CN-121978873-A - Gas bath device with distributed temperature control function for photoetching machine equipment

CN121978873ACN 121978873 ACN121978873 ACN 121978873ACN-121978873-A

Abstract

The invention discloses an air bath device with a distributed temperature control function for photoetching equipment, and belongs to the technical field of photoetching. The technical problems that the temperature control precision is attenuated, the dynamic thermal disturbance of the sensor cannot be restrained, and the real-time closed-loop regulation and control capability of the tail end is lacking in long-distance conveying are solved. The temperature control layer in the device takes a ceramic substrate as a carrier, a plurality of thermoelectric refrigerators and temperature sensors are alternately attached to the working surface of the device, and the back surface of the device dissipates heat through a liquid cooling plate. The uniform air supply assembly ensures that a parallel uniform laminar flow is output. The thermoelectric refrigeration controller dynamically drives the corresponding thermoelectric refrigerators to refrigerate or heat by one-to-one or one-to-many independent control loops according to real-time temperature field data fed back by the temperature sensor, so that local temperature fine adjustment with high spatial resolution and high dynamic response is realized. The invention can directly compensate long-distance conveying temperature drift, actively inhibit local thermal disturbance caused by optical components, and realize the spanning from 'preset air supply' to 'terminal active temperature control'.

Inventors

Hu Peilu
ZHAO NANNAN
XUE FEI
FU JINGYUAN

Assignees

浙江启尔机电技术有限公司

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (10)

1. A gas bath device with a distributed temperature control function for photoetching equipment is characterized by comprising a cavity, a high-efficiency air filter, a temperature control layer, a uniform air supply assembly, an external constant-temperature water circulation system and a thermoelectric refrigeration controller; the cavity is an air supply pipeline channel, an efficient air filter is arranged at the inlet of the cavity, and a uniform air supply assembly is arranged at the outlet of the cavity; a temperature control layer is arranged on the leeward side of the cavity body, and comprises a liquid cooling plate, a plurality of thermoelectric refrigerators, a ceramic substrate and a plurality of temperature sensors; the ceramic substrate is characterized in that one surface of the ceramic substrate facing the air flow is a ceramic substrate working surface, a plurality of thermoelectric coolers and a plurality of temperature sensors are distributed on the ceramic substrate working surface, one side of the ceramic substrate facing away from the air flow is a radiating surface which is connected with a liquid cooling plate, the thermoelectric coolers realize refrigeration or heating through current regulation under the driving of a thermoelectric refrigeration controller and the feedback of the temperature sensors so as to control the temperature of outlet air flow, the liquid cooling plate is connected to an external constant temperature water circulation system through an internal pipeline, and the external constant temperature water circulation system and the liquid cooling plate work cooperatively to maintain the temperature stability of the radiating surface of the ceramic substrate; When the temperature sensor is used, each temperature sensor and one or a group of thermoelectric refrigerators corresponding to the temperature sensor form an independent control loop to realize independent temperature closed-loop adjustment of different areas of the temperature control layer, after air flow enters from the cavity, the air flow sequentially passes through the high-efficiency air filter and the temperature control layer, and finally, the uniform air flow component is used for measuring the surface of the sensor in the photoetching machine with high precision to form a closed air flow which flows uniformly, has stable temperature and is isolated from the external environment.
2. The gas bath device with distributed temperature control function for a photo-etching machine device according to claim 1, wherein the thermoelectric refrigerators and the temperature sensors are mounted on the working surface of the ceramic substrate in a staggered manner, a two-dimensional matrix distribution form is adopted for a uniform flow field area, fitting arrangement is carried out on vortex gas flow traces, and distribution density is improved for a critical flow field area of a gas bath in a light path area so as to improve control accuracy.
3. The gas bath device with distributed temperature control function for a lithographic apparatus according to claim 1, wherein the ceramic substrate is an integrated high thermal conductivity insulating ceramic substrate, and the working surface of the ceramic substrate forms a power supply circuit by a precision printing and sintering process, and is used as a circuit connection among a thermoelectric cooler, a temperature sensor and a thermoelectric cooling controller.
4. The gas bath apparatus with distributed temperature control function for a lithographic apparatus according to claim 1, wherein the plurality of thermoelectric coolers and the plurality of temperature sensors are attached to the ceramic substrate by a highly thermally conductive material.
5. The gas bath device with the distributed temperature control function for the photoetching machine equipment according to claim 1, wherein the uniform air supply assembly comprises a filter cloth, a porous plate and a grid which are sequentially arranged, and the air flow after temperature regulation is filtered by the filter cloth and then is guided to the surface of the high-precision measuring sensor by the porous plate and the grid.
6. The gas bath device with distributed temperature control function for a lithographic apparatus according to claim 1, wherein the porous plate is a plate with an array of uniformly distributed circular holes, providing a stable gas flow for a high-precision measuring sensor in a region directly below the gas bath device, and the grating is a honeycomb grating structure, providing a stable gas flow for a high-precision measuring sensor in a lateral region of the gas bath device.
7. The gas bath device with distributed temperature control function for a lithographic apparatus according to claim 1, wherein the liquid cooling plate adopts a three-dimensional micro-channel structure with optimized thermal topology.
8. A gas bath apparatus with distributed temperature control function for a lithographic apparatus according to claim 1, The specific process of the closed-loop temperature regulation is as follows: Firstly, setting a target temperature, continuously collecting data by a temperature sensor at high frequency, generating a two-dimensional temperature field reflecting real-time temperature distribution of the whole working surface after signal processing, and calculating the deviation between the actual temperature of each position and the target temperature by an upper computer, and recording the deviation as an error; the thermoelectric refrigeration controller processes the error signal generated by comparing the actual temperature with the target temperature through a control algorithm to generate a control instruction to drive the thermoelectric refrigerator to perform heating or refrigeration operation.
9. A gas bath apparatus with distributed temperature control function for a lithographic apparatus according to claim 1, When the local air flow temperature is higher than a set value, a thermoelectric refrigeration controller firstly positions a specific sensor partition with the temperature exceeding the standard, then drives one or a group of thermoelectric refrigerators corresponding to the partition and the adjacent region to apply refrigeration current, and starts a refrigeration mode, wherein the cold end of the thermoelectric refrigerator facing the air flow starts to actively absorb heat of air flowing through the surface of the thermoelectric refrigerator; When the temperature of the local air flow is lower than a set value, a thermoelectric refrigeration controller firstly positions a specific sensor partition with too low temperature, then drives one or a group of thermoelectric refrigerators corresponding to the partition and the adjacent region, applies thermoelectric current, and starts a heating mode, and in order to maintain the heating process, the thermoelectric refrigerators absorb heat from a back liquid cooling plate, pump the heat to the front end to release the heat through a Peltier effect pump, and at the moment, the liquid cooling plate and an external constant temperature water circulation system cooperatively provide a stable low-temperature heat source for the thermoelectric refrigerators.
10. A lithographic apparatus comprising a gas bath device with distributed temperature control according to any one of claims 1 to 9, wherein the gas bath device locally gas-bathes at least one of the light path area of the interferometer, the readhead of the planar grating ruler and its light path area, the wafer surface micro-environment area carried by the stage.

