Quasi-in-situ X-ray photoelectron spectroscopy analysis method for environmental failure of thin film semiconductor material

Abstract

The invention relates to the technical field of thin film semiconductor material analysis, and particularly discloses a quasi-in-situ X-ray photoelectron spectroscopy analysis method for environmental failure of a thin film semiconductor material. The method comprises the following steps: performing a failure environment simulation test on a sample by using an XPS in-situ illumination system and / or an XPS quasi-in-situ high-temperature gas reaction system; analyzing real-time / quasi-real-time surface chemical information of the sample in the environmental failure simulation process by using a surface analysis technology, and obtaining change rules of surface components, chemical states, electronic structures and interface structures of the sample; based on analysis of change rules of surface components, chemical states, electronic structures and interface structures of the samples, the failure mechanism of the samples under the action of the failure environment is obtained. The method aims at solving the problem that a traditional failure analysis method cannot analyze change rules of surface components, chemical states, electronic structures and interface structures in the failure process, and then basic technical support is provided for sample failure mode and failure mechanism analysis and sample design improvement.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of thin film semiconductor material analysis, and particularly relates to a kind of thin film semiconductor material environmental failure quasi in-situ X-ray photoelectron spectroscopy analysis method. BACKGROUND

[0002] The application of thin film semiconductor material covers all electronic devices and equipment of equipment industry, with the high-speed development of space technology, it is also widely used in space, aircraft devices micro electro mechanical system, such as relay, brake, radio frequency circuit and hybrid switch form exists micro intelligent integrated system. During use and storage, the sample will cause the aging of its own material, corrosion and internal stress change due to the natural environmental factors (temperature, humidity, salt spray, precipitation, mold, sand dust, etc.) and induced environmental factors (mechanical factors, current, radiation effect, etc.) experienced by the sample, causing the performance degradation of the device even failure, leading to the reduction of electronic component use and storage reliability. The failure mode of thin film semiconductor material and device can be roughly divided into thermal overstress failure, electrical overstress failure, chip failure, packaging failure and other failures. Among them, thermal overstress failure and electrical overstress failure are the main failure modes of thin film semiconductor material and device. Thermal overstress can cause semiconductor failure, high temperature can melt metal material, carbonize plastic, warp, damage semiconductor chip, and cause other types of damage. The external cause of thermal stress of electronic components is the change of external temperature, which may come from two aspects: one is the change of the temperature of the working or storage environment of electronic components. For example, the temperature difference of the storage site of electronic components is large, which is equivalent to a slow temperature cycle test of electronic components; the second is the temperature change of electronic components during welding assembly, which causes the slow release of residual stress during storage and thus causes certain thermal stress of electronic components. At the same time, with the continuous reduction of the size of electronic components, some harsh service conditions are imposed on the material, such as high current intensity and high local temperature, which can also cause thermal overstress failure of the material as internal cause. Electrical overstress failure is mainly caused by electromigration of thin film during conduction, when current flows through the semiconductor film, electrons will collide with metal atoms, causing metal atoms to move, and thus causing vacancies and composition segregation in the semiconductor film. Under the influence of these specific failure modes and multiple failure modes coupling, thin film semiconductor material is prone to serious interdiffusion, which leads to significant changes in device performance, affecting the safe and normal operation of electronic systems and even the entire equipment system.

[0003] At present, the common micro evaluation method for the corrosion failure mechanism and corrosion failure protection of thin film semiconductor material at home and abroad is mainly to judge by measuring the macroscopic parameters of electrical properties and observing the surface morphology and composition by scanning electron microscopy. However, the macroscopic detection method of electrical properties is mostly used for the analysis after the corrosion failure occurs, and the evaluation method for this failure mostly stays at the macroscopic level, which is difficult to be used for the early analysis of failure; and the scanning electron microscopy can only observe the morphology after failure, which is lagging and difficult to understand the failure process, the chemical reaction in the early stage of failure and the expansion of failure products. The research results show that the early failure of the material is related to the surface morphology of the material, and also related to the surface composition and adsorption, segregation, diffusion and other surface phenomena and interface conditions. In fact, the early failure basically occurs in the depth range of tens to hundreds of nanometers of the surface of the thin film semiconductor material and device, but the current failure evaluation method is mostly based on the measurement and analysis of macroscopic parameters, which is difficult to accurately analyze and judge the surface state of the material and device in the nanometer range. SUMMARY

[0004] The purpose of the present application is to provide a quasi-in-situ X-ray photoelectron spectroscopy analysis method for environmental failure of thin film semiconductor material, aiming to solve the problem that the traditional failure analysis method cannot analyze the micro composition and chemical state change of the failure process, and to provide basic technical support for failure mode analysis, failure mechanism analysis and sample design improvement.

