TW200411167A - Detection method and apparatus - Google Patents

Abstract

A method of quality control of structures of semiconductors such as silicon prior to device fabrication thereupon comprises exposing the surface of a semiconductor structure under test to at least one high-intensity beam of light from a suitable light source, preferably a laser, and in particular a high- intensity laser, and collecting photoluminescence (PL) produced by excitation of the semiconductor structure by the light beam; numerically analysing the photoluminescence emitted across the area of the structure; comparing the result with a predetermined acceptable specification range of photoluminescence; making a quality classification of the semiconductor structure based thereon, and in particular rejecting or selecting for remedial action semiconductor structures exhibiting a photoluminescence response outside the said predetermined acceptable specification range. In a preferred embodiment the method is applied as part of a quality control metric prior to device fabrication. In a refinement of the method a spatially resolved PL map is also collected. An apparatus for performing the method is also described.

Description

200411167 (1) Description of the invention: [Technical field to which the invention belongs] The present invention relates to a method for detecting surface layer metal contamination and other defects in a semiconductor structure (such as silicon), especially for detecting components before semiconductor manufacturing. Non-destructive methods and devices for testing defects in supplied parent materials, such as semiconductor wafers. In particular, the present invention is to provide an improved semiconductor material quality control system prior to an amount of product is applied to the element producing the supplied. [Previous Technology] Over the past 50 years, the progress made in silicon technology has produced significant improvements in chip performance, and these advances have also brought about rapid growth in silicon technology. The ability of the semiconductor device industry to make progress by reducing the cost of each device function by about 30% per year has become a key factor for its rapid growth. To maintain this trend, the geometry of components has been reduced to a point where the number of transistors that can be included on a single wafer has increased to 5 million. As a result, this has brought more requirements for the material properties of starting semiconductor materials. . The introduction of parent materials such as wafers (ground and epitaxial wafers) may contain a range of defects. I acknowledge that the control of these defects in the raw materials is the key factor to achieve the high 1C yield of the components manufactured on the material (International Semiconductor Roadmap 2001, SEMATECH, 3101 Industrial Terrace Suite 106, Austin TX 78758) . Defects include both surface chemical residues (such as organics and transition metals) and grown-in microscopic defects. Similarly, also must be controlled junction on the epitaxial wafer

86767.DOC 200411167 structural defects, such as epitaxial stacking defects and other large area defects. Removal and prevention of surface defects are a challenge to the current state of the art in ♦ and other semiconductor crystal technology. See also Silicon-on-insulator wafers are also used in Sl component manufacturing; these wafers offer potential for high-speed and low-power applications. In order to characterize these wafers to determine the performance of the SOI material and how it affects subsequent device performance. At first, in order to further process the development necessary to achieve the economies of scale required for large-volume IC manufacturing, the production of larger 300mm diameter wafers is increasing (expected to increase by 7% in 2002). Key metrology mechanisms are needed to measure defects and metal contamination on large-area wafers with higher sensitivity, and at the same time to develop detection methods that can give information about the spatial distribution of defects and contamination. The use of a 300mm starting wafer also promotes the use of recycled wafers (wafers that have been recycled and reused and recleaned) as the use of recycled wafers will be reduced from 200mm to 300mm. Total cost of the millimeter wafer transition. However, in some applications, we are reluctant to use recycled wafers because these wafers may contain high surface metal contamination due to incomplete surface cleaning. Again, a method that can accurately characterize defects on all such wafers would be of great benefit. The standard method for measuring metal contamination on the surface is total reflection fluorescent fluorescence analysis (TXRF). This technique determines the type of pollution and its concentration. However, this technology does not allow for wafer mapping capabilities. A typical measurement only covers 丨 cm2 and takes about an hour. As a result, in practice, usually from the wafer center

86767.DOC 200411167 Performs a single measurement. This technology cannot actually provide information related to the spatial distribution of contamination throughout the wafer area in actual timescales. At the same time, the technology is usually based outside the clean room area and due to enhanced demand, it takes time to obtain results. For all of the above reasons, the prior art is usually limited to representative batch sampling, because time stamping does not allow testing of units in a given batch. SUMMARY OF THE INVENTION An object of the present invention is to provide a method and a device for quality control of a semiconductor (such as chipping) by detecting surface layer body metal contamination and other defects in a structure before the element is manufactured, the method and the device reduce Some or all of the above disadvantages. The present invention provides a method and an apparatus for a specific purpose to perform component manufacturing on a parent material, and to provide a faster evaluation of the quality of a supplied parent material such as a semiconductor wafer. A specific object of the present invention is to provide a method and device for quality evaluation. The method and device provide a higher output rate, and in particular, achieve a quality control metric that can be used in component manufacturing. Testing of all incoming parent materials was previously achieved. / Therefore, according to the first aspect of the present invention, a method for quality control of a semiconductor structure (such as chipping) before the fabrication of semiconductor components on a semiconductor structure includes the following steps: For at least one week, at least one high-intensity beam of a source (preferably laser ', especially a high-intensity laser) is collected, and the light generated by exciting the semiconductor structure by the beam is collected to