Description

Gas bath device with distributed temperature control function for photoetching machine equipment Technical Field The invention relates to the technical field of design lithography, in particular to an air bath device with a distributed temperature control function, which is used for guaranteeing the stability of a local microenvironment of a lithography machine. Technical Field In integrated circuit manufacturing, the overlay accuracy of a lithography machine is one of the core performance indexes for determining the interlayer alignment quality of chip patterns, and the stability of the overlay accuracy is directly dependent on the measurement accuracy of high-accuracy measurement sensors such as interferometers. The sensor has extremely high requirements on the thermal stability of the local environment, even extremely small temperature fluctuation can cause the sensor to generate micrometer or even nanometer measurement drift, further directly influence the superposition accuracy of an exposure pattern and finally threaten the overall performance and yield of the chip. Currently, a mainstream photoetching machine generally adopts a high-precision gas bath system, and a controlled local microenvironment is created for a high-precision measurement sensor in the photoetching machine so as to maintain the stability of the ambient temperature, pressure and cleanliness of the photoetching machine. The general working flow of the system is that clean and dry air processed by an ultra-high precision temperature control unit is conveyed to an air bath plate above a sensor through a heat preservation air pipe. The inside of the air bath plate is designed with a flow equalizing hole or a micro-channel structure, so that the air flow is uniformly and stably covered on the surface of the high-precision measuring sensor, and an air curtain isolating external disturbance is formed, thereby realizing the thermal management of the working environment of the sensor. The prior art has the following defects: Firstly, the temperature control precision in the long-distance conveying process is attenuated. When reaching the end of the gas bath through a delivery pipe of several meters, the gas source with high temperature stability exchanges heat with the pipe wall and is affected by heat radiation and convection from the external environment. The passive transmission process inevitably leads to gas temperature drift, the stability of the gas is obviously reduced compared with that of the gas source outlet, and the high-precision temperature control effect of the front end is difficult to be transmitted to a key area of the sensor in a lossless manner. Secondly, the device does not have a distributed temperature control function, can not adjust local air flow or compensate heat, and lacks active inhibition capability on local dynamic heat disturbance. The sensor itself can generate non-uniform, time-varying heat dissipation during operation, creating an unpredictable localized heat source. The traditional gas bath system is used as a passive flow equalizing device, the temperature and the flow speed of the gas flow are usually fixed, the change of the heat distribution on the surface of the sensor cannot be perceived in real time, and the capability of carrying out local gas flow adjustment or heat compensation on the dynamic heat disturbance is not provided, so that the local temperature field of the sensor fluctuates. Third, the system lacks a closed loop feedback regulation mechanism based on the end temperature. The existing scheme is mainly open-loop control, and airflow parameters are directly supplied to the use points after being uniformly set at the front end. The whole conveying and distributing link lacks real-time monitoring and feedback of the actual temperature of the near end of the sensor, the system cannot sense the temperature drift introduced in the transmission process and cannot respond to the local heat accumulation caused by the heating of the sensor, so that real-time dynamic correction and environmental stability in the real sense are difficult to realize. Therefore, there is a need for an air bath device that can actively control the temperature of the microenvironment surrounding a high-precision measurement sensor. Disclosure of Invention The invention aims to provide an air bath device with a distributed temperature control function, which is fixedly arranged on a main body frame of a whole machine of a photoetching machine, wherein an outlet of the air bath device faces to a local area (such as a workpiece table area, a mask table area and the like) of a high-precision measuring sensor arranged in the photoetching machine, clean gas is guided by an air supply assembly such as filter cloth, a porous plate, a grid and the like, an air flow layer isolated from the outside is formed on the surface of the high-precision measuring sensor of the photoetching machine, and meanwhile, the distributed temper