JP4841489B2 - GETTER EVALUATION SYSTEM, ITS EVALUATION METHOD, ITS EVALUATION PROGRAM, AND GETTER EVALUATION DEVICE - Google Patents

Description

  The present invention relates to a getter evaluation system, an evaluation method thereof, an evaluation program thereof, and a getter evaluation apparatus.

  The technical field to which MEMS (Micro Electro Mechanical Systems) devices using silicon are applied is steadily expanding, and in recent years, the technology has been applied not only to micro turbines and sensors but also to information communication field and medical field. Yes. One of the main elemental technologies that support this MEMS technology is a technology related to getters, and especially in the field of sensors and the like that are further miniaturized, development of various technologies related to the getters is indispensable.

  Here, the development of the getter is made integrally with the evaluation of the gas absorption performance of the getter, but at present, the evaluation using the original means by each getter manufacturer, or the standardized means, The absorption performance of the getter is shown. However, even if standardized means are used, it is merely evaluating the absorption performance immediately after formation of the getter. Therefore, it can be said that it is almost impossible for the user of the getter to evaluate the accurate ability of the final product of the getter incorporated into various devices through several heat treatment steps and gas exposure steps.

This problem is not just limited to the MEMS field. An accurate evaluation of the gas adsorption capacity of the getter is also required in order to obtain an accurate evaluation of the lifetime of a cathode ray tube such as a cathode ray tube (see, for example, Patent Document 1).
JP 2000-76999 A

  As described above, the getter is an important and indispensable technical element for maintaining the performance of the final product in various technical fields. Therefore, there is a strong demand for a technique for accurately evaluating the performance of getters incorporated in various devices through actual manufacturing processes.

  The present invention solves such technical problems and greatly contributes to the advancement of technology for evaluating the performance of getters incorporated in various actual final products. First, the inventor generally uses a getter as a part of a device, and generally the initial getter or purchase getter has multiple heat treatment steps and gas exposure steps before becoming a final product. Focused on what must be done. In other words, it is extremely rare that the performance of the original getter is maintained as it is, and the final product is rarely obtained. This will cause a decrease in gas adsorption capacity due to exposure. However, these processes are very different even if they take a single MEMS field. Therefore, how accurately the initial getter performance is evaluated reflects how much it is reflected in the final product. It is virtually impossible to predict.

  Therefore, if the inventor can include a device for evaluating the performance of the getter in the substrate used for actual production or in a part of the production lot, the device goes through the same process as the actual product. Therefore, it was thought that the gas absorption capacity of the getter in the final product could be accurately grasped. As means for realizing this, the inventor pays attention to the Q value of the vibrating body as one of the parameters that accurately reflects the pressure in the sealed space, and keeps in mind that the performance evaluation of the getter is reflected in the Q value. We conducted intensive research. As a result, the inventor found an apparatus including a vibrating body and a getter that can form a part of a production lot in a substrate used for actual production, and a getter evaluation means using the apparatus. completed.

  One getter evaluation apparatus of the present invention is connected to and absorbed by one sealed space, a getter disposed in the sealed space, and a sealed channel provided with a partition wall. One or more other sealed spaces in which possible gas is sealed, and a vibrator formed in each sealed space in which the getter is disposed or in which a gas that can be absorbed by the getter is sealed. It has. In addition, this evaluation apparatus allows the gas to flow into the sealed space in which the getter is disposed by removing at least a part of the partition wall using a laser.

  With this evaluation device, the performance of the getter incorporated in the final product can be evaluated. Specifically, the plurality of sealed spaces before and after penetrating a partition wall that prevents gas movement between the sealed space in which the getter is disposed and the sealed space in which the gas that can be absorbed by the getter is sealed. Based on the fluctuation of the Q value of the vibrating body, the remaining adsorption performance that the getter has at the stage of the final product can be known.

One getter evaluation system according to the present invention is connected to and can be absorbed by a sealed space, a getter disposed in the sealed space, and a sealed channel with a partition wall. One or a plurality of other sealed spaces in which various gases are sealed, and a vibrator formed in each sealed space in which the above-described getters are disposed or in which a gas that can be absorbed by the getter is sealed. A stage on which the getter evaluation device is provided, a laser oscillator having an output for removing at least a part of the partition wall, and a control for controlling the irradiation condition of the laser irradiated by the laser oscillator parts and, Q value of the first vibrator whose getter formed arranged sealed space (hereinafter referred to as Q ₁ value), and at least a gas are sealed Formed vibrator in one sealed space by Q value (hereinafter, collectively referred to as a second vibrator to) (hereinafter referred to as Q ₂ values collectively), and at least a portion of the removal of the partition wall the first vibrator or Q value of the second vibrator in the aforementioned post through a measuring device for measuring a (hereinafter, collectively referred to as Q ₃ value is), the measurement control unit for controlling the instrument, the above Q ₁ value, and includes a storage unit for storing Q ₂ values and Q ₃ value, Q ₁ value described above, Q ₂ value, and a calculation device for calculating the gas absorption by getter from Q ₃ value.