[0005] To achieve this purpose, the present application adopts the following technical solutions: A quasi-in-situ X-ray photoelectron spectroscopy analysis method for environmental failure of thin film semiconductor material, the method comprising the following steps: Using an XPS in-situ light system and / or an XPS quasi-in-situ high temperature gas reaction system to perform a failure environment simulation test on the sample; Using surface analysis technology to analyze the real-time / quasi-real-time surface chemical information of the sample during the failure environment simulation test, and obtaining the surface composition, chemical state, electronic structure and interface structure change rule of the sample; Based on the analysis of the surface composition, chemical state, electronic structure and interface structure change rule of the sample, the failure mechanism of the sample under the failure environment is obtained.

[0006] Preferably, the step of using surface analysis technology to analyze the real-time / quasi-real-time surface chemical information of the sample during the failure environment simulation test comprises: using an X-ray photoelectron spectrometer to analyze the sample; The XPS in-situ light irradiation system is integrated in the analysis chamber of the X-ray photoelectron spectrometer, the XPS quasi-in-situ high-temperature gas reaction system is in vacuum communication with the analysis chamber of the X-ray photoelectron spectrometer, and the sample is transferred between the analysis chamber of the X-ray photoelectron spectrometer and the processing chamber of the XPS quasi-in-situ high-temperature gas reaction system through a vacuum transfer sample holder.

[0007] Preferably, the analysis of the sample by the X-ray photoelectron spectrometer comprises: analyzing the surface composition distribution, the surface chemical state, the surface electronic state and the electronic band structure of the sample; analyzing the atomic diffusion in the sample, the interface composition distribution and the interface reaction product.

[0008] Preferably, the failure environment simulation test of the sample by the XPS in-situ light irradiation system comprises ultraviolet light irradiation test and visible light irradiation test.

[0009] Preferably, the failure environment simulation test of the sample by the XPS quasi-in-situ high-temperature gas reaction system comprises heating treatment, environmental atmosphere reaction treatment and direct current treatment.

[0010] Preferably, before the failure environment simulation test of the sample, the sample without appearance quality defects is screened based on the surface chemical information analysis result of the sample before the failure environment effect.

[0011] Preferably, the method further comprises: checking whether the sample after the failure environment effect is failed, and preliminarily judging the failure mode.

[0012] The present application has the following advantages: 1. The present application is a systematic and comprehensive environmental failure analysis method, which can effectively analyze the potential failure of various thin film semiconductor material devices, has strong applicability, and has wide application range.

[0013] 2. The present application can complete customized failure conditions and environments according to the actual environment used by the finished device or the test stress requirement in the design process of the device, is flexible and diverse, has strong adaptability, and is highly operable. Moreover, the external stress applying device and the X-ray photoelectron spectrometer are in vacuum communication, the device can exclude the interference of other factors in the external stress applying process, realizes quasi-in-situ analysis and detection, and has stronger guidance and higher accuracy in analyzing the failure mechanism.

[0014] 3. The application can provide strong support for improving device reliability, has incomparable advantages in studying device environmental failure mechanism, can analyze potential defects more comprehensively and deeply before a large number of finished devices are put into use, and can be used for targeted test research in the device design process, thereby shortening the device design and development cycle and reducing the research and development cost. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a flow block diagram of a sample environmental failure mechanism analysis method provided by an embodiment of the application.

[0016] Figure 2 is a sample environmental failure mechanism analysis flowchart of a thin-film semiconductor material environmental failure quasi-in-situ X-ray photoelectron spectroscopy analysis method provided by an embodiment of the application. DETAILED DESCRIPTION

[0017] The technical solutions of the application are further illustrated below with reference to the drawings and specific embodiments.

[0018] As shown in Figure 1 and 2 , a thin-film semiconductor material environmental failure quasi-in-situ X-ray photoelectron spectroscopy analysis method comprises the following steps S1-S3.

[0019] S1: Using an XPS in-situ light irradiation system and / or an XPS quasi-in-situ high-temperature gas reaction system to perform a failure environment simulation test on the sample.