86767.DOC L67 Light (pL); proud of the collected light is used as the basis for the quality classification of this analysis r σ 6 for the component manufacturing. The number = grading step includes: performing a knife on the collected photoluminescence signal, combining the results of the silk value analysis with a predetermined acceptable photoluminescence specification, such as my own knowledge of milk / people know about good products f The photoluminescence predetermined range and the tritium comparison are made, and the quality classification of the semiconductor structure is made based on the comparison. In a simple alternative method, the method includes the steps of: determining an average photoluminescence intensity; comparing the average value with a predetermined acceptable specification range of photoluminescence; and making a comparison based on the comparison as described above The quality of the body structure is graded. The average value may be an entire area average based on the average photoluminescence intensity emitted by the entire structure area, or may be a local area average, in which the structure area is divided into sub-areas of a two-dimensional array, and the average is determined for each sub-area. Photoluminescence intensity, the average value of each sub-region is compared with a predetermined acceptable photoluminescence specification, and the quality classification as described above is based on the Tibetan comparison. This approach is advantageous because a response to a single defect can be buried in an entire regional average, even if the defect is severe enough to identify a defective product. With an appropriate sub-region size, it is ensured that the response can still be detected. The use of a predetermined photoluminescence specification based on the average value is just one example. In this alternative method, especially when using the sub-area method, other numerical parameters, such as standard deviation, local maximum and / or minimum, deviation from a pre-filled baseline, or other numerical analysis methods may be applied to the photoinduced In the analysis of the luminous signal, the deviation between the photoluminescence response of 86767.DOC -10- 200411167 and the predetermined parameters is determined on the basis of the local or the entire area. We know that the predetermined parameters are related to a semiconductor of good quality. structure. In the following, reference is made to numerical analysis based on average luminescence, which should be understood as an example only, and the precise numerical parameters selected to compare the observed response with a predetermined acceptable response are not critical to the present invention. Compared with the TXRF technology in the prior art, the photoluminescence technology can generate a quick response. It takes samples throughout the entire wafer area, and produces an average result based on the entire wafer, and therefore is more representative of the condition of the entire wafer than TXRF technology, which actually focuses on sampling in a specific, arbitrary sample area. The speed and accuracy of this technology make it a more effective and practical quality control method than previous technologies. In particular, it ’s possible to test all attractive semiconductor infrastructures before manufacturing. This feature achieves greatly improved quality control, and enables accurate screening of reclaimed wafer structures and wafers in new manufacturing states (and thus enhances the possibility of using such wafers). Therefore, in another preferred aspect, the present invention includes a quality control metric for the fabrication of semiconductor devices on semiconductor structures that induces semiconductive structures (cuts). This metric is incorporated into the component manufacturing process. -Part, which includes the following steps: according to the aforementioned aspect of the present invention, successively test a series of attractive structures; the structure of the photoluminescence response within the range of acceptable specifications of the phosphorescent light will be displayed Pass to the next — = segment; exclude the photoluminescence response structure outside the predetermined acceptable specification range of photoluminescence from the next manufacturing stage. Preferably 'pass the excluded structure for other measures, such as scrap

86767.DOC -11-200411167 or (for example) hunting corrective treatment by cleaning. After that, it is convenient to carry out retesting and receiving / removing tasks such as heavy delay. An additional predetermined range of photoluminescence parameters can be determined and used to make additional determinations on the excluded structure. For example, a range can be identified (especially the photoluminescence level is at and / or below their acceptable specification range), in which corrective measures can be subsequently taken and can be immediately discarded or even Structures outside the wall. According to this preferred aspect, all structures are tested before the component is manufactured. Potentially inert products can be identified earlier before expensive manufacturing processes). Since the method of the present invention can produce accurate diagnosis before component manufacturing in a fast and convenient manner, and can be reliably discarded or disposed of with poor quality "maternal semiconductor structure, the number of inevitable defective products at the end of manufacturing should be decrease very much. Under the resolution of the characteristics of the high-intensity light beam, the photoluminescence technology produces a spatially resolved PL map. The pan-features can be utilized by another preferred feature of this method, but for the basic purpose of the present invention as a simple and fast quality test of the entire wafer during processing, it is only necessary to obtain it over the entire wafer area The average PL intensity results are linked to a predetermined range of acceptable specifications developed by a research institute that uses slower analytical methods such as TXRF. I was surprised to find that: The detailed description below shows a close correlation between the near-surface-based PL technology of the present invention and the defect data obtained from the conventionally used prior art method. Control the beam 'and especially the beam power and / or wavelength and / 86767.DOC -12- 200411167 or spot size to distinguish defects and contamination at a selected depth in the semiconductor structure, from a suitable classification ; ,, Hollow A ,,,,,, w Near surface / woodiness (such as 12 microns from the top of the semiconductor structure) to collect PL information. For certain materials and components, smaller depths, such as 5 micrometers or even micrometers, may be appropriate: 'The present invention-a defect monitoring tool, which can be used to monitor surface and other surface structural defects, such as overlapping Layer defects with edge slip. Since the surface area measurement technique, so it will accurately detect near surface defects and contamination. These defects are very decisive in their impact on component quality and performance. This further enhances the accuracy and reliability of the technology. According to the present invention, the first measuring predetermined acceptable specification range of photoluminescence average, and then use it as a reference to any given result wafers to achieve the purpose of quality control. The predetermined range of specifications will include a minimum and / or maximum value. In particular, we know that depending on the specific chemical contained in the impurity, the photoluminescence signal can be affected in different ways. Therefore, the range of specifications will preferably include a minimum and a maximum photoluminescence value. Depending whether the result of the measurement made within the predetermined range of specification products shellfish control determination, if within this range, the receiving structural elements manufactured for, and if outside this range, it is excluded. Discarded products can be discarded or subjected to corrective actions such as additional cleaning. The predetermined acceptable pL range will vary depending on the specific materials and processes involved, and by linking the PL response generated in accordance with the present invention with the response generated in accordance with the measurement techniques in existing prior art, The predetermined acceptable PL range is determined from the existing quality specification range. Once this range of specifications is established, the present invention provides