  According to this evaluation system, the performance of the getter incorporated in the final product can be evaluated. Specifically, the plurality of sealed spaces before and after penetrating a partition wall that prevents gas movement between the sealed space in which the getter is disposed and the sealed space in which the gas that can be absorbed by the getter is sealed. The fluctuation of the Q value of the vibrating body is measured and stored. Based on the measurement result, the residual adsorption performance that the getter has in the final product stage can be calculated. In addition, although the above-mentioned measuring device does not need to measure both the Q values of the first vibrating body and the second vibrating body after penetration by removing at least a part of the partition wall, both of them should be measured. Is a preferred embodiment because it contributes to improvement in evaluation accuracy.

In addition, the getter evaluation method of the present invention is connected to the sealed space through a flow path including a sealed space, a getter disposed in the sealed space, and a partition wall, and can be absorbed by the getter. One or a plurality of other sealed spaces in which various gases are sealed, and a vibrator formed in each sealed space in which the above-described getters are disposed or in which a gas that can be absorbed by the getter is sealed. equipped with the evaluation device of the getter, Q value of the first vibrator whose getter is formed on the arranged closed space (hereinafter referred to as Q ₁ value) and at least one closed space in which the gas is sealed formed vibrator within (collectively, the second vibrator) of the Q value and the step of measuring the (hereinafter referred to as Q ₂ values collectively) above for Q ₁ value and Q ₂ value A first storage step for storing After the first storage step, a laser removal step of removing at least a part of the partition wall with a laser and penetrating the laser, and after the laser removal step, the Q value of the first vibrator or the second vibrator (hereinafter referred to as Q ₃ value are collectively) a step of measuring a second storage step of storing the Q ₃ value, Q ₁ value described above, Q ₂ values, and the gas absorption by getter from Q ₃ value A step of calculating the quantity.

  According to this evaluation method, the performance of the getter incorporated in the final product can be evaluated. Specifically, the plurality of sealed spaces before and after penetrating a partition wall that prevents gas movement between the sealed space in which the getter is disposed and the sealed space in which the gas that can be absorbed by the getter is sealed. The fluctuation of the Q value of the vibrating body is measured and stored. Based on the measurement result, the residual adsorption performance that the getter has in the final product stage can be calculated. In the measurement step described above, it is not necessary to measure both the Q values of the first vibrating body and the second vibrating body after penetrating by removing at least a part of the partition wall, but both are measured temporarily. Since this contributes to improvement in evaluation accuracy, it is a preferable embodiment.

Further, the getter evaluation program of the present invention is connected to the sealed space through a flow path having a sealed space, a getter disposed in the sealed space, and a partition wall, and can be absorbed by the getter. One or a plurality of other sealed spaces in which various gases are sealed, and a vibrator formed in each sealed space in which the above-described getters are disposed or in which a gas that can be absorbed by the getter is sealed. the evaluation device of the getter with its first vibrator of Q values Potter material is formed on the arranged closed space (hereinafter referred to as Q ₁ value), and at least one of the gas is sealed formed vibrator in a closed space Q value (hereinafter, collectively referred to as a second vibrator to) the step of measuring (hereinafter, collectively referred to as Q ₂ values and) above for Q ₁ value and Q first storing _binary A storage step, a laser removal step for removing at least a part of the partition wall with a laser after the first storage step, and a first vibration body or a second vibration after the laser removal step. A step of measuring a body Q value (hereinafter collectively referred to as Q ₃ value), a second storage step of storing the Q ₃ value, and the above-mentioned Q ₁ value, Q ₂ value, and Q ₃ value A step of calculating the amount of gas absorbed by the getter is included.

  According to this evaluation program, the performance of the getter incorporated in the final product can be evaluated. Specifically, the plurality of sealed spaces before and after penetrating a partition wall that prevents gas movement between the sealed space in which the getter is disposed and the sealed space in which the gas that can be absorbed by the getter is sealed. The fluctuation of the Q value of the vibrating body is measured and stored. Based on the measurement result, the residual adsorption performance that the getter has in the final product stage can be calculated. In the measurement step described above, it is not necessary to measure both the Q values of the first vibrating body and the second vibrating body after penetrating by removing at least a part of the partition wall, but both are measured temporarily. Since this contributes to improvement in evaluation accuracy, it is a preferable embodiment.

