US-12628606-B2 - Laser beam adjustment in semiconductor device fabrication

US12628606B2US 12628606 B2US12628606 B2US 12628606B2US-12628606-B2

Abstract

An intensity of a power laser beam applied to a semiconductor device is adjusted. An applied intensity of the power laser beam is indicative of a magnitude at which the power laser beam is emitted toward the semiconductor device and a reflection intensity of a probing laser beam applied to the semiconductor device is indicative of an emissivity of the semiconductor device. The reflection intensity of the probing laser beam is measured to determine the emissivity of the semiconductor device and the applied intensity of the power laser beam is adjusted as a function of the emissivity.

Inventors

Wei-Fu Wang
Yi-Chao Wang
Li-Ting Wang
Yee-Chia Yeo

Assignees

TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LIMITED

Dates

Publication Date: 20260512
Application Date: 20220517

Claims (20)

1 . A method for adjusting an intensity of a power laser beam applied to a semiconductor device by a power laser, wherein an applied intensity of the power laser beam is indicative of a magnitude at which the power laser beam is emitted toward the semiconductor device and wherein a reflection intensity of a probing laser beam applied to the semiconductor device is indicative of an emissivity of the semiconductor device, comprising: measuring the reflection intensity of the probing laser beam applied by a probing laser to determine the emissivity of the semiconductor device, wherein the probing laser is different than the power laser; and adjusting the applied intensity of the power laser beam as a function of the emissivity.
2 . The method of claim 1 , the adjusting comprising: adjusting the applied intensity to achieve a desired reflection intensity.
3 . The method of claim 1 , the adjusting comprising: adjusting an amount of power supplied to the power laser emitting the power laser beam; and applying the power laser beam to the semiconductor device to perform an anneal operation.
4 . The method of claim 1 , comprising: applying the power laser beam to the semiconductor device with a power laser beam size; and applying the probing laser beam to the semiconductor device with a probing laser beam size less than the power laser beam size while applying the power laser beam to the semiconductor device.
5 . The method of claim 4 , wherein the semiconductor device has a semiconductor device size, comprising: adjusting the power laser beam size based on the semiconductor device size.
6 . The method of claim 1 , comprising: applying the power laser beam to the semiconductor device with a power laser beam width and a power laser beam length; and applying the probing laser beam to the semiconductor device with a probing laser beam width less than the power laser beam width and a probing laser beam length less than the power laser beam length while applying the power laser beam to the semiconductor device.
7 . The method of claim 1 , comprising: applying the probing laser beam to the semiconductor device as a polarized probing laser beam.
8 . The method of claim 1 , comprising: adjusting an angle of incidence of the probing laser beam to reduce absorption by the semiconductor device.
9 . The method of claim 1 , comprising: measuring thermal emission from the semiconductor device to obtain a measured intensity; calculating a read temperature of the semiconductor device based on the measured intensity and the emissivity; and comparing the read temperature to a set temperature of the semiconductor device for performing an anneal operation on the semiconductor device to determine a degree of deviation.
10 . The method of claim 9 , the adjusting comprising: adjusting the applied intensity when the degree of deviation exceeds a threshold; and not adjusting the applied intensity when the degree of deviation does not exceed the threshold.
11 . A method of annealing a semiconductor device, comprising: applying a power laser beam by a power laser to the semiconductor device to anneal a layer of the semiconductor device; measuring thermal emission from the layer of the semiconductor device to obtain a measured intensity; applying a probing laser beam by a probing laser to the layer of the semiconductor device, wherein the probing laser is different than the power laser; measuring a reflection intensity of the probing laser beam, the reflection intensity indicative of an emissivity of the layer of the semiconductor device; and adjusting an applied intensity of the power laser beam as a function of the measured intensity and the emissivity, the applied intensity of the power laser beam indicative of a magnitude at which the power laser beam is emitted toward the layer of the semiconductor device.
12 . The method of claim 11 , wherein adjusting the applied intensity of the power laser beam comprises: calculating a read temperature of the layer of the semiconductor device based on the measured intensity and the emissivity; and comparing the read temperature to a set temperature of the layer of the semiconductor device for annealing the layer of the semiconductor device to determine a degree of deviation.
13 . The method of claim 12 , wherein adjusting the applied intensity of the power laser beam comprises: adjusting the applied intensity when the degree of deviation exceeds a threshold by adjusting an amount of power supplied to the power laser emitting the power laser beam.
14 . The method of claim 11 , wherein: applying the power laser beam comprises modulating the power laser beam at a first frequency, and applying the probing laser beam comprises modulating the probing laser beam at a second frequency different than the first frequency.
15 . The method of claim 11 , wherein measuring the thermal emission from the layer of the semiconductor device comprises measuring the thermal emission from the layer of the semiconductor device by a first emission detector configured to detect the measured intensity of the thermal emission from the layer of the semiconductor device at a first wavelength.
16 . The method of claim 15 , wherein: measuring the thermal emission from the layer of the semiconductor device comprises measuring the thermal emission from the layer of the semiconductor device by a second emission detector configured to detect a second measured intensity of the thermal emission from the layer of the semiconductor device at a second wavelength different than the first wavelength, and adjusting the applied intensity of the power laser beam comprises adjusting the applied intensity of the power laser beam as a function of the measured intensity, the second measured intensity, and the emissivity.
17 . The method of claim 16 , wherein: measuring the thermal emission from the layer of the semiconductor device comprises measuring the thermal emission from the layer of the semiconductor device by a third emission detector configured to detect a third measured intensity of the thermal emission from the layer of the semiconductor device at a third wavelength different than the first wavelength and different than the second wavelength, and adjusting the applied intensity of the power laser beam comprises adjusting the applied intensity of the power laser beam as a function of the measured intensity, the second measured intensity, the third measured intensity, and the emissivity.
18 . The method of claim 11 , wherein: applying the power laser beam comprising emitting the power laser beam from a CO 2 laser configured to emit the power laser beam at greater than 2000 watts, and applying the probing laser beam comprises emitting the probing laser beam at less than 100 milli watts and at a wavelength of less than 1 micrometer.
19 . The method of claim 11 , wherein: measuring the thermal emission from the layer of the semiconductor device comprises detecting the thermal emission from the layer of the semiconductor device as a photo-multiplier tube (PMT) count of atomic units of charge, and adjusting the applied intensity of the power laser beam as a function of the measured intensity and the emissivity comprises: calculating a read temperature of the layer of the semiconductor device based on the PMT count and the emissivity; comparing the read temperature to a set temperature of the layer of the semiconductor device for annealing the layer of the semiconductor device; and adjusting the applied intensity of the power laser beam based on the comparison of the read temperature to the set temperature.
20 . A method for annealing a semiconductor device, comprising: applying a power laser beam by a power laser to the semiconductor device to anneal a layer of the semiconductor device; measuring thermal emission from the layer of the semiconductor device due to the annealing by detecting the thermal emission from the layer of the semiconductor device as a photo-multiplier tube (PMT) count of atomic units of charge; determining an emissivity of the layer of the semiconductor device using a probing laser beam emitted by a probing laser different than the power laser; calculating a read temperature of the layer of the semiconductor device based on the PMT count and the emissivity; comparing the read temperature to a set temperature of the layer of the semiconductor device for annealing the layer of the semiconductor device; and adjusting an applied intensity of the power laser beam based on the comparison of the read temperature to the set temperature.

