Systems and methods for characterizing semiconductor materials

Abstract

A system and method for non-contact characterization of semiconductor devices. The system may include: an infrared radiation source that directs radiation toward the semiconductor device; a radiation guide positioned proximate the infrared radiation source, the radiation guide configured to direct radiation toward an opposite side of the semiconductor device, the semiconductor device being receivable between the radiation guide and the infrared radiation source; and a radiation detector positioned proximate the infrared radiation source, the radiation detector configured to sense radiation from the semiconductor device associated with a plurality of infrared bands to determine a dopant distribution property of the semiconductor device. The sensed radiation may include radiation originating from the infrared radiation source that is reflected from the semiconductor device. The sensed radiation may include radiation originating from the radiation guide and emitted from the semiconductor device. The dopant distribution property may be based on infrared reflectivity or infrared transmittance associated with the plurality of corresponding infrared bands.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 944,350, filed on December 5, 2019, entitled “SYSTEMS AND METHODS OF CHARACTERIZING SEMICONDUCTOR MATERIALS,” which is hereby incorporated by reference in its entirety. Technical Field

[0003] Various embodiments of the present disclosure relate generally to the field of semiconductors, and particularly to systems and methods for characterizing semiconductor devices. Background Art

[0004] Electronic devices, such as solar panels, can be constructed to include semiconductor devices. Semiconductor production can include processes for intentionally introducing impurities into undoped or intrinsic semiconductor materials. The process of introducing impurities into undoped or intrinsic semiconductors is referred to as doping. During semiconductor manufacturing, process control operations can be performed to determine whether the semiconductor substrate has been doped according to desired specifications. Summary of the Invention

[0005] The present disclosure provides non-contact systems and methods for characterizing semiconductor devices. Embodiments of the systems and methods can be based on infrared reflectometers that can be based on infrared reflectivity or infrared transmittance intensity measurements for determining dopant profile properties.

[0006] In some embodiments, the system can be configured to detect infrared radiation from a semiconductor device under test based on multiple infrared radiation bands, so that the slope and maximum / minimum values ​​of a curve associated with the sensed infrared radiation data can be identified and correlated with dopant profile properties. The dopant profile properties can include sheet resistance, etc. The multiple bands can be within the infrared spectrum and can include wavelengths from 1.2 μM to 20 μM. By determining the dopant profile properties of the semiconductor device under test, the system disclosed herein can identify perturbations from manufacturing process variations.

[0007] In some embodiments, the system can be configured to detect reflected radiation from the semiconductor device based on incident infrared radiation to determine infrared reflectivity properties associated with the semiconductor device. The incident infrared radiation directed toward the semiconductor device can originate from an infrared radiation source. The system disclosed herein can also be configured to detect radiation originating from the opposite side of the semiconductor device and emitted from the first side of the semiconductor device for determining infrared transmittance properties associated with the semiconductor device. The radiation directed from the opposite side of the semiconductor device can originate from a supplemental radiation source on the opposite side of the semiconductor device. In some other embodiments, the radiation directed from the opposite side of the semiconductor device can be reflected radiation originating from an infrared radiation source and penetrating the semiconductor device. Various embodiments of the system disclosed herein can determine dopant distribution properties associated with the semiconductor device based on one or a combination of the determined infrared reflectivity and infrared transmittance properties of the semiconductor device under test.

[0008] In one aspect, the present disclosure provides a system for non-contact characterization of a semiconductor device under test. The system may include: an infrared radiation source that directs radiation toward the semiconductor device; a radiation guide positioned proximate the infrared radiation source and configured to direct radiation toward an opposite side of the semiconductor device, the semiconductor device being receivable between the radiation guide and the infrared radiation source; and a radiation detector positioned proximate the infrared radiation source and configured to sense radiation associated with a plurality of infrared bands from the semiconductor device to determine a dopant distribution property of the semiconductor device, the sensed radiation including radiation originating from the infrared radiation source that is reflected from the semiconductor device, and the sensed radiation including radiation originating from the radiation guide and emitted from the semiconductor device. The dopant distribution property may be based on at least one of infrared reflectivity or infrared transmittance associated with the plurality of corresponding infrared bands.

[0009] In some embodiments, the radiation directing device may be a supplemental radiation source that emits radiation toward the semiconductor device that penetrates the semiconductor device, and a portion of the radiation that penetrates the semiconductor device may be detected by the radiation detector to determine infrared transmittance associated with the semiconductor device.

[0010] In some embodiments, the supplemental radiation source and the infrared radiation source may direct radiation from opposite sides toward the semiconductor device at different modulation frequencies. The radiation detector may demodulate the sensed radiation from the semiconductor device to determine infrared reflectivity or infrared transmittance.

[0011] In some embodiments, the radiation-directing device may include a paddle configured to convey the semiconductor device proximal to the infrared radiation source and the radiation-directing device. The paddle may include a high-reflectivity background that reflects radiation toward the semiconductor device, the reflected radiation being based on radiation emitted from the infrared radiation source.

[0012] In some embodiments, the high reflectivity background may comprise at least one of aluminum or gold.

[0013] In some embodiments, the paddle may include a low reflectivity background positioned adjacent to the high reflectivity background.The low reflectivity background may include at least one of an optically opaque material or an aperture through which incident radiation passes.

[0014] In some embodiments, the low reflectivity background may be associated with a first sensing location and the high reflectivity background may be associated with a second sensing location, the radiation from the infrared radiation source being emitted towards the first and second sensing locations.

[0015] In some embodiments, the separation distance between the first sensing location and the second sensing location may be based on an expected spatial uniformity of the semiconductor device under test.

[0016] In some embodiments, in response to radiation emitted from the infrared radiation source toward the first sensing location, the radiation detector may be configured to sense reflected radiation from the semiconductor device to determine infrared reflectivity.

[0017] In some embodiments, in response to radiation emitted from the infrared radiation source toward the second sensing location, the radiation detector may be configured to sense radiation reflected from the radiation guiding device and transmitted through the semiconductor device to determine infrared transmittance.

[0018] In some embodiments, the paddle may be configured to transfer the semiconductor device from the first sensing location to the second sensing location or from the second sensing location to the first sensing location.

[0019] In some embodiments, the plurality of wavelength bands may be along a wavelength spectrum ranging from 1.2 μM to 20 μM.

[0020] In some embodiments, at least one of the plurality of wavelength bands may overlap with an adjacent wavelength band in the wavelength band spectrum from 1.2 μM to 20 μM.

[0021] In some embodiments, the dopant profile property of the semiconductor device may include sheet resistance or dopant surface concentration.

[0022] In another aspect, the present disclosure provides a method for non-contact characterization of a semiconductor device. The method may include: detecting a first radiation sample associated with a plurality of infrared bands from a first location, the first radiation sample comprising radiation originating from an infrared radiation source and reflected from a first side of the semiconductor device; detecting a second radiation sample associated with the plurality of infrared bands, the second radiation sample comprising radiation originating from a radiation-guiding device located on an opposite side of the semiconductor device, the second radiation sample being based on radiation emitted from the first side of the semiconductor device; and determining a dopant distribution property associated with the semiconductor device based on at least one of infrared reflectivity or infrared transmittance, the infrared reflectivity being determined based on the detected first radiation sample and the infrared transmittance being determined based on the detected second radiation sample.

[0023] In some embodiments, the radiation-directing device may include a reflective paddle having a low-reflectivity portion and a high-reflectivity portion. The first radiation sample may be detected when the infrared radiation is directed toward a first location of the semiconductor device adjacent to the low-reflectivity background. The second radiation sample may be detected when the infrared radiation is directed toward a second location of the semiconductor device adjacent to the high-reflectivity background.

[0024] In some embodiments, the method may include positioning the reflective paddle to direct infrared radiation from the infrared radiation source toward the first position of the semiconductor device adjacent to the low reflectivity background; and positioning the reflective paddle to direct infrared radiation from the infrared radiation source toward the second position of the semiconductor device adjacent to the high reflectivity background in response to detecting the first radiation sample.

