Wafer temperature measuring device with twin structure

Abstract

The invention provides a wafer temperature measuring device of a twin structure, and relates to the technical field of semiconductor wafer detection, and the device comprises a wafer and a detection sub-device connected with the wafer. Wherein the detection sub-device comprises a temperature sensing element, a temperature acquisition processor and a battery, the temperature sensing element is of a twin structure, and a lead of the temperature sensing element is mounted in an etched wire slot in the surface of a wafer and is used for measuring the temperature of the wafer to obtain temperature acquisition data; the temperature acquisition processor is connected with the temperature sensing element and is used for processing the temperature acquisition data to obtain a temperature measurement result; and the battery is connected with the temperature sensing element and the temperature acquisition processor and is used for supplying power to the temperature sensing element and the temperature acquisition processor. According to the invention, the problem that the temperature is difficult to measure accurately during multi-point measurement of the wafer is solved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor wafer detection technology, and in particular to a wafer temperature measurement device with a twin structure. Background Art

[0002] The integrated circuit manufacturing process involves nearly a thousand steps, and processes such as lithography, ion implantation, and vapor deposition all require precise temperature measurement and control. Slight deviations in wafer temperature and temperature non-uniformity above 1% may affect the yield of the final product, so wafer temperature detection technology has been widely used in the integrated circuit manufacturing process.

[0003] At present, wafer temperature detection technology mainly adopts two temperature measurement methods: contact and non-contact. The non-contact temperature measurement method is mainly implemented by optical methods, which is difficult to adapt to the complex environment of integrated circuit manufacturing. Most contact wafer temperature detection technologies directly mount temperature sensors on the surface of the wafer, and then connect the sensors to the external circuit through leads. They are greatly affected by the environment, which affects the measurement accuracy. At the same time, each test point has only one temperature sensor, and self-calibration cannot be achieved. When measuring multiple points of the wafer, the large number of sensor elements leads to complex circuits, which greatly increases the difficulty of wafer temperature measurement. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a wafer temperature measurement device with a twin structure, which solves the problem that it is difficult to accurately measure the temperature of a wafer during multi-point measurement.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is: a wafer temperature measurement device with a twin structure, comprising: a wafer and a detection sub-device connected to the wafer; wherein the detection sub-device comprises a temperature sensing element, a temperature acquisition processor and a battery: The temperature sensing element is a twin structure, and its wires are mounted in the wire grooves etched on the surface of the wafer, and are used to measure the wafer temperature and obtain temperature acquisition data; The temperature acquisition processor is connected to the temperature sensing element and is used to process the temperature acquisition data to obtain a temperature measurement result; The battery is connected to the temperature sensing element and the temperature acquisition processor, and is used to supply power to the temperature sensing element and the temperature acquisition processor.

[0006] The beneficial effects of the present invention are: a wafer temperature measurement device with a twin structure can effectively improve the accuracy of wafer temperature measurement through the layout and processing of temperature sensing elements, collect and process temperature information through a temperature collection and processing circuit, and realize the transmission of temperature information through a Bluetooth module.

[0007] Furthermore, the temperature sensing element is connected to a key point of the temperature acquisition processor for self-calibration and self-verification of the measured wafer temperature; wherein two independent temperature sensing elements are arranged at the key point of the temperature acquisition processor at the same time.

[0008] Furthermore, the depth of the linear grooves etched on the surface of the wafer is 1 / 2 of the thickness of the temperature sensing element, so that the core sensing part of the temperature sensing element is flush with the surface of the wafer.

[0009] In this way, the interference of lead temperature fluctuation on temperature measurement caused by ambient temperature changes can be reduced.

[0010] Furthermore, the temperature sensing element is covered with a heat insulating material.

