setting the furnace to a vertical position and maintaining the Step 3 top zone temperature and the Step 3 bottom zone temperature for about 3 hours; decreasing the temperature of the top zone at a rate of 10° C. per minute to a Step 5 top zone temperature, decreasing the temperature of the bottom zone at a rate of 10° C. per minute to a Step 5 bottom zone temperature, and maintaining the Step 5 top zone temperature and Step 5 bottom zone temperature for about 3 hours, wherein the Step 5 top zone temperature is about 100° C. lower than the Step 3 top zone temperature, and wherein the Step 5 bottom zone temperature is about 100° C. lower than the Step 3 bottom zone temperature; decreasing the temperature of the top zone at a rate of 10° C. per minute to a Step 6 top zone temperature, decreasing the temperature of the bottom zone at a rate of 10° C. per minute to a Step 6 bottom zone temperature, and maintaining the Step 6 top zone temperature and Step 6 bottom zone temperature for about 3 hours, wherein the Step 6 top zone temperature is about 100° C. lower than the Step 5 top zone temperature, and wherein the Step 6 bottom zone temperature is about 100° C. lower than the Step 5 bottom zone temperature; decreasing the temperature of the top zone at a rate of 10° C. per minute to a Step 7 top zone temperature, decreasing the temperature of the bottom zone at a rate of 10° C. per minute to a Step 7 bottom zone temperature, and maintaining the Step 7 top zone temperature and Step 7 bottom zone temperature for about 30 minutes, wherein the Step 7 top zone temperature is at least 100° C. lower than the Step 6 top zone temperature, and wherein the Step 7 bottom zone temperature is at least 100° C. lower than the Step 6 bottom zone temperature; and removing the ampoule from the furnace and water quenching the glass. ### Claim 2 (depends on 1) The method of claim 1, wherein the chalcogenide glass precursors comprise germanium, arsenic, sulfur, and selenium. ### Claim 3 (depends on 1) The method of claim 1, wherein the chalcogenide glass precursors are sufficient to constitute a glass with the composition of x % at. germanium, y % at. arsenic, z % at. selenium, and (100-x-y-z) % at. sulfur, wherein 0≦x≦10, 30≦x+y≦45, and 0≦z≦10. ### Claim 4 (depends on 1) The method of claim 1, wherein the chalcogenide glass precursors are sufficient to constitute a glass with the composition of x % at. germanium, y % at. arsenic, z % at. selenium, and (100-x-y-z) % at. sulfur, wherein 0≦x≦25, 30≦x+y≦55, and 0≦z≦20. ### Claim 5 (depends on 1) The method of claim 1, wherein the Step 1 temperature is about 680° C. ### Claim 6 (depends on 1) The method of claim 1, wherein the Step 1 temperature is about 650° C. ### Claim 7 (depends on 1) The method of claim 1, wherein the Step 3 top zone temperature is about 750° C. and the Step 3 bottom zone temperature is about 650° C. ### Claim 8 (depends on 1) The method of claim 1, wherein the Step 7 top zone temperature is about 450° C. and the Step 7 bottom zone temperature is about 350° C. ### Claim 9 (depends on 1) The method of claim 1, wherein the Step 7 top zone temperature is about 300° C. and the Step 7 bottom zone temperature is about 200° C. ### Claim 10 A striae-free chalcogenide glass made by the method, comprising: loading chalcogenide glass precursors into an ampoule, sealing the ampoule, and placing the ampoule in a rocking furnace, wherein the rocking furnace comprises a top zone and a bottom zone, wherein the top and bottom zones are two independently controllable temperature zones; heating both the top and bottom zones at a rate of 3° C. per minute to a Step 1 temperature, wherein the Step 1 temperature is the same for both the top and bottom zones; maintaining the Step 1 temperature in the top and bottom zones while rocking the furnace at an inclination angle of ±45° for about 15 hours; increasing the temperature of the top zone at a rate of 3° C. per minute to a Step 3 top zone temperature and decreasing the temperature of the bottom zone at a rate of 3° C. per minute to a Step 3 bottom zone temperature while rocking the furnace at an inclination angle of ±45°, wherein there is a temperature gradient of 100° C. between the Step 3 top zone temperature and the Step 3 bottom zone temperature; setting the furnace to a vertical position and maintaining the Step 3 top zone temperature and the Step 3 bottom zone temperature for about 3 hours; decreasing the temperature of the top zone at a rate of 10° C. per minute to a Step 5 top zone temperature, decreasing the temperature of the bottom zone at a rate of 10° C. per minute to a Step 5 bottom zone temperature, and maintaining the Step 5 top zone temperature and Step 5 bottom zone temperature for about 3 hours, wherein the Step 5 top zone temperature is about 100° C. lower than the Step 3 top zone temperature, and wherein the Step 5 bottom zone temperature is about 100° C. lower than the Step 3 bottom zone temperature; decreasing the temperature of the top zone at a rate of 10° C. per minute to a Step 6 top zone temperature, decreasing the temperature of the bottom zone at a rate of 10° C. per minute to a Step 6 bottom zone temperature, and maintaining the Step 6 top zone temperature and Step 6 bottom zone temperature for about 3 hours, wherein the Step 6 top zone temperature is about 100° C. lower than the Step 5 top zone temperature, and wherein the Step 6 bottom zone temperature is about 100° C. lower than the Step 5 bottom zone temperature; decreasing the temperature of the top zone at a rate of 10° C. per minute to a Step 7 top zone temperature, decreasing the temperature of the bottom zone at a rate of 10° C. per minute to a Step 7 bottom zone temperature, and maintaining the Step 7 top zone temperature and Step 7 bottom zone temperature for about 30 minutes, wherein the Step 7 top zone temperature is at least 100° C. lower than the Step 6 top zone temperature, and wherein the Step 7 bottom zone temperature is at least 100° C. lower than the Step 6 bottom zone temperature; and removing the ampoule from the furnace and water quenching the glass. ### Claim 11 (depends on 10) The chalcogenide glass of claim 10, wherein the chalcogenide glass precursors comprise germanium, arsenic, sulfur, and selenium. ### Claim 12 (depends on 10) The chalcogenide glass of claim 10, wherein the chalcogenide glass precursors are sufficient to constitute a glass with the composition of x % at. germanium, y % at. arsenic, z % at. selenium, and (100-x-y-z) % at. sulfur, wherein 0≦x≦10, 30≦x+y≦45, and 0≦z≦10. ### Claim 13 (depends on 10) The chalcogenide glass of claim 10, wherein the chalcogenide glass precursors are sufficient to constitute a glass with the composition of x % at. germanium, y % at. arsenic, z % at. selenium, and (100-x-y-z) % at. sulfur, wherein 0≦x≦25, 30≦x+y≦55, and 0≦z≦20. ### Claim 14 (depends on 10) The chalcogenide glass of claim 10, wherein the Step 1 temperature is about 680° C. ### Claim 15 (depends on 10) The chalcogenide glass of claim 10, wherein the Step 1 temperature is about 650° C. ### Claim 16 (depends on 10) The chalcogenide glass of claim 10, wherein the Step 3 top zone temperature is about 750° C. and the Step 3 bottom zone temperature is about 650° C. ### Claim 17 (depends on 10) The chalcogenide glass of claim 10, wherein the Step 7 top zone temperature is about 450° C. and the Step 7 bottom zone temperature is about 350° C. ### Claim 18 (depends on 10) The chalcogenide glass of claim 10, wherein the Step 7 top zone temperature is about 300° C. and the Step 7 bottom zone temperature is about 200° C.