[0025] In some embodiments, the separation distance between the first sensing location and the second sensing location may be based on an expected spatial uniformity of the semiconductor device under test.

[0026] In some embodiments, the radiation-directing device may include a supplemental radiation source that emits radiation that penetrates the semiconductor device toward the semiconductor device. The second radiation sample may be based on radiation originating from the supplemental radiation source and exiting the first side of the semiconductor device for determining infrared transmittance associated with the semiconductor device.

[0027] In some embodiments, the infrared radiation source and the supplemental radiation source may emit infrared light at different modulation frequencies, respectively.The method may include demodulating the first radiation sample and the second radiation sample.

[0028] In some embodiments, the plurality of infrared bands includes bands along the spectrum from 1.2 μM to 20 μM.

[0029] In another aspect, the present disclosure provides a radiation detector for contactless characterization of a semiconductor device that can be housed between a radiation-guiding device and an infrared radiation source. The radiation guide may include one or more radiation sensors, a processor coupled to the one or more radiation sensors, and a memory storing processor-executable instructions that, when executed, configure the processor to perform one or more operations for characterizing the semiconductor device. The radiation detector may be located proximate to the infrared radiation source, which may emit radiation toward the semiconductor device. The processor may execute operations to configure the radiation detector to sense radiation associated with a plurality of infrared bands from the semiconductor device to determine a dopant profile property of the semiconductor device. The sensed radiation may include radiation originating from the infrared radiation source and reflected from the semiconductor device. The sensed radiation may also include radiation originating from the radiation-guiding device that penetrates the semiconductor device and exits the semiconductor device. The radiation-guiding device may be located proximate to the infrared radiation source and configured to direct radiation toward a side opposite the semiconductor device. The processor may be configured to determine the dopant profile property based on at least one of infrared reflectivity or infrared transmittance associated with the plurality of corresponding infrared bands.

[0030] In another aspect, a non-transitory computer-readable medium or medium having machine-interpretable instructions stored thereon, which, when executed by a processor, may cause the processor to perform one or more methods described herein.

[0031] In various further aspects, the present disclosure provides corresponding systems and apparatus, as well as logical structures, such as machine-executable sets of coded instructions, for implementing such systems, apparatus, and methods.

[0032] In this regard, before explaining at least one embodiment in detail, it should be understood that the embodiments are not limited in application to the details of construction or arrangement of components set forth in the following description or illustrated in the accompanying drawings. Furthermore, it should be understood that the phraseology and terminology employed herein are for illustrative purposes and should not be considered limiting.

[0033] After reading this disclosure, those skilled in the art will appreciate many additional features and combinations thereof regarding the embodiments described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In the accompanying drawings, various embodiments are shown by way of example. It should be expressly understood that the description and drawings are for illustrative purposes only and serve as an aid to understanding.

[0035] Various embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0036] Figure 1 A graph showing the infrared reflectance and infrared transmittance of a set of double-sided diffused textured wafers detected by Fourier-transform infrared spectroscopy (FTIR) is presented;

[0037] Figure 2 presents graphs showing FTIR-detected reflectance and transmittance on sample wafers having similar dopant layer sheet resistance but different dopant distributions;

[0038] Figure 3 Figures showing FTIR scans of two sets of wafers with similar doped layer sheet resistance and dopant distribution but with different texture pyramid sizes are presented;

[0039] Figure 4A and 4B shows a partial cross-sectional elevation view of a system for determining dopant profile properties of a semiconductor device under test according to various embodiments of the present disclosure;

[0040] Figure 5 A top view of an apparatus for transporting a semiconductor device located near an infrared radiation source and an infrared detection device according to various embodiments of the present disclosure is shown;

[0041] Figure 6 presents a graph showing reflectivity measurement accuracy data for a series of displacement measurement positions on a wafer under test according to various embodiments of the present disclosure;

[0042] Figure 7 shows a partial cross-sectional elevation view of a system for determining dopant profile properties of a semiconductor device according to various embodiments of the present disclosure;

[0043] Figure 8 A perspective view of a system for characterizing a semiconductor device according to an embodiment of the present disclosure is shown;

[0044] Figure 9 Shown Figure 8 A side elevation view of the system;

[0045] Figure 10 A flow chart of a method for non-contact characterization of a semiconductor device according to an embodiment of the present disclosure is shown;

[0046] Figure 11 A flowchart of a method for non-contact characterization of a semiconductor device according to an embodiment of the present disclosure is shown; and

[0047] Figure 12 A block diagram of a computing device according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0048] Semiconductor device manufacturing can include processes for intentionally introducing impurities into undoped or intrinsic semiconductor materials. In some instances, semiconductor wafers can be doped with one or more materials to modify the physical properties of the intrinsic semiconductor. For example, a semiconductor wafer can be placed in a phosphorus diffusion furnace, and a high-concentration phosphorus-doped layer can be formed on the surface of the wafer, thereby forming a PN junction. During semiconductor wafer manufacturing, it may be desirable to perform process control checks to determine whether the doped layer has properties that meet desired specifications.

[0049] Semiconductor manufacturing processes (e.g., solar cell manufacturing processes, integrated circuit device manufacturing processes, etc.) can be based on tightly controlled processes using, for example, diffusion and annealing furnaces and textured wet benches. With the increasing demand for cost reduction and efficiency improvement, evolving semiconductor manufacturing processes can be based on less tightly controlled processes, thereby increasing variations in dopant distribution, texture, substrate bulk resistance, etc. Unexpected variations in dopant distribution can result in the manufacture of semiconductor devices that may not conform to desired device specifications.

[0050] Process control operations can be performed to monitor the dopant profile to determine properties of the dopant profile, such as the sheet resistance of the semiconductor wafer. In some embodiments, a four-point probe can be used to measure electrical impedance and to determine the sheet resistance at one or more locations on the semiconductor wafer under test. Measuring sheet resistance based on a process utilizing a four-point probe may require that one or more probe tips be in physical contact with the semiconductor device under test.

[0051] It would be beneficial to provide systems and methods for determining semiconductor dopant profile properties based on non-contact operations and based on operations that are integrated or in-line with a semiconductor manufacturing process.

[0052] Infrared (IR) reflectometers may include operations for determining dopant profile properties of semiconductor doped layers based on reflection intensity measurements. As a non-limiting example, IR reflectometer operations may be used to characterize phosphorus-diffused silicon wafers during photovoltaic cell fabrication.

[0053] In some scenarios, the refractive index and extinction coefficient of a semiconductor material can vary depending on the free carrier concentration in the infrared spectrum (e.g., 1.2 μM to 20 μM wavelength). Due to free carrier absorption, the IR reflectivity at different wavelengths can be a function of the dopant profile of a doped semiconductor material (e.g., silicon). Such relationships can be identified to correlate the reflectivity intensity at different wavelengths with dopant profile properties such as sheet resistance. In some examples, correlating the reflectivity intensity with the dopant profile properties can be based on a reference expression or relationship.

[0054] As an illustrative example, a dopant profile property, such as sheet resistance, can be determined based on one or more expressions for combining or correlating the detected infrared signals. Embodiments of the expressions for determining the dopant profile property can be based on calibration data associated with a reference semiconductor device determined based on data detected by a reference measurement device, such as a 4-point probe device.

[0055] In scenarios where infrared radiation wavelengths may be greater than 1.2 μM, infrared light may penetrate semiconductor materials (eg, silicon wafers).In some embodiments, systems and methods may be configured to determine semiconductor properties based on IR reflectivity or IR transmittance measurements.

[0056] Fourier transform infrared spectroscopy (FTIR) or other forms of infrared reflectivity / transmittance measurements can be used to measure the dopant profile of a semiconductor device. In some scenarios, the dopant profile can be correlated with the detected infrared reflectivity or infrared transmittance across a range of infrared wavelengths or bands. Figures 1 to 3 Example data showing the correlation between dopant profile properties (eg, sheet resistance, pyramid size, etc.) and detected infrared transmittance / reflectance properties across multiple infrared bands are presented.