[0011] In this way, the interference of ambient temperature changes on temperature measurement can be reduced, and the measured temperature can better reflect the temperature conditions inside the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] This specification will be further described in the form of exemplary embodiments, which will be described in detail by the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein: Figure 1 is an exemplary schematic diagram of a wafer temperature measurement device with a twin structure according to some embodiments of this specification; FIG. 2( a ) is an exemplary side view of a wafer body wire slot and a temperature sensing element mounting position according to some embodiments of the present specification; FIG2( b ) is an exemplary top view of a structure in which a temperature sensing element is covered with a heat insulating material according to some embodiments of the present specification; FIG. 3( a ) is an exemplary side view of a structure in which a temperature sensing element is covered with a heat insulating material according to some embodiments of the present specification; FIG3( b ) is an exemplary top view of a structure in which a temperature sensing element is covered with a heat insulating material according to some embodiments of the present specification; Figure 4 is an exemplary schematic diagram of a layout of a twin temperature sensing element according to some embodiments of this specification; Figure 5 It is an exemplary schematic diagram of the distribution of multi-channel twin temperature measurement wafer test points according to some embodiments of this specification. DETAILED DESCRIPTION

[0013] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0014] Example Figure 1 is an exemplary schematic diagram of a wafer temperature measurement device with a twin structure according to some embodiments of this specification.

[0015] In some embodiments, the twin-structure wafer temperature measurement device may include a wafer and a detection sub-device connected to the wafer; wherein the detection sub-device includes a temperature sensing element, a temperature acquisition processor and a battery: the temperature sensing element is a twin structure, and its wires are mounted in wire grooves etched on the surface of the wafer, for measuring the wafer temperature and obtaining temperature acquisition data; the temperature acquisition processor is connected to the temperature sensing element, for processing the temperature acquisition data and obtaining a temperature measurement result; the battery is connected to the temperature sensing element and the temperature acquisition processor, for powering the temperature sensing element and the temperature acquisition processor.

[0016] The wafer is a standard wafer with line grooves etched on the surface.

[0017] In some embodiments, the wafer body can be pre-grooved by dry etching, wet etching, laser grooving, or the like to obtain surface etched line grooves.

[0018] The detection sub-device is a device for detecting the temperature of the wafer. For example, the detection sub-device may include a temperature sensing element, a temperature acquisition processor, and a battery.

[0019] In some embodiments, the detection sub-device can be a circuit structure, which can be manufactured using mature printed circuit board technology and can be a rigid circuit board or a flexible circuit board; wherein the detection circuit can use a FR4 board with a thickness of 0.5 mm, and more preferably, the detection circuit is a flexible circuit board made of polyimide.

[0020] In some embodiments, the detection circuit can adopt a hollow structure, and temperature sensor element solder joints are provided on the outer edge and internal hollow area of ​​the circuit board. The temperature sensor elements are evenly distributed on the wafer body, and the temperature sensor elements are bonded to the wafer body in the working state.

[0021] In this way, good contact between the temperature sensing element and the wafer body can be achieved.

[0022] The temperature sensing element is a twin structure, and its wires are mounted in the wire grooves etched on the surface of the wafer to measure the wafer temperature and obtain temperature acquisition data. For example, the temperature sensing element can include thermocouples, thermistors, platinum resistors, and integrated temperature sensor chips.

[0023] The temperature acquisition data is data reflecting the temperature of the wafer after correction.

[0024] The temperature acquisition processor is connected to the temperature sensor element to process the temperature acquisition data and obtain the temperature measurement result. For example, the core area of ​​the temperature acquisition processor may include a main control chip, a voltage regulator chip, a Bluetooth module, a Bluetooth antenna, and a thin film battery.

[0025] The temperature acquisition processor can be used to collect and transmit the temperature information of the sensor element.

[0026] The temperature measurement result reflects the wafer temperature result after being measured by the detection sub-device.

[0027] In some embodiments, as shown in FIG. 2( a ) and FIG. 2( b ), one or more temperature sensing elements are electrically connected to the temperature acquisition processor, and in a working state, the wires of the temperature sensing elements are bonded to the wafer.

[0028] In some embodiments, the temperature acquisition processor can be used to realize the temperature information acquisition and transmission of the sensor element.