86767.DOC -13- 200411167 million law is a very high output. For example, for a 12-inch (2,00¾-meter) wafer, it will take about five minutes to obtain the results, while the existing method will take about one hour. Proluminescence (PL) spectroscopy is a very sensitive technique for observing internal and external electron transitions on impurities and defects in semiconductors. When high laser radiation in the material of (iv) in the material excited under low temperature, generating = electron hole pair. These «can cause luminescence in the same way as each material. Electron-hole pairs formed at low temperatures can be trapped on impurities in Shi Xi, and these electron-hole pairs emit photons with the characteristics of the interaction, thereby giving a heterof in the photoluminescence spectrum. Specific information. There are a large number of applied PL spectroscopy technologies, including the characterization of different processing steps, the characteristics of component manufacturing (such as implantation, oxidation, plasma etching, detection of point defect complexes, and the presence of dislocations). . One of the most important applications includes non-destructive measurement of shallow donors and acceptors such as arsenic, boron, and phosphorus. In particular, this technique enables the measurement of the concentration of such shallow donors and acceptors. However, in conventional applications, in order to obtain this spectral information of the optical center and clear chemical identification, measurement needs to be performed at the temperature of liquid helium. Throughout the semiconductor industry, it is known at room temperature for I, PL signal is significantly weakened and very little useful spectral taking available information. Thus the preferred temperature using techniques such as those described one particular non-destructive technique by the International Patent Application W098 / 11425, the reality-based detection technology makes the room temperature PL semiconductor structure in electrically active defects. The patent application discloses a PL technology with industrial applications. In its application, the technology can produce images in minutes, and the technology has another additional advantage of 86767.DOC -14- 200411167 points, which can be Produces a microscopic image of a small single defect, especially near the surface of the wafer on which the component is fabricated. This technology provides information about defects in a semiconductor or silicon structure at a rate suitable for industrial applications, and in particular enables us to visually inspect defects in the upper layers of the semiconductor or silicon structure, and especially near the surface of the structure. This technology uses enhanced non-radiative recombination of electron-hole pairs at defects in a semiconductor or silicon structure to enhance the contrast in one of the semiconductor or silicon structures' pL ~ image to enhance the observation of defects in the image. The preferred PL technology in W098 / 11425 is hereby incorporated by reference. The success of the room temperature PL method disclosed therein is partly due to the smaller, better spatial resolution of 0.1 to 20 microns, the more ideal range of 2 to 5 microns, and 104 to 109 watts per square. The detection capacity of laser detection for peak or average power density between centimeters, so local defects have a greater impact on the measured pL intensity, and I also believe that the success of this method is partly due to self-focusing excitation, The injected carrier has a higher density. This greatly increases the possibility of defects in the non-radiative recombination and thereby enhancing the physical positioning defects. Certain preferred defect described in more detail in the following examples, the present invention is prepared by a representative one of the PL response of the spatial mapping, and more preferably in a spatial image by using this method. Described herein contains the high intensity laser (not limitation) the high power density produced two shot 'i.e. the high power density laser, the laser power regardless of how big the radiation is focused. In a preferred method of the present invention, a pulsed laser excitation source is used, and ideally, the luminescence data is measured and / or the luminescence image is collected as time section 86767.DOC -15- 200411167 which means depth and space The resolution is improved and can be used to obtain information on the defect ' s capture section. You can also use time-resolved measurement to measure the effective carrier life and obtain a life map. The resolution of the mapping is not important. About 7 millimeters of resolution. At this level of resolution, the processing time is shortened and the test output rate is maximized. For example, it takes only five minutes to obtain a satisfactory acceptance / rejection result from a -12 shot (3 mm) wafer. The PL technology of the present invention generates a spatial analysis of the entire wafer area. In the present invention "Wang Yaowanfa, the data map is then processed to provide the average wafer level across the wafer, and the average & level Compare with benchmarks to make quality control decisions. If the method is used for simple acceptance and addition quality control judgments as a test before the structure is passed to the next manufacturing stage, only the average PL level need to be considered, and the method produced by this method, however, the comparison of the present invention One particular advantage of the good photoluminescence technology is: In addition, this technology can be used to generate a spatially resolved map of the PL signals running through the surface of the semiconductor structure under test, and in particular it can be used to generate spatially resolved images of these signals. This spatially resolved map was completely unachievable in the previous technique. Therefore, in a preferred embodiment, the method further includes a step of generating the mapping and / or the image. In these environments, mapping / imaging resolutions in millimeters or less may be appropriate. Conveniently, the method further comprises storing the spatially resolved PL map on an appropriate negative material storage component, and / or transmitting the digitized data obtained from the spatially resolved map for forward processing by an appropriate processing component, and / or The spatially resolved image is displayed on an appropriate display member. 86767.DOC -16- 200411167 This basic technology identifies an average PL intensity, and the acceptance / exclusion decision is based on this average PL intensity. Spatially parsed information is particularly useful when it comes to excluded structures. A better and more advanced quality control strategy may therefore use faster and more basic technologies to process each unit and generate only spatially resolved data for the excluded structures. In one embodiment, in order to fully utilize the technology to generate spatially resolved data 4 about the PL response of the semiconductor structure under test, it may be more appropriate (as indicated) to operate at a higher resolution. As a result, the output will be slower than just using this technology as the basis for accepting / excluding quality control decisions. A better and more advanced quality control strategy may therefore use the faster, more basic technology to process the units, and use the additional functionality provided by collecting spatially parsed data to reprocess the excluded structures at higher resolutions. The ability to generate maps or #images makes it possible to roughly identify the location of a defect. This feature is used in a preferred embodiment of the present invention. The method described above is used to quickly screen semiconductor structures (a wafer with a thickness of 3 mm only takes 5 minutes) and the cloud sample is completely chemically analyzed with it. An embodiment of the method includes subjecting a semiconductor to the tests described above to generate a spatially resolved map of the PL signal across the surface of the semiconductor structure, and using two analytical maps to identify the approximate extent of the contamination, at least in the case of excluded structures. And further analyze the semiconductor structure at the identified locations using a specific analysis technique such as TXRF to identify impurities. The pan method is applicable to any basic semiconductor structure on which components can be manufactured by heat treatment in a familiar manner. In particular, this method is applicable to structures based on silicon and silicon alloy < wafers. These elements can be made from simple single-layer crystals