[0057] refer to Figure 1 , which shows a graph 100 showing FTIR-detected infrared reflectivity and infrared transmittance for a set of double-sided diffused textured wafers having different sheet resistances. FIG. 100 shows data for wafers having sheet resistances of 165 Ω / square, 136 Ω / square, 117 Ω / square, 96 Ω / square, 88 Ω / square, and 70 Ω / square. For ease of illustration, the data graphs of detected IR reflectivity and IR transmittance are labeled with reference numerals 165, 136, 117, 96, 88, and 70 to correspond to the corresponding sheet resistance values.

[0058] Figure 1 It is demonstrated that if measurements are taken across a range of infrared wavelengths or bands, the slope and minimum / maximum data of a curve (eg, a transmittance curve) can be measured and determined.

[0059] Figure 2 A graph 200 showing FTIR detected reflectance and transmittance on sample wafers having similar sheet resistance properties but different dopant profiles is presented. Figure 2 Graph 200 shows that high surface dopant concentrations can shift the reflectivity minimum to shorter infrared wavelengths.

[0060] Figure 3 Graph 300 is shown showing FTIR scans of two sets of wafers having similar doped layer sheet resistance and dopant distribution but different texture pyramid sizes. The doped layer sheet resistance and dopant distribution can be determined by operating an electrochemical capacitance-voltage technique. Figure 3 In the example data associated with graph 300 of FIG. 1 , the transmittance of “Group 1” wafers having larger pyramid sizes may be lower at mid-range infrared wavelengths.

[0061] Figure 2 and Figure 3 How different semiconductor device emitter distributions and textures (eg, as perturbations to the sheet resistance measurement device operation) may affect the infrared signal are shown, respectively.

[0062] It may be beneficial to provide systems and methods for determining dopant profile properties of semiconductor devices in order to filter out process disturbances during the manufacturing process. In various embodiments disclosed herein, the systems and methods may be configured to determine infrared reflectivity at a range of wavelengths / wavelength bands and to determine infrared transmittance at a similar range of wavelengths / wavelength bands to determine dopant profile properties of the semiconductor device under test.

[0063] It would be advantageous to provide systems and methods for integrating in-line dopant profile characterization operations with semiconductor device manufacturing operations to identify process defects or device yields based on contactless profiles of semiconductor devices in substantially real time. For example, the systems and methods disclosed herein can be integrated with semiconductor device manufacturing operations so that dopant profile variations indicative of process defects or yields exceeding desired semiconductor device specifications can be identified during the manufacturing process.

[0064] Various embodiments of the present disclosure provide a system for non-contact characterization of a semiconductor device under test. The system may include an infrared radiation source that directs radiation toward the semiconductor device; and a radiation guide positioned proximal to the infrared radiation source. The radiation guide may be configured to direct radiation toward opposite sides of the semiconductor device, and the semiconductor device may be received between the radiation guide and the infrared radiation source.

[0065] The system may include a radiation detector positioned proximate to the infrared radiation source and configured to sense radiation associated with a plurality of infrared bands from the semiconductor device to determine a dopant profile property of the semiconductor device. The sensed radiation may include radiation originating from the infrared radiation source and reflected from the semiconductor device. The sensed radiation may also include radiation originating from the radiation-guiding device and emitted from the semiconductor device.

[0066] In some embodiments, the radiation detector may include an infrared detector configured to sense infrared radiation or light across multiple wavelength bands. In some embodiments, the radiation detector may include signal processing circuitry for signal noise reduction or removal. In some embodiments, the radiation detector may include signal circuitry configured to separate a detected reflection signal from a detected transmission signal, for example, to determine infrared reflectivity or infrared transmittance properties associated with the semiconductor device under test.

[0067] In some embodiments, the radiation guiding device may be a reflecting device comprising a low reflectivity portion and a high reflectivity portion. For illustration, reference is made to Figure 4A and 4B , which illustrates a cross-sectional elevation view of a system 400 for determining dopant profile properties of a semiconductor device under test, according to various embodiments of the present disclosure.

[0068] exist Figure 4A and 4B In the embodiment of the present invention, the semiconductor device under test 480 can be a double-sided diffused textured wafer. As a non-limiting example, the semiconductor device under test 480 can be a phosphorus diffused silicon wafer used in photovoltaic cell manufacturing. Other types of silicon devices are contemplated.

[0069] Figure 4A Reflected light radiation is shown when a portion of the semiconductor device under test 480 is adjacent to the low reflectivity feature 422 . Figure 4B Reflected light radiation is shown when a portion of the semiconductor device under test 480 is adjacent to the high reflectivity feature 424 .

[0070] System 400 may include an infrared radiation source 410 and an infrared detection device 412. In some embodiments, infrared radiation source 410 may be configured to emit optical radiation in the infrared wavelength spectrum.

[0071] The infrared detection device 412 may include one or more sensors positioned to receive radiation reflected from the semiconductor device under test 480. In some embodiments, the infrared detection device 412 may include an integrating sphere configured to collect reflected radiation or light from the semiconductor device 480. The integrating sphere in combination with the one or more sensors may be configured to detect infrared reflectivity and infrared transmittance to determine a dopant profile property of the semiconductor device 480. Although examples of dopant profile properties may be described as including sheet resistance, other dopant profile properties of semiconductor devices are contemplated.

[0072] It may be beneficial to provide a system for determining properties of a dopant profile based on a combination of detected infrared reflectivity and infrared transmittance across a range of infrared radiation wavelengths or bands.

[0073] During system operation, infrared radiation source 410 can be configured to emit infrared light toward semiconductor device 480. For ease of illustration, the emitted infrared light is shown as light interacting with semiconductor device 480, and incident infrared light can interact with semiconductor device 480. At least a portion of the incident infrared light can be reflected from at least one of first device surface 482 or second device surface 484 (e.g., opposite sides of semiconductor device 480). Other portions of the incident infrared light can penetrate semiconductor device 480 toward second device surface 484 and toward an opposing radiation directing device. Figure 4A In , the radiation guiding means may comprise a non-reflective surface 422, such as a low reflectivity material. Figure 4B In the embodiment, the radiation guiding device may comprise a reflective surface 424, such as a highly reflective material.

[0074] exist Figure 4A , a portion of semiconductor device 480 is substantially positioned between: (i) infrared radiation source 410 and infrared detection device 412; and (ii) non-reflective surface 422. In some embodiments, non-reflective surface 422 may be a low-reflectivity material, such as an optical light-blocking material, and may be configured to suppress reflection of radiation or light incident on the low-reflectivity material.

[0075] For portions of semiconductor device 480 positioned adjacent to non-reflective surface 422 , infrared detection device 412 may substantially detect reflected infrared light associated with those portions of semiconductor device 480 to determine infrared reflectivity data.

[0076] exist Figure 4B, another portion of semiconductor device 480 can be positioned substantially between: (i) infrared radiation source 410 and infrared detection device 412; and (ii) reflective surface 424. In some embodiments, reflective surface 424 can comprise a highly reflective background material, such as gold or aluminum, and can be configured to reflect radiation or light incident on the highly reflective material back toward semiconductor device 480. Other types of highly reflective materials are contemplated.

[0077] During system operation, when infrared radiation source 410 emits infrared light toward semiconductor device 480, infrared detection device 412 can detect at least a portion of the infrared light incident on semiconductor device 480 that is reflected from at least one of first device surface 482 or second device surface 484. System 400 can be configured to determine infrared reflectivity data based on reflected light 450 from semiconductor device 480.

[0078] In addition, infrared detection device 412 can detect other portions of the incident infrared light that pass through semiconductor device 480 toward second device surface 484 and are reflected back from reflective surface 424 toward semiconductor device 480. In this example, the infrared light that is reflected from reflective surface 424 and returns through semiconductor device 480 toward infrared detection device 412 can be detected as dual transmitted light 460, and system 400 can be configured to determine infrared transmittance data based on dual transmitted light 460.

[0079] In some embodiments, infrared radiation source 410 can be configured to emit infrared light having a range of wavelengths for characterizing semiconductor device 480. As described in this disclosure, to identify process perturbations and more accurately measure dopant profile properties, it can be beneficial to determine infrared reflectivity and infrared transmittance based on detected infrared light across a range of infrared wavelengths.