Description

BACKGROUND Semiconductor devices are electronic components that are fabricated on a semiconductor wafer. Using a variety of fabrication techniques, semiconductor devices are made and connected together to form integrated circuits. A number of integrated circuits may be grouped on semiconductor chip, which is diced from a semiconductor wafer. Such components and/or integrated circuits are capable of performing a set of useful operations in an electronic appliance. Examples of such electronic appliances are mobile telephones, personal computers, personal gaming devices, etc. Accordingly, semiconductor manufacturers are pressed to create smaller and faster semiconductor circuits that also consume less power (e.g., to improve energy efficiency and/or reduce battery consumption). Integrated circuits including field-effect transistors (FETs), such as complementary-metal-oxide-semiconductors (CMOSs), have grown in popularity due to this demand for smaller, faster, and/or more energy efficient circuitry. BRIEF DESCRIPTION OF THE DRAWINGS Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. FIG. 1 illustrates a cross-sectional view of a semiconductor device, according to some embodiments. FIG. 2 illustrates an implementation of laser beam adjustment for semiconductor fabrication, according to some embodiments. FIG. 3 illustrates an implementation of laser beam adjustment for semiconductor fabrication, according to some embodiments. FIG. 4 illustrates example components of a device, according to some embodiments. FIG. 5 illustrates an example method, according to some embodiments. FIG. 6 illustrates an example method, according to some embodiments. DETAILED DESCRIPTION The following disclosure provides several different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments or configurations discussed. Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation illustrated in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly. Also, relationship terms such as “connected to,” “adjacent to,” “coupled to,” and the like, may be used herein to describe both direct and indirect relationships. “Directly” connected, adjacent, or coupled may refer to a relationship in which there are no intervening components, devices, or structures. “Indirectly” connected, adjacent, or coupled may refer to a relationship in which there are intervening components, devices, or structures. Semiconductors are formed using a variety of operations. Example operations include, among other things, physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), plating, epitaxially growing, etc. Another operation frequently utilized is an anneal operation, where the semiconductor device (e.g., or a portion thereof, such as a single layer of the semiconductor device) is heated to change a property or properties of the semiconductor device. In some embodiments, one or more of such processes include the use of a power laser to perform an anneal operation. The power laser may be configured to apply a power laser beam to a region of the semiconductor wafer, a semiconductor device of the semiconductor wafer, a component of the semiconductor wafer, or other portion of the semiconductor wafer. For example, in some embodiments, the anneal operation includes using a power laser beam to heat the semiconductor device (e