86767.DOC -17-200411167 Round or made from multi-layer wafers to 0, such as epitaxial layers in a base silicon wafer. According to another aspect of the present invention, semi-conductors can be made ...: for the structural element comprises, intensity light source is preferably a laser, and in particular high strength = =, the children from a light source of high intensity beam is focused to two tests:;: member of a surface-collection member, It collects the surface of the semiconductor structure under test generated by the beam excitation II: 2 structure. Analysis of the knife member, which processes the collected and Numerical Analysis Information Section ': a comparator' which will analyze the results with a predetermined acceptable specification of parameters than the car qe 'and - configuration may be transmitted to the next stage of processing of transmission of a particular A component in which the transmission is determined based on whether the photoluminescence signal is within the predetermined acceptable specification range. , Japanese foot words, the transport member may show a structure of transmitted light within acceptable specifications Shu predetermined photoluminescence emission of the response to the electroluminescent element manufacturing stage, and will be displayed in the predetermined acceptable photoluminescence emission of the the outer structure of the transmission optical specifications electroluminescent response to (for example) or a disposal position correction processing stages, rather than transmitted to the device fabrication stage. It is therefore possible to incorporate the transfer device into an appropriate production device for these components, just before it is used in the component manufacturing < device. The device that executes the basic method generates data based on the numerical analysis of the PL response, for example, as described, the average PL signal throughout the entire area or a collection of local area data. Compare this information with predetermined acceptable specifications.

86767.DOC -18-200411167 $ Yes, in order to implement the above-mentioned improved alternative method, the device preferably needs to additionally include parsing the collected PL data into a spatially-resolved pL map that runs through the semi-conductor structure region. Component 'and additionally include, if necessary, two resolutions <data conversion—PL image component, and / or storage of the mapping / image' and, in particular, continuous image / data storage of continuous mapping / images for future comparison, and / or The mapping / image is transmitted to an appropriate remote data processing I component, and / or an image display component such as a visual display screen that displays an image and / or related data to a user. In another aspect of the invention, 'a computer program and / or a suitable stylized computer is provided to perform some or all of the steps of the method described herein, and in particular to perform data processing steps on the collected PL data, for example In other words, the average PL of the entire wafer area is measured, and / or analysis is performed from the collected data, and / or the average value is compared with a predetermined acceptable specification range. [Embodiment] The device shown in the figure mainly includes a pL imaging microscope, and the center: right-hand side, including a group of lasers (3_8); towards the bottom, including the same: stage, such as -X · Υ 台 or R The left-hand side includes a microprocessor (40) and a display screen (39), and the center of the figure shows various optical elements for detecting light passing through the system. In the embodiment shown in FIG. 1, six laser beams are provided to detect different depths in the sample. However, it is within the scope of the present invention to use only one laser, or to use a larger number of lasers exactly. In any case, at least -beams of such lasers are 咼 -intensity lasers, and ideally have a thickness of 0.1 mm to 0.5