[0029] In some embodiments, the temperature sensing element is connected to a key point of the temperature acquisition processor for self-calibration and self-verification of the measured wafer temperature; wherein two independent temperature sensing elements are arranged at the key point of the temperature acquisition processor at the same time.

[0030] In some embodiments, solder joints of temperature sensing elements are reserved at the edge of the temperature acquisition processor, and are set as serial twin temperature sensor points at key points.

[0031] The battery is connected to the temperature sensing element and the temperature acquisition processor and is used to supply power to the temperature sensing element and the temperature acquisition processor.

[0032] In some embodiments, the depth of the line grooves etched on the wafer surface is 1 / 2 of the thickness of the temperature sensing element, so that the core sensing part of the temperature sensing element is flush with the wafer surface.

[0033] In this way, the interference of lead temperature fluctuation on temperature measurement caused by ambient temperature changes can be reduced.

[0034] In some embodiments, as shown in FIG. 3( a ) and FIG. 3( b ), the temperature sensing element is covered with a heat insulating material.

[0035] The heat insulating material is a material used to maintain the temperature collected by the temperature sensing element. For example, the heat insulating material may include materials such as polyethylene and polyurethane and shapes such as rectangular parallelepiped, hemispherical, cylindrical, etc.

[0036] In this way, the interference of ambient temperature changes on temperature measurement can be reduced, and the measured temperature can better reflect the temperature conditions inside the wafer.

[0037] In some embodiments, Figure 4 As shown, the temperature sensing elements at the key points or all points of wafer temperature measurement can be arranged in a twin structure.

[0038] In some embodiments, Figure 5 As shown, a 63-point test is adopted, with key points marked as "★", and a twin structure is used for layout; when one or even several temperature sensors in a certain area fail, other non-failed temperature sensors will not be affected and provide information independently. The system can obtain the accurate temperature of each temperature zone based on the information provided by the non-failed sensors, and use the redundancy and complementarity of multiple temperature sensor information to verify the validity of the sensor outputs, and combine the outputs of each temperature sensor to measure the wafer temperature.

[0039] In this way, self-calibration and self-verification of the sensing element can be achieved, improving the measurement accuracy of the temperature measuring wafer.

[0040] In some embodiments of the present specification, a twin-structure wafer temperature measurement device can effectively improve the accuracy of wafer temperature measurement through the layout and processing of temperature sensing elements, collect and process temperature information through a temperature collection and processing circuit, and realize the transmission of temperature information through a Bluetooth module.

[0041] The above describes the specific implementation methods of the present invention. The present invention is not limited to the above specific implementation methods. Those skilled in the art may make various modifications within the scope of the claims without affecting the essential content of the present invention.

Claims

1. A wafer temperature measurement device with a twin structure, characterized in that: include: A wafer and a detection sub-device connected to the wafer; wherein the detection sub-device includes a temperature sensing element, a temperature acquisition processor and a battery: The temperature sensing element is a twin structure, and its wires are mounted in the wire grooves etched on the surface of the wafer, and are used to measure the wafer temperature and obtain temperature acquisition data; The temperature acquisition processor is connected to the temperature sensing element and is used to process the temperature acquisition data to obtain a temperature measurement result; The battery is connected to the temperature sensing element and the temperature acquisition processor, and is used to supply power to the temperature sensing element and the temperature acquisition processor.

2. The wafer temperature measurement device of the twin structure according to claim 1, characterized in that: The temperature sensing element is connected to the key point of the temperature acquisition processor and is used for self-calibration and self-verification of the measured wafer temperature; wherein two independent temperature sensing elements are arranged at the key point of the temperature acquisition processor at the same time.

3. The wafer temperature measurement device of the twin structure according to claim 1, characterized in that: The depth of the grooves etched on the wafer surface is 1 / 2 of the thickness of the temperature sensing element, so that the core sensing part of the temperature sensing element is flush with the wafer surface.

4. The wafer temperature measurement device of the twin structure according to claim 1, characterized in that: The temperature sensing element is covered with a heat insulating material.

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