# US 10,373,838 B2 · Automatic sampling of hot phosphoric acid for the determination of chemical element concentrations and control of semiconductor processes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,373,838 B2 - Document ID: US10373838B2 - Status: Granted - Kind: B2 - Application number: 15/366,250 - Filed: 2016-12-01 - Published: 2017-06-08 - Granted: 2019-08-06 - Earliest claimed: 2015-12-08 - Assignees: Elemental Scientific, Inc. - Applicants: Elemental Scientific, Inc. - Inventors: Kyle W. Uhlmeyer; Jae Seok Lee; Daniel R. Wiederin; Patrick Sullivan - Web page: https://patentgrep.com/patent/US10373838B2 ## CPC - H10P 50/642: {Chemical etching} - G01N 1/2035: {by deviating part of a fluid stream, e.g. by drawing-off or tapping} - G01N 35/1097: {characterised by the valves (valves in general F16K)} - G01N 2001/1062: {Sampling under constant temperature, pressure, or the like} - G01N 2001/2057: {Sample chamber in a valve/piston} - H10P 50/283: {by chemical means} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract Systems and methods for automatic sampling of a sample for the determination of chemical element concentrations and control of semiconductor processes are described. A system embodiment includes a remote sampling system configured to collect a sample of phosphoric acid at a first location, the remote sampling system including a remote valve having a holding loop coupled thereto; and an analysis system configured for positioning at a second location remote from the first location, the analysis system coupled to the remote valve via a transfer line, the analysis system including an analysis device configured to determine a concentration of one or more components of the sample of phosphoric acid and including a sample pump at the second location configured to introduce the sample from the holding loop into the transfer line for analysis by the analysis device. ## Claims ### Claim 1 A system comprising: a remote sampling system configured to collect a sample of phosphoric acid at a first location, the sample of phosphoric acid collected at the first location being at least about 150 degree, the remote sampling system including a remote valve having a holding loop coupled thereto through which the sample of phosphoric acid is configured to selectably flow; and an analysis system configured for positioning at a second location remote from the first location, the analysis system coupled to the remote valve via a transfer line, the analysis system including an analysis device configured to determine a concentration of one or more components of the sample of phosphoric acid and including a sample pump at the second location configured to introduce the sample from the holding loop into the transfer line for analysis by the analysis device. ### Claim 2 (depends on 1) The system of claim 1, wherein the sample of phosphoric acid has a temperature from about 150° C. to about 180° C. at the first location. ### Claim 3 (depends on 1) The system of claim 1, wherein the analysis system further includes a local sample valve coupled to the remote valve via the transfer line and coupled to the analysis device. ### Claim 4 (depends on 1) The system of claim 1, further comprising: a thermal sheath surrounding at least a portion of the transfer line. ### Claim 5 (depends on 4) The system of claim 4, wherein the thermal sheath includes a temperature-regulated fluid in an annular region between the thermal sheath and the transfer line. ### Claim 6 (depends on 1) The system of claim 1, wherein the analysis system includes at least one of a carrier pump coupled to the remote valve via a carrier fluid line, a diluent pump coupled to the remote valve via a diluent fluid line, or a standard pump coupled to the remote valve via a standard fluid line. ### Claim 7 (depends on 6) The system of claim 6, further comprising: a thermal sheath surrounding at least a portion of the transfer line and at least one of the carrier fluid line, the diluent fluid line, or the standard fluid line. ### Claim 8 (depends on 7) The system of claim 7, wherein the thermal sheath includes a temperature-regulated fluid in an annular region between the thermal sheath and the transfer line. ### Claim 9 (depends on 7) The system of claim 7, wherein the at least one of the carrier fluid line, the diluent fluid line, or the standard fluid line is positioned in an annular region between the thermal sheath and the transfer line. ### Claim 10 (depends on 1) The system of claim 1, further including a communicative coupling, the communicative coupling configured to provide a control signal between the analysis system and one or more of a heater of a phosphoric acid etching system at the first location, a recirculation pump configured to recirculate phosphoric acid of the phosphoric acid etching system, or a pump configured to introduce fresh phosphoric acid to the phosphoric acid etching system. ### Claim 11 (depends on 10) The system of claim 10, wherein the control signal is based on the concentration of one or more components of the sample of phosphoric acid determined by the analysis system. ### Claim 12 (depends on 10) The system of claim 10, wherein the control signal is configured to maintain a silicon concentration in the phosphoric acid etching system within about 50 ppm. ### Claim 13 A method, comprising: receiving a sample of phosphoric acid at a first location with a remote sampling system, the phosphoric acid received at the first location being at least about 150 degree; introducing the sample of phosphoric acid into a holding loop of the remote sampling system via operation of a pump positioned at a second location remote from the first location or a local sample pump positioned at the first location; introducing at least one of a carrier fluid, a diluent fluid, or a standard fluid to the sample of phosphoric acid at the remote sampling system; transferring the sample of phosphoric acid from the remote sampling system through a transfer line to the second location via operation of a second pump positioned at the second location; and determining a concentration of a chemical element in the sample of phosphoric acid via an analysis device at the second location. ### Claim 14 (depends on 13) The method of claim 13, wherein the sample of phosphoric acid has a temperature from about 150° C. to about 180° C. at the first location. ### Claim 15 (depends on 13) The method of claim 13, further comprising: controlling a temperature of the sample of phosphoric acid during the step of transferring the sample of phosphoric acid from the remote sampling system through the transfer line to the second location via operation of the second pump positioned at the second location. ### Claim 16 (depends on 15) The method of claim 15, wherein controlling a temperature of the sample of phosphoric acid includes transferring the sample of phosphoric acid from the remote sampling system through the transfer line, wherein the transfer line is positioned concentrically within a thermal sheath. ### Claim 17 (depends on 16) The method of claim 16, wherein at least one of a carrier fluid line, a diluent fluid line, or a standard fluid line is positioned in a region between the transfer line and the thermal sheath. ### Claim 18 (depends on 15) The method of claim 15, wherein controlling the temperature of the sample of phosphoric acid during the step of transferring the sample of phosphoric acid includes at least one of cooling the sample of phosphoric acid to, or maintaining the sample of phosphoric acid at, a temperature from about 30° C. to about 100° C. ### Claim 19 (depends on 13) The method of claim 13, further comprising: providing a control signal to one or more of a heater of a phosphoric acid etching system at the first location, a recirculation pump configured to recirculate phosphoric acid of the phosphoric acid etching system, or a pump configured to introduce fresh phosphoric acid to the phosphoric acid etching system, the control signal based on the concentration of the chemical element in the sample of phosphoric acid determined via the analysis device at the second location. ### Claim 20 (depends on 19) The method of claim 19, wherein the control signal is configured to maintain a silicon concentration in the phosphoric acid etching system within about 50 ppm.