86767.DOC -19 · 200411167 micron spot size and power density between 104 and 109 watts / cm². A laser selector (16) that is lightly connected to the group of lasers is provided to select one or more lasers for use, and the frequency and wavelength of these lasers are also selected. Use conventional optical devices, such as optical fibers (9) to direct light towards the collimator (10) and laser beam expander (11). Place all toe plates (丨 2) between the laser beam expander (11) and the beam splitter (31). The beam splitter (3 ^ directs a part of the light from the aforementioned laser toward the sample (2) by the objective lens (34). An autofocus controller (30) is provided and is coupled to a piezoelectrically driven focusing stage (33). The microscope is equipped with a conventional turntable (36), which has at least one high numerical aperture objective lens for microscopic inspection and a low numerical aperture objective lens (34, 35) for macroscopic inspection. In addition, An optical displacement measurement system (38) is also coupled to the turntable (36). Cable laying is provided to connect the autofocus controller (30) to the microprocessor (40) 'and also separate a microscope objective lens The degree device (32) is connected to the microprocessor (40). There is a filter wheel (13) with a laser notch filter downstream of the beam splitter (31), and a side swinging downstream of the filter wheel (π). The folding mirror (14) 'will be described in the following. Its function is to line up with the mirror (14). A filter wheel (27) for long selection, and one and one appropriate after the filter wheel (27). Zoom lens connected to CCD 2-D array detector (29). Optics in front of cold mirror (17) There is an infinite system compensation lens (37) in the path, which reflects light to another filter wheel (23) and a focusing lens (24) for wavelength selection. The focusing lens is in a UV and visible light detector ( 25)