[0080] As a non-limiting example, infrared radiation source 410 may be configured to emit eight or more wavelengths of infrared light toward semiconductor device 480 , and infrared detection device 412 may be configured to detect infrared light from semiconductor device 480 corresponding to respective wavelengths of the emitted infrared light.

[0081] By combining the determined infrared reflectivity data and infrared transmittance data based on: (a) a portion of the semiconductor device positioned adjacent to a low reflectivity material; and (b) a portion of the semiconductor device positioned adjacent to a high reflectivity material, system 400 can be configured to determine dopant profile properties, such as sheet resistance, thereby identifying process perturbations that may exceed desired specification values ​​during semiconductor device fabrication.

[0082] In some embodiments, an estimate of sheet resistance may be determined based on one or a combination of detected infrared reflectivity signals or infrared transmittance signals.System 400 may operate using a reference relationship providing dopant profile properties based on detected infrared signal inputs.

[0083] In some embodiments, the reference relationship for determining the dopant profile property can be based on multiple calibration measurements of a reference semiconductor device having known sheet resistance properties. In some embodiments, the calibration measurements can be based on four-point probe device measurements for determining the sheet resistance properties of the reference semiconductor device.

[0084] based on Figure 4A and 4B In the configuration disclosed in , the infrared detection device 412 can determine infrared reflectivity data based on a combination of reflected light 450 from the semiconductor device 480 , and can determine infrared transmittance data based on a combination of detected dual transmitted light 460 from the semiconductor device 480 .

[0085] In some embodiments, infrared detection device 412 may include a memory storing processor-executable instructions that, when executed, configure the processor to perform non-contact characterization operations for a semiconductor device. Infrared detector device 412 may include a processor coupled to the memory. Infrared detector device 412 may include one or more radiation sensors coupled to the processor, and the one or more radiation sensors may be positioned to receive radiation signals reflected from or transmitted through semiconductor device under test 480.

[0086] For example, the one or more radiation sensors may be positioned to receive the reflected light 450 or the dual transmitted light 460 illustrated in Figure 4. The one or more radiation sensors may be configured to determine energy levels associated with the reflected light 450 or the dual transmitted light 460 for estimating or inferring dopant profile properties of the semiconductor device 480.

[0087] In some embodiments, the processor of infrared detection device 412 can be coupled to infrared radiation source 410 and can be operated to control the emission properties of infrared light from infrared radiation source 410. For example, the memory can contain processor-executable instructions that configure the processor to modulate the emitted infrared radiation at a particular modulation frequency. Other operations for controlling infrared radiation source 410 are contemplated.

[0088] Therefore, in some embodiments, the infrared detection device 412 (eg, a radiation device) can be used for non-contact characterization of a semiconductor device, which can be housed between the radiation guide device and the infrared radiation source 410. Figure 4A and 4BIn the example of , the radiation guiding device can be a high reflectivity background or a low reflectivity background. Figure 4B In one embodiment, the radiation guiding device may be positioned proximate to the infrared radiation source and positioned to reflect radiation towards an opposite side of the semiconductor device.

[0089] Infrared detection device 412 can be positioned proximate to infrared radiation source 410, and infrared radiation source 410 can emit radiation toward the semiconductor device. Infrared detection device 412 can sense radiation associated with multiple infrared bands from the semiconductor device, and the processor can perform operations for determining dopant profile properties of the semiconductor device. The sensed radiation can include radiation originating from the infrared radiation source and reflected from the semiconductor device. The sensed radiation can also include radiation originating from a radiation-guiding device that penetrates the semiconductor device and exits for detection by infrared detection device 412.

[0090] In some embodiments disclosed herein, a processor may be coupled to or integrated with infrared detection device 412 and may execute processor-executable instructions for determining dopant profile properties based on infrared reflectivity or transmittance associated with the semiconductor device under test.

[0091] continue Figure 4A and 4B In order to detect the combination of reflected light 450 and dual transmitted light 460 from semiconductor device 480, in some embodiments, system 400 may include features for transporting semiconductor device 480 relative to infrared radiation source 410 and infrared detection device 412.

[0092] refer to Figure 5 , which shows a top view of an apparatus for conveying a semiconductor device 480 located proximate to an infrared radiation source 410 and an infrared detection device 412 ( FIG. 4 ) according to various embodiments of the present disclosure. The semiconductor device 480 under test may be a wafer, and the semiconductor device 480 may be supported by a reflective device 570. In some examples, the reflective device 570 may be a reference Figure 4A and 4B Examples of radiation guiding devices are described.

[0093] The semiconductor device 480 (eg, a wafer under test) is shown as having a substantially rectilinear shape with rounded corners. Other physical shapes or configurations of the semiconductor device 480 are contemplated, such as a circular wafer, etc.

[0094] Reflection device 570 may be a paddle configured to support or transport semiconductor device 480 from a diffusion boat toward system 400 to characterize semiconductor device 480 during a semiconductor manufacturing process.

[0095] For ease of explanation, Figure 5A semi-transparent top view of a semiconductor device 480 supported by a reflective device 570 is shown. Figure 5 The semi-transparent top view allows for display of alternating high and low reflectivity materials adjacent to the semiconductor device 480. Figure 5 , reflective device 570 can be located below semiconductor device 480. In some embodiments, reflective device 570 can include a plurality of alternating reflectivity portions, such as one or more low infrared reflectivity portions 572a and one or more high infrared reflectivity portions 572b. Other configurations or arrangements of reflectivity portions are contemplated.

[0096] Infrared radiation source 410 ( FIG. 4 , Figure 5 ) can be configured to emit infrared light toward the semiconductor device 480 under test, and the infrared detection device 412 ( FIG. 4 , Figure 5 590) can be configured to detect reflected light 450 from semiconductor devices 480 associated with a series of example positions around the wafer under test and detect dual transmitted light 460. For ease of illustration, the series of example positions can be highlighted by circular markers along the movement pattern 590.

[0097] In some embodiments, the infrared radiation source 410 and the infrared detection device 412 (located at Figure 5 The reflective device 570 can be configured to continuously position the semiconductor device 480 relative to the infrared radiation source 410 and the infrared detection device 412 so that the infrared radiation source 410 can emit infrared light (incident on the surface of the semiconductor device 480) and the infrared detection device 412 can detect at least one of the reflected light 450 or the dual transmitted light 460 at corresponding positions along the movement pattern 590.

[0098] For example, when the infrared radiation source 410 emits infrared light at the first position 592 adjacent to the low reflectivity portion 572a, the infrared detection source 412 may detect the reflected light 450 ( Figure 4A When the infrared radiation source 410 emits infrared light at the second position 594 adjacent to the high reflectivity portion 572b, the infrared detection source 412 can detect the combination of the reflected light 450 and the dual transmitted light 460 ( Figure 4B ).

[0099] Infrared detection device 412 may be configured to determine a dopant profile property, such as sheet resistance, based on a combination of reflectivity data associated with first location 592 and reflectivity / transmittance data associated with second location 594 .

[0100] continue Figure 5In the example shown in , the system can be configured to transmit the reflection device 570 so that reflected light or dual transmitted light from the semiconductor device 480 (e.g., a wafer under test) can be detected at area groups with low reflectivity background and high reflectivity background.

[0101] In some embodiments, at corresponding locations along the movement path 590, the infrared detection device 412 can be configured to determine reflectance data or transmittance data based on a number of wavelengths along the infrared spectrum, thereby identifying disturbances based on manufacturing process variations such as surface texture, emitter diffusion distribution, or bulk sheet resistance. In some embodiments, the number of wavelengths can include eight wavelengths along the spectrum from 1.2 μM to 20 μM. Detecting reflected light 450 or dual transmitted light 460 based on eight wavelengths of infrared light is an example, and any number of infrared light wavelengths are contemplated.

