# US 10,307,884 B2 · Apparatus for controlling a movement of a grinding wheel, semiconductor wafer grinding system and method for forming semiconductor devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,884 B2 - Document ID: US10307884B2 - Status: Granted - Kind: B2 - Application number: 15/655,477 - Filed: 2017-07-20 - Published: 2018-01-25 - Granted: 2019-06-04 - Earliest claimed: 2016-07-21 - Assignees: Infineon Technologies AG - Applicants: Infineon Technologies AG - Inventors: Rudolf Lehner - Web page: https://patentgrep.com/patent/US10307884B2 ## CPC - B24B 49/16: taking regard of the load - B24B 49/006: {taking regard of the speed} - B24B 51/00: Arrangements for automatic control of a series of individual steps in grinding a workpiece (if applicable to other machine tools, G05B takes precedence) - H10D 48/01: Manufacture or treatment - H10D 62/8325: {Silicon carbide} - H10D 84/035: {using silicon carbide [SiC] technology} - H10P 52/00: Grinding, lapping or polishing of wafers, substrates or parts of devices - H10P 54/00: Cutting or separating of wafers, substrates or parts of devices - H10P 72/0428: {Apparatus for mechanical treatment or grinding or cutting} - H10P 72/0604: {Process monitoring, e.g. flow or thickness monitoring} - H10P 72/74: {using temporarily an auxiliary support} - H10P 95/60: Mechanical treatments, e.g. by ultrasounds - H10P 72/7416: {used during dicing or grinding} - B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract An apparatus for controlling a movement of a grinding wheel of a semiconductor wafer grinding system includes: an interface to obtain a feedback signal including grinding force information indicating a force applied to a semiconductor wafer by the grinding wheel; and a control module to generate a control signal for controlling the movement of the grinding wheel based on the grinding force information. The control module generates the control signal to trigger a forward movement of the grinding wheel according to a desired velocity profile during the grinding, if the grinding force information indicates that a force applied by the grinding wheel is below a force threshold. The control module generates the control signal to trigger a movement of the grinding wheel slower than the desired velocity profile during the grinding, if the grinding force information indicates that the force applied by the grinding wheel is above the force threshold. ## Claims ### Claim 1 An apparatus for controlling a movement of a grinding wheel of a semiconductor wafer grinding system, the apparatus comprising: at least one interface configured to obtain a feedback signal comprising grinding force information indicating a force applied to a semiconductor wafer by the grinding wheel; and a control module configured to generate a control signal for controlling the movement of the grinding wheel based on the grinding force information, wherein the control module is configured to generate the control signal to trigger a forward movement of the grinding wheel according to a desired velocity profile during grinding of the semiconductor wafer if the grinding force information indicates that a force applied by the grinding wheel is below a force threshold, wherein the control module is configured to generate the control signal to trigger a movement of the grinding wheel slower than the desired velocity profile during grinding of the semiconductor wafer if the grinding force information indicates that the force applied by the grinding wheel is above the force threshold, and wherein the at least one interface is configured to provide the control signal for controlling the movement of the grinding wheel. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the control module is configured to generate the control signal to trigger a backward movement during grinding of the semiconductor wafer if the grinding force information indicates that the force applied by the grinding wheel remains above the force threshold after slowing. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the desired velocity profile is based on a target semiconductor wafer thickness. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the desired velocity profile comprises a first portion with a velocity above an average profile velocity for a coarse grinding towards the target semiconductor wafer thickness and a second portion with a velocity below an average profile velocity for a fine grinding towards the target semiconductor wafer thickness. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the velocity for the coarse grinding is at least 50% higher than the velocity for the fine grinding. ### Claim 6 (depends on 4) The apparatus of claim 4, wherein the target semiconductor wafer thickness is smaller than 200 μm. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the control module is configured to generate the control signal to trigger a backward movement of the grinding wheel after a target semiconductor wafer thickness is reached. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the control module is configured to generate the control signal to trigger a polishing of the semiconductor wafer with the grinding wheel during the backward movement. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein a velocity of the backward movement during polishing is slower than 50% of an average velocity of the desired velocity profile during grinding. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the grinding force information comprises information related to a motor current of a motor driving the grinding wheel. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the grinding force information comprises information related to a pressure exerted from the grinding wheel to the semiconductor wafer. ### Claim 12 A semiconductor wafer grinding system, comprising: a wafer carrier structure configured to hold a semiconductor wafer; a grinding wheel for grinding the semiconductor wafer; at least one interface configured to obtain a feedback signal comprising grinding force information indicating a force applied to the semiconductor wafer by the grinding wheel; and a control module configured to generate a control signal for controlling movement of the grinding wheel based on the grinding force information, wherein the grinding wheel comprises a grinding material structure comprising a plurality of grinding stones embedded in a bonding material, wherein at least 80% of the grinding stones of the plurality of grinding stones have a diameter of more than 25 μm and the plurality of grinding stones occupy more than 40% of the grinding material structure, wherein the control module is configured to generate the control signal to trigger a forward movement of the grinding wheel according to a desired velocity profile during grinding of the semiconductor wafer if the grinding force information indicates that a force applied by the grinding wheel is below a force threshold, wherein the control module is configured to generate the control signal to trigger a movement of the grinding wheel slower than the desired velocity profile during grinding of the semiconductor wafer if the grinding force information indicates that the force applied by the grinding wheel is above the force threshold, wherein the at least one interface is configured to provide the control signal for controlling a movement of the grinding wheel. ### Claim 13 (depends on 12) The semiconductor wafer grinding system of claim 12, wherein the at least 80% of the grinding stones of the plurality of grinding stones have a diameter of less than 125 μm. ### Claim 14 (depends on 12) The semiconductor wafer grinding system of claim 12, wherein the grinding stones of the plurality of grinding stones comprise at least one of diamond, silicon carbide and corundum.