86767.DOC -20- 200411167. Detected as (25) Li Yu connected to the lock-in amplifier (26). It is used to obtain a reflection image of one of these surfaces. On the rear surface of the cold mirror (17), there is another filter wheel (18) for wavelength selection, and at the end of the filter wheel (18), there is a focusing lens (22) and another for pinhole selection. The aperture wheel (19), the aperture wheel (丨 9) is at the front of the detector (21) for detecting light emission. UV and visible area detection (25) and infrared detector (21) are coupled to the lock-in amplifier (26). The operation of the system is explained below. A range of wavelengths is provided by several lasers (3-8) to detect different planes in the sample. The laser can be modulated by the frequency generator (16) so that the signal emitted from the sample (2) can be separated from the background radiation by the detector, and the detector and the detector can be locked by the lock-in amplifier (26). Laser modulation frequency is synchronized. In another embodiment, the range of wavelengths can be generated by using a tunable laser and / or an optical parameter oscillator. Each beam is connected to a multi-branch optical fiber (9) and aligned with it so that any or all such lasers can illuminate the sample (2). The common ends of the multi-branched optical fibers terminate in an optical system (10) that collimates the light that appears. The optical system is aligned with a beam expander (11) which matches the diameter of the laser beam to the required diameter of the microscope objective lens (34, 35) above the sample (2). The expanded beam then passes through an apodization plate (12) that distributes optical energy evenly over the beam area. The extended and apodized beam is reflected by a beam splitter (31), and the beam is passed to microscope objectives (34 and 35). The beam is focused on the sample by a microscope objective (34 or 35) 86767.DOC -21-200411167. In the micro mode, the objective is selected to focus the salt beam to a diffraction-limited spot size. The turntable (36), which is operated by an indexing mechanism, allows the objective lens to be transformed into a macro mode, in which a wider area of the sample can be projected. In another embodiment, the toe plate (12) can be removed, so that the spot size of the micro mode can be reduced to allow a higher injection volume. An optical displacement sensor (38) measures the distance of the sample and maintains the correct spacing generated by the piezoelectrically actuated focusing stage (33) through a feedback loop through an anti-focus controller (30). The photoluminescence signal from the sample is collected by the microscope objective (34) (which is in the micro mode), and transmitted back through the notch filter in the beam splitter (31) and the filter wheel (13). The filter wheel (13) Contains a notch filter that matches the laser wavelength range. The notch filter removes any reflected laser light and passes only the photoluminescence signal. Turn the folding lens (14) out of the beam to allow the signal to pass to the barrel lens (37) and to the cold mirror (17) 'where the barrel lens (37) can be incorporated to compensate for any infinite microscope that can be used Objective lens. The cold mirror (丨 7) reflects these wavelengths below the selected cutoff point (about 700 nm) to a focusing lens (24) that focuses the signal into the detector (25). One of the filters in front of the detector focusing lens (24), and the optical wheel (23) contains filters to separate the selected wavelength band. The photoluminescence signal portion in the wavelength range above the cut-off point passes through the cold mirror (17) and is similarly focused into the detector (2i) by the lens (22). The signal also passes through a filter wheel (18) containing filters to separate the selected wavelength band. An aperture wheel (19) placed before the detector (21) contains a series of 86767.DOC -22- 200411167 different straight ^ ·? / Ambiguous pinholes. The hole can be moved axially by a piezoelectric actuator (20) so that the pinholes can be placed so that they are confocal with the desired image plane. In this way, planes at different depths in the sample stack can be imaged to provide accurate depth information. The electric signal from the detection gain (21, 25) is supplied to the lock-in amplifier (26), and the lock-in amplifier (26) makes the electric signal and the laser (3_8) by a reference signal from a frequency generator (15) ) 'S modulation frequency is synchronized. This electrical signal is then supplied to a central processing unit (40) for analysis. The PL # image was acquired by raster scanning the sample stage 乂. Alternatively, optical scanning using a galvanometer mirror can also be used. In another operating micro mode, the folding mirror (14) is turned into the light beam of the photoluminescence signal. The steering signal passes through a filter wheel (27) and enters the zoom lens (28), wherein the filter wheel (27) includes a filter to separate the selected wavelength band. The zoom lens allows the illuminated spot on the sample (2) to be imaged on a CCD two-dimensional array (29) with different magnifications. This allows imaging of the illuminated area of the sample (2) at different resolutions. The electric vanadium from the CCD array was supplied to the central processing unit (40) for analysis. The processing of the data is shown diagrammatically in Figure 2. The sample (101) is transmitted to a sampling base by the control arm (102) to be tested by the device in the figure to generate a PL signal. The signal is collected by the collection device (shown as a device 105 in the form of a simplified diagram) in the figure. The figures show further processing of information. In a first processing path, according to the main point of the present invention, the PL mapping data is transmitted to the processor, which processes the # data to determine the average PL intensity across the entire area of the sample (101). 86767.DOC -23- 200411167 The obtained average value is passed to the comparator _, which correlates the average PL strong production data with the data storage specification range _ in the data record) and based on the comparison, the product The dragon judgment is transmitted to the control unit ⑴ ^. In this embodiment, the control unit ⑴Q) (Samples (1G1 then called on the job, the manipulator arm) directly transmitted manipulator arm to - element manufacturing process line or transmitted to - exclusion line in order to take appropriate positive measures alternative mode of operation, the control unit ⑴〇) may (for example) to - give an indication of the display member to the operator, the operator can then by separated control member (such as Xin) in order to make an acceptable / negative selection operating arm ⑽), to the test sample is transferred to the correction processing and the like. The dotted line shows a second processing path, which reflects an alternative second aspect of the present invention. Alternatively in this aspect of the same through the sample with ⑽) of PL information corresponding to the transmitted intensity mapping the surface of the second processing _ Where a single port (111), the processing unit ⑴υ may parse through the information is _ digitized samples of the surface of the space (101) parsing the intensity mapping. Pass the obtained mapping: data memory (112) and visual display (113). The resolved data can be used to identify the location of the defect. In this way, the basic device can be used to quickly screen inking circles. The location of the contamination can be mapped from the wafer, and then the wafer can be further analyzed using TXRF technology to identify impurities. It is not shown in Figures 3 and 4 that the technology can be used to monitor the amount of capital introduced into the wafer. First, be selected from different wafers from different wafer manufacturers. The measurement results are shown in Figure 3. There are obvious differences in the PL signals obtained from various suppliers', which cannot mean a change in the density of the surface defects by the amount of surface contamination. Batch of wafers from various suppliers were into - further measurements. Figure 4 shows

86767.DOC -24- 200411167 A typical example. Wafers from the same supplier have the same average value, and this characteristic was found to be general. So can that average? B is used as a measure for the quality of the introduced crystal circle. To implement the basic method of the present invention, the -PL mapping is collected and processed, and an average PL value is calculated, and then the average value is compared with a predetermined value. This specific range is used to determine the quality of the wafer and, as a result, an acceptance / rejection process control program is generated. Figure 5 shows the program graphically. By setting the specific range, the range can then be associated with any color or grayscale pattern, and a corresponding image can be prepared. Figure 9 shows an example. In this example, the black areas in the wafer map are shown outside the specified range. This simple code can be used to demonstrate miniaturization in wafer quality. &lt; After observing wafer quality using the average PL signal level, further measurement results can be recorded with higher resolution PL imaging technology and / or other techniques for wafers that do not meet the specifications. This will allow us to determine the type of defects present, while detecting in more detail the spatial changes that can give a clearer indication of the source of the contamination, such as 'poor surface grinding or incomplete cleaning'. To identify the source of contamination on the front side, the back side of the wafer can be recorded at the same time. By comparing these wafer maps, it is clear whether contamination originates from the back of the wafer. Then I can take further steps to prevent cross-contamination of other metrology II process instruments. Therefore, according to the present invention, a photoluminescence tool can be used as a rapid process control tool to determine wafer quality. Obtain wafer mapping and numerically analyze the PL response of 86767.DOC -25- 200411167 to provide a quality metric 'where photoluminescence responds to predetermined parameters known to the virtual jade people that are related to semiconductor structures with good quality: indirect Deviations are used as the basis for quality control decisions. In the given base example, it may be simply a comparison of the average response over the entire area. However, in general, contamination can be very local, and the average PL signal (the average value over all measured pixels in the wafer map) may not be a reliable indicator of the contamination. If you use —20 grid subdivision wafer mapping ’, the average PL analysis can be used to detect very specific signals. After recording-wafer mapping, a virtual grid can be applied, and it is mapped onto the wafer using the appropriate model. You can use this virtual grid to perform analysis. At the same time, local area analysis also allows better positioning of problem locations in the structure. For example, a failed grid element can be indicated; a micro-scan can be initiated at the same location as the grid element to allow more detailed inspection of the area of interest; and a failed form of wafer mapping analysis can be output in an appropriate form Record of components. The local grid method is not limited to numerical analysis based on average values. Any appropriate pre-specified parameters (including average intensity, pL minimum, maximum, standard deviation, and baseline) can be used to determine the contaminated area. Since the variation of the signal across the wafer is not uniform, the p L signal baseline method can be a more useful parameter. This technique will be explained below. Fig. 7a shows a typical inscribed circle map, and Fig. 7b shows a related intensity histogram. Detect contamination by deviation from baseline in wafer mapping, and can be set