[0102] The semiconductor device under test 480 may not be substantially uniform and, thus, may have significant dopant profile variations across the semiconductor device 480. In the present example where the semiconductor device 480 may not be substantially uniformly doped, determining dopant profile properties may be challenging at least because detecting reflected light 450 (associated with a low reflectivity background) and detecting reflected light 450 / dual transmitted light 460 (associated with a high reflectivity background) may not provide representative data for determining reflectivity or transmittance properties of the semiconductor device. In the scenario where the semiconductor device 480 may not be substantially uniformly doped, the dopant profile properties may differ significantly at the first location 592 relative to the second location 594.

[0103] Thus, in some embodiments, system 400 can be configured to arrange first location 592 and second location 594 within a threshold distance of each other based on an expected degree of spatial uniformity of semiconductor device under test 480. In some examples, spatial uniformity of a dopant can be associated with a concentration of the dopant per unit area or volume of the semiconductor device.

[0104] For example, the system 400 can be configured such that the first position 592 and the second position 594 along the movement path 590 can be located within an area of ​​approximately 20 mm by 20 mm. Figure 6 As will be shown in the example, system 400 may determine that for semiconductor devices 480 having a specified degree of spatial uniformity, there may be no appreciable degradation in characterization accuracy when a first measurement location 592 of a pair is within 20 mm of another measurement location 594 .

[0105] refer to Figure 6, which shows a graph 600 of reflection measurement accuracy for a series of displacement measurement locations on a wafer under test for two example wafer sets according to various embodiments of the present disclosure.

[0106] Graph 600 illustrates a series of measurement accuracy data points associated with relative distances between pairs of measurement locations from which infrared detection device 412 can detect light. For example, a corresponding measurement location pair may include reflective device 570 ( Figure 5 )'s first positioning on a low-reflectivity background and a second positioning on a high-reflectivity background.

[0107] In this example, Figure 6 Graph 600 shows that when a pair of adjacent measurement locations (associated with a low reflectivity / high reflectivity background) are within 20 mm of each other, there may be minimal deviation in reflectivity data accuracy. The 20 mm threshold is only an example, and the threshold governing the spacing of adjacent measurement point pairs may depend on the degree of expected spatial uniformity of the semiconductor device 480 under test. For example, when the expected degree of spatial uniformity of the semiconductor device 480 is high, the threshold may be higher than when the expected degree of spatial uniformity of the semiconductor device 480 is low.

[0108] Reference is made to Table 1 (below), which summarizes a set of regression data associated with two groups of phosphorus-diffused silicon wafers according to an embodiment of the present disclosure. The regression data may be based on operations performed by various embodiments of the system disclosed herein.

[0109]

[0110]

[0111]

[0112] Table 1 contains regression data associated with scenarios when measurements (e.g., light detected from a wafer under test by infrared detection) are associated with a portion of the wafer adjacent to: (a) only a low reflectivity background (e.g., a black background material); (b) only a high reflectivity background (e.g., a gold background material); and (c) a combination of low and high reflectivity backgrounds (similar to reference 1). Figure 5 The regression data associated with light detected from a wafer adjacent to a combined low reflectivity / high reflectivity background is based on 16 data points (e.g., 8 data points associated with the low reflectivity background only and 8 data points associated with the high reflectivity background only).

[0113] In the experiments summarized by the regression data in Table 1, the reference measurements were performed based on operation using a four-point probe. When comparing the determined / measured dopant profile properties based on (a) the systems and methods disclosed herein; and (b) the operation of a reference measurement tool, such as that associated with a four-point probe, Table 1 shows improvements associated with a coefficient of determination (R2), reduced accuracy (e.g., mean absolute error), and a frequency of change in sheet resistance greater than 10 (as an example of a dopant profile property), with two wafer groups (1 and 2) showing an improvement associated with 10Ω / square. In some examples described herein, the coefficient of determination can describe how closely the measured sheet resistance fits a determined relationship or expression. In some examples described herein, verification accuracy can also describe how closely the measured sheet resistance fits a determined relationship or expression.

[0114] Figure 5 A reflective device 570, such as a paddle, is included that has one or more alternating low-reflectivity / high-reflectivity background portions. The reflective device 570 can be configured to transport the wafer under test proximate to the infrared radiation source 410 ( FIG. 4 ) and the infrared detection device 412 ( FIG. 4 ). Over time, as the reflective device 570 picks up and supports the semiconductor wafer, the reflective background portion can become susceptible to wear and may erode. The worn or otherwise eroded high-reflectivity background portion can exhibit a reduced ability to reflect infrared light back toward the wafer under test, thereby reducing the accuracy of the system and method for determining dopant profile properties.

[0115] Provided is a system and method for detecting reflected and dual-transmitted light to detect reflectance data and transmittance data of a wafer under test, thereby determining dopant distribution properties of the wafer under test while reducing the need for Figure 5 The dependence of the reflectivity on the background fraction shown in may be helpful.

[0116] refer to Figure 7 , which illustrates a partial cross-sectional elevation view of a system 700 configured to determine dopant profile properties of a semiconductor device 780 according to various embodiments of the present disclosure. Figure 7 In the embodiment, the semiconductor device 780 can be a double-sided diffused textured wafer, similar to Figure 4A and 4B Other types of semiconductor devices under test 780 are contemplated.

[0117] System 700 includes a first infrared radiation source 710a and an infrared detection device 712. In some embodiments, first infrared radiation source 710a can emit optical radiation in the infrared wavelength spectrum.

[0118] The infrared detection device 712 may include one or more sensors positioned to receive infrared light from the semiconductor device under test 780. In some embodiments, the infrared light received from the semiconductor device 780 may be infrared light originating from the first infrared radiation source 710a and reflected from at least one of the first device surface 782 or the second device surface 784 (collectively referred to as reflected light 750, similar to the reference image). Figure 4A The infrared light reflected from the second device surface 784 can be based on a portion of the light that penetrates the first device surface 782 and transmits through the semiconductor device 784 to reach the second device surface 784.

[0119] In some embodiments, infrared detection device 712 may be configured to determine infrared reflectivity data based at least on reflected light 750 received from semiconductor device 780 .

[0120] Again briefly refer to Figure 4B , the infrared detection device 412 is configured to determine infrared transmittance data based on at least the dual transmitted light 460. Figure 4B In the example shown, dual transmitted light 460 partially includes infrared light that penetrates semiconductor device 480 and reflects from reflective surface 424 back through semiconductor device 480 for detection by infrared detection device 412. In some scenarios (as described above), reflective surface 424 may be worn or eroded, at least due to repeated contact with the transported semiconductor device under test 480. It may be beneficial to provide an alternative system that does not rely on reflective device 570, which may be worn or eroded over time.

[0121] Reference again Figure 7 In some embodiments, the infrared detection device 712 can be configured to determine dopant distribution properties (e.g., sheet resistance, etc.) based on infrared light emitted by a first infrared radiation source 710a positioned near the first device surface 782 and a second infrared radiation source 710b positioned near the second device surface 784 (e.g., the opposite surface of the first device surface 782).

[0122] In order to improve and maintain the reflective device 570 ( Figure 5 ), system 700 can include a second infrared radiation source 710b to emit infrared light toward second device surface 784, thereby allowing at least a portion of the emitted infrared light (e.g., having a wavelength suitable for penetrating semiconductor devices) to be transmitted toward first device surface 782 and through the first device surface toward infrared detection device 712. Second infrared radiation source 710b can be an example of a radiation directing device disclosed herein.

[0123] Infrared light originating from second infrared radiation source 710 b and transmitted through the semiconductor device toward infrared detector device 712 can be detected as transmitted light emitted from first device surface 782 as transmitted light 760. In some scenarios, transmitted light 760 can also be based in part on infrared light that may have penetrated semiconductor device 780 and reflected at least once from first device surface 782 and second device surface 784 before being emitted as transmitted light 760 toward infrared detection device 760.

[0124] can be based on penetrating the semiconductor and reflected by the reflective surface 424 ( Figure 4B ) reflected back through the semiconductor device under test and provided in other ways (e.g., double transmitted light 460) can alternatively be provided by Figure 7 Thus, configuring and positioning the second infrared radiation source 710b proximal to the second device side 784 can improve the performance of maintaining the paddle (e.g., Figure 5 Challenges associated with the reflective surface of the reflecting device 570).