[0020] In an embodiment of the application, a thin film can be prepared on a semiconductor material by a thin film preparation method such as magnetron sputtering, wherein the process parameters (such as sputtering power, sputtering pressure, sputtering time, target-to-substrate distance, etc.) in the magnetron sputtering process can be regulated according to the target thickness of the thin film. In addition, a thin film can also be prepared on a semiconductor material by other thin film preparation methods such as vacuum evaporation, pulsed laser deposition, molecular beam epitaxy, etc. After the thin film is prepared, the semiconductor material with the thin film can be sliced and sampled by a scribe machine, and cut into a single sample with an area size of 10 mm x 6 mm.

[0021] In an embodiment of the application, the XPS in-situ light irradiation system is integrated in the analysis chamber of the X-ray photoelectron spectrometer, and the processing chamber of the XPS quasi-in-situ high-temperature gas reaction system is in vacuum communication with the analysis chamber of the X-ray photoelectron spectrometer. The sample is moved between the processing chamber of the XPS quasi-in-situ high-temperature gas reaction system and the analysis chamber of the X-ray photoelectron spectrometer by a vacuum transfer sample holder.

[0022] In one embodiment of the present application, the XPS in-situ light irradiation system can be used to perform light irradiation failure environment simulation tests such as ultraviolet irradiation tests and visible light irradiation tests; the XPS quasi-in-situ high-temperature gas reaction system can be used to perform failure environment simulation tests such as heating treatment, environmental atmosphere reaction treatment, and direct current treatment. For example, to study the influence of ultraviolet irradiation in outer space environment on thin film semiconductor devices for aerospace, the sample is subjected to ultraviolet irradiation, and the influence of different irradiation intensities and times on the surface electronic structure, surface composition distribution, and surface chemical state is studied; to study the influence of thermal effects on the device, the device is subjected to heating treatment, and the influence of temperature on the element valence and composition distribution along the depth of the sample in different environmental atmospheres is studied.

[0023] In addition, more devices (such as humidification devices and salt spray generation devices) interconnected with the X-ray photoelectron spectrometer can be added to realize simulation of multiple types of environmental failure factors.

[0024] S2: The surface chemical information of the sample in the failure environment simulation test process is analyzed in real time / quasi-real time by using surface analysis technology, and the surface composition, chemical state, electronic structure, and interface structure change rule of the sample are obtained.

[0025] The surface chemical information of the sample in the failure environment simulation test process is analyzed in real time / quasi-real time by using surface analysis technology, and the surface composition, chemical state, electronic structure, and interface structure change rule of the sample are obtained.

[0026] Further, the analysis of the sample by using the X-ray photoelectron spectrometer includes analyzing the surface composition distribution, surface chemical state, and surface electronic state of the sample; analyzing the electronic energy band structure of the sample by using ultraviolet photoelectron spectroscopy (UPS) and inverse photoelectron spectroscopy (IPES); and analyzing the atomic diffusion, interface composition distribution, and interface reaction product inside the sample by using angle-resolved depth analysis method and ion etching depth analysis method.

[0027] In one embodiment of the present application, the sample with no quality defects such as pinholes, burrs, islands, cracks, and silicon dust in appearance can be first screened out based on the surface chemical information analysis results of the surface composition, chemical state, electronic structure, and interface structure of the sample before the failure environment action, and then the screened sample is subjected to the failure environment simulation test.

[0028] In one embodiment of the present application, after the sample is taken out from the X-ray photoelectron spectrometer, it can be checked whether the sample fails after the failure environment action, and the failure mode is preliminarily judged.

[0029] S3: Based on the analysis of the surface composition, chemical state, electronic structure, and interface structure change rule of the sample, the failure mechanism of the sample under the failure environment action is obtained.

[0030] The scheme of the present application is further illustrated below by specific examples.