86767.DOC -26- 200411167. E η 1- Cloth and left foot, can be corrected by contamination of the wafer map p] L average. 2. The value should represent the signal level of an uncontaminated wafer. The :: peak in Figure 8 represents the true tie value of an uncontaminated wafer. Correcting the baseline function and having peaks will allow users to accurately track pollution and have higher sensitivity—a suitable algorithm includes the following steps: The bounding peak is the maximum value in the histogram and is used for the baseline. 2. Search for peak data. ; ,,: After calculating the maximum value of soil 70% (which is defined by the user), then redefine the acupressure maximum value to the center position of these points. 4. Then calculate the exact value of the maximum peak value and then define the PL level. 5. Also allow 4 users to enter typical baseline values from uncontaminated wafers. It will be helpful if there are two peaks of equal intensity. The baseline of the wafer is the PL value corresponding to the maximum number of points. Baseline deviation is defined by the following relationship: Baseline deviation outside B value · Baseline PL value is the AVG PL of each element of the grid. Baseline deviation must be measured for each component. Soil 7 [Schematic description] The present invention has been described above by way of example with reference to the attached drawings 丨 to 8 only. Figure 1 is a diagrammatic illustration of a suitable device for obtaining PL data; Figure 2 is a diagram showing how Schematic diagram of processing data; Figure 3 shows the hole signals of wafers supplied in different batches recorded according to the present invention; 86767.DOC -27- 2UU41110 / Figure 4 shows the root number; Fig. 5 shows the correlation between the PL data and the one between the basic quality control acceptance / exclusion judgments of the PL message; Fig. 6 shows—Yuanyuan,, Yueyue &lt; Spatially parsed PL images; Back to 8 shows a possibility according to the present invention Numerical analysis techniques. [Schematic representation of symbols] 2 3-J 9 10 11 12 13 ， U ， 23 ， 27 14 15 16 17 19 20 21 22 ， 24 25 sample stage sample laser optical fiber collimator laser beam expander apodization Plate filter wheel folding mirror frequency generator laser selector cold mirror aperture wheel piezoelectric actuator infrared detector focusing lens UV and visible area detector

86767.DOC -28- 200411167 26 Lock-in amplifier 28 Zoom lens 29 CCD two-dimensional array 30 Automatic focusing controller 31 Beam splitter 32 Objective indexing device 33 Piezo driven focusing stage 34, 35 Microscope objective 36 Turntable 37 Lens tube lens 38 Optical displacement measurement system 39 Display screen 40 Microprocessor 101 Sample 102 Manipulator arm 103 Sampling base 105 Collection device 107 Processor 108 Comparator 109 Data memory 110 Control unit 111 Second processing unit 112 Data memory 113 Visual display 86767.DOC -29-

Claims (1)