[0125] In some embodiments, the semiconductor device 780 may be provided by a paddle device ( Figure 7 Not shown) is transmitted and supported between the infrared radiation source (710a, 710b) and the infrared detection device 712, and the paddle device has a hole that allows infrared light from the second infrared radiation source 710b to transmit through the semiconductor device 780 and be detected by the infrared detection device 712.

[0126] In some embodiments, the second infrared radiation source 710b can emit infrared light having a modulation frequency different from the modulation frequency of the infrared light emitted from the first infrared radiation source 710a. The infrared detection device 712 can be configured to demodulate the detected infrared light, thereby separating the infrared light originating at least in part from the respective infrared radiation sources (710a, 710b).

[0127] To illustrate, in some embodiments, the first infrared radiation source 710a may emit an infrared source signal modulated at 1 KHz, and the second infrared radiation source 710b may emit an infrared source signal modulated at a frequency that may be 30% or 40% greater or less than the modulation frequency of the first infrared radiation source 710a.

[0128] In some other embodiments, the first infrared radiation source 710a and the second infrared radiation source 710b may emit infrared source signals that are time-modulated (eg, time-modulated / demodulated).

[0129] In some scenarios, when characterizing semiconductor devices based on the operations disclosed herein, frequency modulation / demodulation of an emitted infrared source signal may be more advantageous or relatively faster than time modulation / demodulation of an emitted infrared source signal. For example, if the operations for characterizing semiconductor devices are configured to characterize a wafer in less than 0.6 seconds per semiconductor device, a method based on frequency modulation / demodulation of an infrared source signal may be beneficial.

[0130] To identify semiconductor perturbations during manufacturing and to more accurately measure dopant profile properties, it may be beneficial to determine infrared reflectivity and infrared transmittance based on detected infrared light across a range of infrared wavelengths. Thus, in some embodiments, each of the infrared radiation sources (710a, 710b) may be configured to emit infrared light having a range of wavelengths for characterizing semiconductor device 780.

[0131] Figure 4 and Figure 7 The system (400, 700) can be configured to determine a dopant distribution property of a semiconductor device under test (e.g., a wafer) based on one or a combination of determined reflectivity data or transmittance data based on a plurality of infrared bands empirically measured at the semiconductor device under test. Determining one or more dopant distribution properties of the semiconductor device under test can be based on a set of one or more infrared radiation sources and infrared detection devices (412, 712), thereby reducing the amount of equipment used to screen semiconductor devices consistent with manufacturing operations.

[0132] In some embodiments, reference Figure 7 The disclosed infrared detection device 712 may include a memory storing processor-executable instructions that, when executed, configure the processor to perform operations for non-contact characterization of a semiconductor device. The infrared detector device 712 may include a processor coupled to the memory, and the infrared detector device 712 may include one or more radiation sensors coupled to the processor. The one or more radiation sensors may be positioned to receive radiation signals reflected from or transmitted through the semiconductor device under test 780.

[0133] For example, the one or more radiation sensors may be positioned to receive reflected light 750 or transmitted light 760 to estimate or infer dopant profile properties of semiconductor device 780 .

[0134] In some embodiments, the processor of the infrared detection device 712 can be coupled to the first infrared radiation source 710a or the second infrared radiation source 710b. In some embodiments, the memory can store processor-executable instructions that, when executed, configure the processor to operate to control the properties of the infrared light emitted from the infrared radiation source 410. For example, the processor can operate to control the modulation frequency of the infrared light emitted from the first infrared radiation source 710a or the second infrared radiation source 710b, respectively. In this example, the infrared detection device 712 can be based on Figure 7 The reflected light 750 or the transmitted light 760 shown in FIG. 7 determines the infrared reflectivity or infrared transmittance property. Other operations for controlling the infrared radiation sources 710a, 710b are contemplated.

[0135] refer to Figure 8 , which shows a perspective view of a system 800 for characterizing a semiconductor device (e.g., a wafer under test) according to an embodiment of the present disclosure. The system 800 can be configured to determine dopant distribution properties, such as sheet resistance, of a wafer being conveyed through the system 800. In some embodiments, the system 800 can be configured to determine other dopant distribution properties, such as surface concentration. The dopant surface concentration can be the concentration of dopant atoms near the surface of the semiconductor device (e.g., wafer) in atoms / cm 3 Other dopant profile properties can be envisioned.

[0136] System 800 may include an emitter / detection module 805 positioned proximate to a transmission module 825. A semiconductor wafer under test may be transported between emitter / detection module 805 and transmission module 825. Transmission module 825 may include a second infrared radiation source for emitting infrared light toward an opposite side of the wafer under test. In some scenarios, the infrared light from transmission module 825 may have a wavelength that penetrates the wafer under test, thereby exiting from an opposite side of the wafer under test.

[0137] Figure 9 Shown Figure 8 The wafer under test 880 can be transported between the emitter / detection module 805 and the transmission module 825 by a paddle (not shown) or other transport means. The emitter / detection module 805 can be configured to include a first infrared radiation source and an infrared detection device, similar to the reference Figure 4A 、 4B In addition, the transmission module 825 may include a similar Figure 7 The second radiation source 710b is a second radiation source.

[0138] Based on various embodiments having features disclosed herein, system 800 can detect and determine infrared reflectivity and transmittance at multiple bands (e.g., 8 wavelengths within the infrared spectrum) to determine dopant distribution properties associated with the wafer under test 880 (e.g., wafer sheet resistance).

[0139] Various embodiments of the present disclosure may include a system configured to perform a method for non-contact characterization of a semiconductor device. Figure 10 and Figure 11 A flow chart of a method for non-contact characterization of a semiconductor device according to various embodiments of the present disclosure is shown. In some embodiments, the operation can be performed by a system, such as reference Figure 4A and 4B The system 400 described or referenced Figure 7 The processor of the described system 700 may be coupled to or integrated with the radiation detector and may execute processor-executable instructions to determine a dopant profile property based on infrared reflectivity or transmittance associated with the semiconductor device under test.

[0140] As disclosed herein, in some embodiments, an infrared detection device or radiation detector may include one or more radiation sensors, a processor coupled to the one or more radiation sensors, and a memory storing processor-executable instructions that, when executed, configure the processor to perform Figure 10 Method 1000 or Figure 11 One or more operations in method 1100.

[0141] In some embodiments, the system can detect a first radiation sample associated with a plurality of infrared bands from a first location.The first radiation sample can include radiation originating from an infrared radiation source and reflected from a first side of the semiconductor device.

[0142] The system can detect a second radiation sample associated with a plurality of infrared radiation bands. The second radiation sample can include radiation originating from a radiation directing device positioned on an opposite side of the semiconductor device. The second radiation sample can be based on radiation emitted from the first side of the semiconductor device.

[0143] The system can determine a dopant profile property associated with a semiconductor device based on a first radiation sample and a second radiation sample based on the operations disclosed herein. For example, the dopant profile property can be based on at least one of (i) infrared reflectivity determined based on the detected first radiation sample and (ii) infrared transmittance determined based on the detected second radiation sample.

[0144] In some embodiments, the dopant profile property may be sheet resistance or dopant surface concentration, among others.

[0145] In some embodiments, the plurality of infrared bands may be wavelengths along a spectrum from 1.2 μM to 20 μM.

[0146] Figure 10 1 shows a flow chart of a method 1000 for non-contact characterization of a semiconductor device according to various embodiments of the present disclosure. Figure 4A and Figure 4B The depicted system 400 may be configured to perform the operations of method 1000 .

[0147] At operation 1002, the system detects a first radiation sample associated with a plurality of infrared bands from a first location. The first radiation sample includes radiation originating from an infrared radiation source and reflected from a first side of a semiconductor device.

[0148] In response to detecting the first radiation sample, the system may position a reflective paddle (e.g., transporting the semiconductor device under test) such that an infrared radiation source can direct infrared radiation toward a second location of the semiconductor device at operation 1004. The second location may be associated with incident infrared radiation adjacent to a highly reflective background at the second location such that infrared radiation that penetrates the semiconductor device can be reflected back toward the semiconductor device.