[0031] The Au / Ni / Cu / HfO2 thin film semiconductor material is taken as the research object, and the physical and chemical adsorption caused by directly exposing the sample to air after the conventional environmental failure treatment is not conducive to the semi-quantitative and qualitative analysis of the surface O element; especially when the bulk Cu atoms diffuse to the sample surface, the Cu atoms are prone to react with atmospheric oxygen and water vapor, and the real valence information cannot be obtained by XPS analysis. The present application combines the quasi-in-situ high-temperature gas reaction system with the quasi-in-situ XPS analysis technology, analyzes the change rule of the surface composition of the material by heating and respectively introducing oxygen and nitrogen, and analyzes the relative atomic concentration ratio of the O element, the Cu element and the Ni element on the surface to the concentration of the Au element on the surface. The quasi-in-situ X-ray photoelectron spectroscopy analysis method of the present application can accurately analyze the real-time composition and valence information of the elements on the surface of the sample, and further accurately study the influence mechanism of the adsorbed oxygen on the film layer structure, so as to reveal the diffusion mechanism.

[0032] The quasi-in-situ X-ray photoelectron spectroscopy analysis method of the thin film semiconductor material environmental failure of the present application can systematically and comprehensively analyze the potential failure of various thin film semiconductor material devices, has strong applicability, wide application range, and can be customized according to the actual environment of the finished device or the test stress requirement in the design process of the device. The failure conditions and environment are flexible, diverse, adaptable and highly operable. Moreover, the external stress applying device and the X-ray photoelectron spectrometer are connected in vacuum, the device can be free from interference of other external factors during the external stress applying process, quasi-in-situ analysis and detection are realized, the analysis of the failure mechanism is more instructive and accurate.

[0033] In addition, the present application can provide strong support for improving the reliability of the device, has incomparable advantages in studying the environmental failure mechanism of the device, can analyze and find potential defects and improve the device before a large number of finished devices are put into use. In addition, the method can be used for targeted test research during the design process of the device, so as to shorten the design and development cycle of the device and reduce the research and development cost.

[0034] The technical principles of the present application are described above in combination with specific examples. These descriptions are only for explaining the principles of the present application, and cannot be explained as limiting the protection scope of the present application in any way. Based on the explanations herein, other specific embodiments of the present application can be conceived by those skilled in the art without creative labor, and these embodiments will fall within the protection scope of the present application.

Claims

1. A quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials, characterized in that, The method includes the following steps: Failure environment simulation tests were conducted on the samples using an XPS in-situ illumination system and / or an XPS quasi-in-situ high-temperature gas reaction system. Surface analysis techniques are used to analyze the real-time / near real-time surface chemical information of samples during failure environment simulation tests, and to obtain the changes in surface composition, chemical state, electronic structure and interface structure of the samples. Based on the analysis of the changes in surface composition, chemical state, electronic structure and interface structure of the samples, the failure mechanism of the samples under the action of the failure environment is obtained.

2. The quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials according to claim 1, characterized in that, The analysis of the surface chemical information of the sample in real-time / quasi-real-time during the failure environment simulation test using surface analysis technology includes: in-situ / quasi-in-situ analysis of the sample using X-ray photoelectron spectroscopy; The XPS in-situ irradiation system is integrated into the analysis chamber of the X-ray photoelectron spectrometer. The XPS quasi-in-situ high-temperature gas reaction system is in vacuum communication with the analysis chamber of the X-ray photoelectron spectrometer. The sample is transferred between the analysis chamber of the X-ray photoelectron spectrometer and the processing chamber of the XPS quasi-in-situ high-temperature gas reaction system via a vacuum transfer sample holder.

3. The quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials according to claim 2, characterized in that, The analysis of the sample using X-ray photoelectron spectroscopy includes: The surface composition distribution, surface chemical state, surface electronic state, and electronic band structure of the samples were analyzed. The atomic diffusion, interfacial composition distribution, and interfacial reaction products within the sample were analyzed.

4. The quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials according to claim 1, characterized in that, Failure environment simulation tests on samples using the XPS in-situ irradiation system include ultraviolet irradiation tests and visible light irradiation tests.

5. The quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials according to claim 1, characterized in that, The failure environment simulation test of the sample using the XPS quasi-in-situ high-temperature gas reaction system includes heating treatment, ambient atmosphere reaction treatment, and direct current treatment.

6. The quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials according to claim 1, characterized in that, Before conducting failure environment simulation tests on the samples, samples without appearance defects are selected based on the surface chemical information analysis results of the samples before the failure environment.

7. The quasi-in-situ X-ray photoelectron spectroscopy method for environmental failure of thin-film semiconductor materials according to claim 1, characterized in that, The method further includes: checking whether the sample has failed after being subjected to the failure environment, and making a preliminary judgment on the failure mode.

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