Scope of patent application: A method for quality control of a semiconductor structure such as Shi Xi before component manufacturing on a 10,000-semiconductor to structure, which includes the following steps: obtaining a semiconductor before manufacturing the component; "Exposing the surface of the semiconductor structure to an N-intensity beam from a suitable light source, and collecting the photoluminescence (PL) generated by the beam stimulating the semiconductor structure; &amp; analysis, and use this analysis as the basis for a quality rating of the suitability of the semiconductor for device manufacturing. '2. The method as claimed in claim 4 wherein the quality grading step includes: measuring the average photoluminescence intensity emitted through the structural region or a subregion thereof; The specification range is accepted for comparison; based on the comparison, a quality classification is performed on the semiconductor structure. 3. If the method of the U.S. Patent Application No. U2, the quality grading step includes excluding or selecting-showing outside-the predetermined acceptable specification-photoluminescent response semiconductor surface to take corrective measures. 4. If _ please the method of the scope of the patent, the method is applied to the semiconductor structure before component manufacturing. For the introduction of semi-conductors such as broken 86767.DOC m duplex-quality control measures' -The element has been manufactured after being manufactured into potassium, and the method includes the following steps: According to the method described above, the phase-testing-series of these introduction junctions will be within the predetermined acceptable specifications of the photoluminescence, The photoluminescence response structure is passed to the element manufacturing stage, and the photoluminescence response structure that is out of the acceptable specification range of the luminescent emission is excluded from the element manufacturing stage. For example, the method of claim 4 in which the excluded structure is then passed to take corrective measures such as by cleaning, and then retesting and repeating the acceptance / exclusion steps as in claim 3 of the patent scope. The method of claiming patent &amp; ϋ item 1 or 2 is to control the beam's beam power, power rate and / or spot size to collect near surface PL information from the upper part of the semiconductor structure. For example, the method of claim 6 in the patent application range, wherein the light beam is controlled to collect near-surface p] L information from the upper part of the semiconductor structure at a micron. The method is called the patent scope item 1 or 2, in which the pL response is obtained at about room temperature. ~ Patent method 1 or 2, where the light source is a high-intensity laser 0 As in the method of patent claim 9, the laser has a spot size of 0.1 to 20 microns, which is ideal It has a small detection capacity of 2 to 5 microns and a peak or average power bifurcation between 104 and 109 watts per square centimeter. For example, the method of claim 10 of the patent scope, wherein a pulsed laser excitation source is used and the luminescence data is measured, and / or these luminescence images are collected as a -2- 200411167 time function. 12. The application method 1 or 2 of the scope of the patent, which additionally comprises using PL signal such as to generate a collected signal through pL of the test surface of a semiconductor one spatially resolved map, and in particular the generation of such signals The steps of a spatially resolved image. 13. The method according to item 12 of the scope of patent application, which further includes storing the spatially resolved PL map on an appropriate data storage component, and / or transmitting the digitized data obtained from the spatially resolved map to the prior to the step of processing supplied. , 1 &quot; +. ^, The method of patent application item No. 13 further includes the step of displaying any PL image on an appropriate display member. a The method according to item 13 or 14 of the scope of patent application, which further includes the following step: using the spatial analysis map to identify the approximate location of the cold dye. ^ using a specific analysis technique such as Position, further analyze the semiconductor structure to identify the impurity. 16. A method of characterizing and / or characterizing a material dye in a state such as = a conductor structure in a state of clearing, which includes performing on top of one of the structures as described in the patent scope One method is only in the scope of patent application for those structures that have been excluded because they show an acceptable specification range in the pre-, ',, and ζ. &Quot; Items 2 to 15 are performed as .. ,, a ^ @ ^ f steps outside the head to generate a spatially resolved asset section on the excluded structure. * 17. · Before the manufacture of components on semiconductor structures, the quality control device for the conductor structure ..., "Half-eight daggers ... a high-intensity light source 86767.DOC 200411167; the high intensity from this light source The beam is focused on a component on a surface of the semiconductor structure under test; a collection member that collects photoluminescence data generated by stimulating the semiconductor structure with the light beam and penetrates the surface of the semiconductor structure under test; an analysis member, which Processing and numerical analysis of the collected &lt; data comparator &quot; which compares the results of these analyses with predetermined acceptable specifications; and-may transfer the structure to a specific down-processing stage of the transmission component, where whether the photo luminescent signal within the predetermined range of acceptable specifications. Wai is determined whether or not the transmission 18. the device of claim 17 of the patent range, wherein the beam of the beam power and / or wavelength and / or flare controlled size such that the apparatus is adapted to generate and to collect information from the upper pL near surface of the semiconductor structure of 12 microns. 19. the scope of patent The device according to item 17, wherein the beam power and / or wavelength and / or spot size of the light beam is controlled so that the device can collect near surface information from the upper surface of the semiconductor structure and the micron at 1 μm. 20 as the scope of patent 17, 18 or 19 wherein apparatus according to any one of the high-intensity light source is a laser. 21. the apparatus of Paragraph 2〇 patentable scope of application, wherein the laser has a spot size of square · 1 to 20 microns, more desirably from 2 to 5 microns and a peak or average power of the small probe capacitance between 10-1 watt / cm ^. 22. the patent application of 17, 18 or 19 range The device of any one of the preceding clauses, wherein the transmission member is adapted to transmit a structure that displays a photoluminescence response within the predetermined acceptable specifications of photoluminescence to a component manufacturing stage, and transmits a display A photoluminescence response structure that is outside the predetermined acceptable range of photoluminescence is transmitted to, for example, an obsolete 86767.DOC -4-23 billion installation or correction process stage, rather than to the component manufacturing stage. Xi Shen μ patent scope The device of any one of items 17, 18, or 19 further includes parsing the PL data collected by the child into a spatially-resolved PL and mapping member that runs through the area of the semiconductor structure. A device of 23 items, which additionally includes a component that converts the Xuanxuan data into a PL image, and / or an image / asset storage component that stores the mapping / image, and especially stores continuous mapping / image for future comparison, And / or transmitting the mapping / image to an appropriate remote data storage device 'and / or displaying an image and / or related data to the user, an image display component such as a visual display screen . 86767.DOC