[0149] The radiation guiding means may comprise a reflective paddle having a low reflectivity portion and a high reflectivity portion as described herein with reference to Figure 4A 、 4B and 5. In this example, the first radiation sample can be detected when the infrared radiation is directed toward a first location of the semiconductor device adjacent to a low-reflectivity background. In some examples, the first radiation sample can be detected when the infrared radiation is directed toward the first location of the semiconductor device, where a radiation-guiding device adjacent to the first location of the semiconductor device may not be present. When the radiation-guiding device adjacent to the first location may not be present, incident infrared radiation that penetrates the opposite side of the semiconductor device may not be reflected back toward the opposite side of the semiconductor device.

[0150] At operation 1006, the system may detect a second radiation sample associated with the plurality of infrared bands. The second radiation sample may be based on radiation originating from a radiation-directing device positioned on an opposite side of the semiconductor device. The second radiation sample may be based on radiation emitted from the first side of the semiconductor device.

[0151] The second radiation sample may be detected while infrared radiation is directed toward a second location of the semiconductor device adjacent the high reflectivity background.

[0152] Thus, the method may include the operation of iteratively positioning the reflective paddle to direct infrared radiation from the infrared radiation source toward a first location adjacent to a low-reflectivity background of the semiconductor device. Additionally, in response to detecting the first radiation sample, the operation may include positioning the reflective paddle to direct infrared radiation from the infrared radiation source toward a second location adjacent to a high-reflectivity background of the semiconductor device.

[0153] In some embodiments, the spacing distance between the first location and the second location can be based on the expected spatial uniformity of the semiconductor device under test. For example, when the semiconductor device under test is expected to have a high degree of spatial uniformity, the distance between the first location and the second location can be approximately 20 mm. Other distances are contemplated.

[0154] At operation 1008, the system may determine a dopant profile property associated with the semiconductor device based on the first radiation sample and the second radiation sample. The dopant profile property may be based on at least one of (i) infrared reflectivity determined based on the detected first radiation sample and (ii) infrared transmittance determined based on the detected second radiation sample.

[0155] Although the system may position the reflective paddle at operation 1004 to adjust the position at which the infrared radiation source directs infrared radiation toward the semiconductor device, in some other embodiments, the reflective paddle may be substantially stationary and the infrared radiation source / infrared detector may be configured to advance along the semiconductor device to determine the infrared transmittance or infrared reflectance at multiple locations around the semiconductor device under test.

[0156] In some other embodiments, the radiation guiding device may include a supplementary radiation source for emitting radiation penetrating the semiconductor device from an opposite side of the semiconductor device toward the semiconductor device. For example, the supplementary radiation source may be Figure 7 In this example, the second radiation sample can be based on radiation from the supplemental radiation source that penetrates the semiconductor device and exits from the first side of the semiconductor device for determining infrared transmittance associated with the semiconductor device.

[0157] To illustrate, Figure 11 A flow chart of a method 1100 for non-contact characterization of a semiconductor device according to various embodiments of the present disclosure is shown. Figure 7 The described system 700 may be configured to perform the operations of method 1100 .

[0158] At operation 1102, the system detects a first radiation sample associated with a plurality of infrared bands. The detected first radiation sample may be based on infrared radiation reflected from the semiconductor device under test. The infrared radiation may originate from a first infrared radiation source 710a ( Figure 7 In some embodiments, the system may be configured to determine an infrared reflectivity associated with the semiconductor device based on the detected first radiation sample.

[0159] At operation 1104, the system detects a second radiation sample associated with the plurality of infrared bands. The second radiation sample may be based on a second infrared radiation source 710b ( Figure 7 ). The second infrared radiation source 710b can be positioned on an opposite side of the semiconductor device. The second modulation frequency can be different from the first modulation frequency. The second radiation sample can be based on infrared radiation that penetrates and transmits through the semiconductor device. In this example, the system can determine an infrared transmittance associated with the semiconductor device based on the second radiation sample.

[0160] In this example, the second infrared radiation source 710b may emit radiation toward an opposite side of the semiconductor device at a modulation frequency that is different from the modulation frequency of the radiation emitted by the first infrared radiation source 710a.

[0161] At operation 1106, the system may determine a dopant profile property associated with the semiconductor device based on the first radiation sample and the second radiation sample. The dopant profile property may be based on at least one of (i) infrared reflectivity determined based on the detected first radiation sample and (ii) infrared transmittance determined based on the detected second radiation sample.

[0162] exist Figure 11 In method 1100, although the system can detect the first radiation sample and the second radiation sample without advancing the positioning of the semiconductor device relative to the radiation source device or the radiation detector, in some embodiments, the system can advance the positioning of the semiconductor device under test so that multiple first radiation sample / second radiation sample groups can be obtained to determine the dopant distribution properties based on data readings at multiple locations across the surface of the semiconductor device under test.

[0163] In some embodiments, an infrared detection device or radiation detector may include one or more radiation sensors, a processor coupled to the one or more radiation sensors, and a memory storing processor-executable instructions that, when executed, configure the processor to perform Figure 10 Method 1000 or Figure 11 One or more operations in method 1100.

[0164] A radiation detector can be used for contactless characterization of a semiconductor device that can be housed between a radiation guiding device and an infrared radiation source. The radiation detector can be located proximal to the infrared radiation source, and the infrared radiation source can emit radiation toward the semiconductor device. The processor can perform operations to configure the radiation detector to sense radiation associated with a plurality of infrared bands from the semiconductor device to determine the dopant distribution properties of the semiconductor device. As disclosed in the examples herein, the sensed radiation can include radiation reflected from the semiconductor device originating from the infrared radiation source. The sensed radiation can include radiation originating from the radiation guiding device and penetrating the semiconductor device and emitted from the semiconductor device. The radiation guiding device can be located proximal to the infrared radiation source and configured to guide radiation toward the side opposite to the semiconductor side. The processor can be configured to determine the dopant distribution properties based on at least one of the infrared reflectivity or the infrared transmittance associated with the plurality of corresponding infrared bands.

[0165] In some embodiments, a processor may be coupled to or integrated with the radiation detector and may execute processor-executable instructions for determining a dopant profile property based on infrared reflectivity or transmittance associated with the semiconductor device under test.

[0166] refer to Figure 12 , which shows a block diagram of a computing device 1200 according to an embodiment of the present disclosure. As a non-limiting example, FIG. Figure 7 The infrared detection devices 412 and 712 can be used Figure 12 The example computing device 1200 is implemented as shown in FIG.

[0167] Computing device 1200 includes at least one processor 1202 , memory 1204 , at least one I / O interface 1206 , and at least one radiation sensor 1208 .

[0168] The processor 1202 may be a microprocessor or microcontroller, a digital signal processing processor, an integrated circuit, a field programmable gate array (FPGA), a reconfigurable processor, or a programmable read-only memory (PROM).

[0169] The memory 1204 may include an internal or external computer memory such as random access memory, read-only memory, optical disk read-only memory, electro-optical memory, magneto-optical memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, or ferroelectric RAM.

[0170] The memory 1204 may contain processor-readable instructions that, when executed, configure the processor to perform the operations disclosed in this disclosure.

[0171] I / O interface 1206 may enable computing device 1200 to interconnect with one or more infrared radiation source devices, such as infrared radiation source 410 , first infrared radiation source 710 a , or second infrared radiation source 710 b of FIG. 4 , or other devices of a system for non-contact characterization of semiconductor devices.

[0172] by Figure 7 Taking the system 700 as an example, the computing device 1200 can be interconnected with the first infrared radiation source 710a and the second infrared radiation source 710b, and can transmit a signal for controlling the modulation frequency of the infrared signals emitted from the corresponding infrared radiation sources.

[0173] The at least one radiation sensor 1208 may be one or more sensors configured and positioned to receive a radiation signal reflected from or transmitted through the semiconductor device under test.

[0174] In some embodiments, the one or more sensors may be positioned in combination with a bandpass filter or other device to determine the portion of the radiant energy used to determine infrared transmittance, infrared reflectance, or other signal characteristics associated with the semiconductor device under test.

[0175] The terms “connected” or “coupled to” may include both direct coupling (where two elements being coupled to each other are in contact with each other) and indirect coupling (where at least one additional element is located between the two elements).

[0176] Although various embodiments have been described in detail, it should be understood that various changes, substitutions, and alterations may be made herein without departing from the scope. Furthermore, the scope of the present disclosure is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods, and steps described in this specification.

[0177] As will be readily apparent to one skilled in the art from this disclosure, currently existing or later to be developed processes, machines, manufacture, compositions of matter, means, methods, or steps may be utilized that perform substantially the same function or achieve substantially the same results as those in the corresponding embodiments described herein. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

[0178] This description provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to encompass all possible combinations of the disclosed elements. Thus, if one embodiment includes elements A, B, and C, and a second embodiment includes elements B and D, then the inventive subject matter is considered to encompass other remaining combinations of A, B, C, or D, even if not explicitly disclosed.

[0179] The various embodiments of the apparatus, system, and method described herein can be implemented in a combination of hardware and software. These embodiments can be implemented on programmable computers, each of which includes at least one processor, a data storage system (including volatile memory or non-volatile memory or other data storage elements or a combination thereof), and at least one communication interface.

[0180] Program code is applied to input data to perform the functions described herein and to generate output information. The output information is applied to one or more output devices. In some embodiments, the communication interface can be a network communication interface. In various embodiments in which components can be combined, the communication interface can be a software communication interface, such as those used for inter-process communication. In still other embodiments, the combination of communication interfaces can be implemented as hardware, software, and combinations thereof.

[0181] Throughout the foregoing discussion, numerous references have been made to servers, services, interfaces, portals, platforms, or other systems formed by computing devices. It should be understood that the use of such terms is considered to refer to one or more computing devices having at least one processor configured to execute software instructions stored on a computer-readable, tangible, non-transitory medium. For example, a server may include one or more computers operating as a web server, database server, or other type of computer server to fulfill the described roles, responsibilities, or functions.

[0182] The technical solutions of each embodiment may take the form of a software product. The software product may be stored in a non-volatile or non-transitory storage medium, such as a compact disc read-only memory (CD-ROM), a USB flash drive, or a removable hard drive. The software product contains a plurality of instructions that enable a computer device (a personal computer, a server, or a network device) to execute the methods provided by each embodiment.

[0183] The embodiments described herein are implemented by physical computer hardware, including computing devices, servers, receivers, transmitters, processors, memory, displays, and networks. The embodiments described herein provide useful physical machines and computer hardware arrangements of specific configurations.

[0184] It will be understood that the examples described and illustrated above are intended to be exemplary only.

Claims

1. A system for non-contact characterization of a semiconductor device under test, the system comprising: an infrared radiation source that directs radiation toward the semiconductor device; a radiation guiding device positioned proximate the infrared radiation source and configured to guide radiation toward an opposite side of the semiconductor device, the semiconductor device being receivable between the radiation guiding device and the infrared radiation source; as well as a radiation detector located proximate to the infrared radiation source and configured to sense radiation associated with a plurality of infrared bands from the semiconductor device to determine a dopant distribution property of the semiconductor device, the sensed radiation including radiation originating from the infrared radiation source and reflected from the semiconductor device, and the sensed radiation including radiation originating from the radiation guiding device and emitted from the semiconductor device, The dopant distribution property is based on at least one of infrared reflectivity or infrared transmittance associated with the corresponding plurality of infrared bands.

2. The system of claim 1 , wherein the radiation guiding device is a supplemental radiation source that emits radiation toward and penetrates the semiconductor device, And wherein a portion of the radiation that penetrates the semiconductor device is detected by the radiation detector to determine an infrared transmittance associated with the semiconductor device.

3. The system of claim 2 , wherein the supplemental radiation source and the infrared radiation source direct radiation from opposite sides toward the semiconductor device at different modulation frequencies, respectively. And wherein the radiation detector demodulates the sensed radiation from the semiconductor device to determine infrared reflectivity or infrared transmittance.

4. The system of claim 1 , wherein the radiation-directing device comprises a paddle configured to convey the semiconductor device proximal to the infrared radiation source and the radiation-directing device, Wherein the paddle includes a high reflectivity background that reflects radiation toward the semiconductor device, the reflected radiation being based on radiation emitted from the infrared radiation source.

5. The system of claim 4, wherein the high reflectivity background comprises at least one of aluminum or gold.

6. The system of claim 4, wherein the paddle comprises a low reflectivity background positioned adjacent to the high reflectivity background, wherein the low reflectivity background comprises at least one of an optically opaque material or an aperture through which incident radiation passes.

7. The system of claim 6, wherein the low reflectivity background is associated with a first sensing location and the high reflectivity background is associated with a second sensing location, radiation from the infrared radiation source being emitted toward the first sensing location and the second sensing location. 8 . The system of claim 7 , wherein a separation distance between the first sensing location and the second sensing location is based on an expected spatial uniformity of the semiconductor device under test.

9. The system of claim 7 , wherein the radiation detector is configured to sense reflected radiation from the semiconductor device to determine infrared reflectivity in response to radiation emitted from the infrared radiation source toward the first sensing location. And wherein in response to radiation emitted from the infrared radiation source toward the second sensing location, the radiation detector is configured to sense radiation reflected from the radiation guiding device and transmitted through the semiconductor device to determine infrared transmittance. 10 . The system of claim 9 , wherein the paddle is configured to transfer the semiconductor device from the first sensing location to the second sensing location or from the second sensing location to the first sensing location.

11. The system of claim 1 , wherein the plurality of wavelength bands are along a wavelength spectrum from 1.2 μM to 20 μM. 12 . The system of claim 11 , wherein at least one of the plurality of wavelength bands overlaps with an adjacent wavelength band in the wavelength band spectrum of 1.2 μM to 20 μM.

13. The system of claim 1, wherein the dopant profile property of the semiconductor device comprises sheet resistance or dopant surface concentration.

14. A method for non-contact characterization of a semiconductor device, the method comprising: detecting a first radiation sample associated with a plurality of infrared bands from a first location, the first radiation sample comprising radiation originating from an infrared radiation source and reflected from a first side of the semiconductor device; detecting a second radiation sample associated with the plurality of infrared bands, the second radiation sample comprising radiation originating from a radiation directing device positioned on an opposite side of the semiconductor device, the second radiation sample being based on radiation exiting the first side of the semiconductor device; as well as A dopant profile property associated with the semiconductor device is determined based on at least one of infrared reflectivity determined based on the detected first radiation sample or infrared transmittance determined based on the detected second radiation sample.

15. The method of claim 14, wherein the radiation guiding means comprises a reflective paddle having a low reflectivity portion and a high reflectivity portion, wherein the first radiation sample is detected when infrared radiation is directed toward a first location of the semiconductor device adjacent to the low reflectivity background, And wherein the second radiation sample is detected when infrared radiation is directed toward a second location of the semiconductor device adjacent to the high reflectivity background.

16. The method according to claim 15, comprising: positioning the reflective paddle to direct infrared radiation from the infrared radiation source toward the first location of the semiconductor device adjacent the low reflectivity background; as well as The reflective paddle is positioned to direct infrared radiation from the infrared radiation source toward the second location of the semiconductor device adjacent the high reflectivity background in response to detecting the first radiation sample.

17. The method of claim 15, wherein a separation distance between the first location and the second location is based on an expected spatial uniformity of the semiconductor device under test.

18. The method of claim 14, wherein the radiation guiding device comprises a supplemental radiation source that emits radiation toward and through the semiconductor device, And wherein the second radiation sample is based on radiation originating from the supplemental radiation source and exiting from the first side of the semiconductor device for determining infrared transmittance associated with the semiconductor device.

19. The method of claim 18, wherein the infrared radiation source and the supplemental radiation source each emit infrared light at a different modulation frequency, and wherein the method includes demodulating the first radiation sample and the second radiation sample.

20. The method of claim 14, wherein the plurality of infrared bands comprises bands along the spectrum from 1.2 μM to 20 μM.

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