  By the way, in any of the above-described inventions, if the number of sealed spaces in which the above-described gas is sealed is two or more, the amount of gas to be absorbed by the getter increases so that the gas absorption of the getter increases. The structure is suitable for evaluating the upper limit of capability. In any of the above-described inventions, it is preferable that the above-described vibrating body constitutes a part of the final product in the sealed space provided with the getter, but the invention is not limited thereto. For example, a vibrating body may be formed on a final product that does not normally require such a vibrating body for performance evaluation of the getter.

  The “measuring instrument” in the getter evaluation system of the present invention includes not only a single measuring instrument such as a network analyzer, but also a plurality of instruments that combine a signal generator capable of high-frequency oscillation and a frequency response measuring instrument. Including meaning.

  According to the apparatus for evaluating a getter of the present invention, the performance of a getter incorporated in a final product can be evaluated. Specifically, the plurality of sealed spaces before and after penetrating a partition wall that prevents gas movement between the sealed space in which the getter is disposed and the sealed space in which the gas that can be absorbed by the getter is sealed. Based on the fluctuation of the Q value of the vibrating body, the remaining adsorption performance that the getter has at the stage of the final product can be known. In addition, according to the getter evaluation system, the getter evaluation method, or the getter evaluation program of the present invention, the performance of the getter incorporated in the final product can be evaluated.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this description, common parts are denoted by common reference symbols throughout the drawings unless otherwise specified. In the drawings, the elements of the present embodiment are not necessarily shown to scale.

<First Embodiment>
FIG. 1 is a plan view of a getter evaluation apparatus 100 according to the present embodiment. FIG. 2 is a cross-sectional view taken along line AA of the getter evaluation apparatus 100 shown in FIG. 2 is a detailed view of an M portion of the getter evaluation apparatus 100 shown in FIG.

  As shown in FIG. 2, in the getter evaluation apparatus (hereinafter, also simply referred to as “evaluation apparatus”) 100 according to the present embodiment, one vibrating body 12 a and 12 b is provided in each of the two sealed spaces 11 a and 11 b. The sealed spaces 11a and 11b are connected to each other through a flow path 14 having one partition wall 13. Here, the sealed spaces 11a and 11b are formed by being sandwiched between a lower glass substrate 16a in which relatively deep holes 15a and 15a are formed and an upper glass substrate 16b in which relatively shallow holes 15b and 15b are formed. The A probe through-hole 17 for measuring the Q value of the vibrating bodies 12a and 12b is formed in the upper glass substrate 16b. On the other hand, a titanium film 18 as a getter is formed on the bottom surface of one hole 15a of the lower glass substrate 16a. Furthermore, hydrogen and / or nitrogen that can be absorbed by the getter is sealed in a sealed space different from the sealed space 11a where the getter film is formed at a pressure of 133 Pa to 1330 Pa.

  Here, in the present embodiment, the vibrating bodies 12a and 12b, the partition wall 13, and the flow path 14 are all formed of silicon. A known silicon anisotropic etching technique is used to form the vibrating bodies 12a and 12b. Specifically, a mask is formed on a silicon layer or silicon substrate having a thickness of about 50 μm to 200 μm so as to have the shape shown in FIG. 1 by a known photolithography method. Thereafter, this substrate is etched by, for example, a gas switching process disclosed in Japanese Patent Application Laid-Open No. 2007-35929. Subsequently, the silicon substrate formed into a vibrating body by etching is subjected to anodic bonding using a known condition (for example, the condition described in Japanese Patent Laid-Open No. 2005-16965), and the two glass substrates 16a and 16b described above. It is sandwiched and joined. In this manufacturing process, the getter evaluation apparatus 100 experiences a heat treatment step of about 400 ° C. at least once.

  In the present embodiment, the vibrating bodies 12a and 12b described above are the same silicon as the angular velocity sensor (for example, see FIG. 4 of Japanese Patent Laid-Open No. 2006-38645) which is a MEMS device having the same shape except for a part thereof. It is formed on a substrate. Therefore, since the getter evaluation apparatus 100 is formed through the same process as the manufacturing process of the angular velocity sensor, it is possible to evaluate the performance of the titanium film 18 as the getter in the final product.

  Further, the titanium film 18 serving as a getter is formed on at least the bottom surface of one hole 15a by a known sputtering method or vacuum deposition method with a part of the lower glass substrate 16a covered with a mask.

  By the way, in this embodiment, since the vibrating bodies 12a and 12b are formed integrally with the above-described silicon substrate with the angular velocity sensor, it is not necessary to separately manufacture only the vibrating bodies 12a and 12b. It is reduced. Furthermore, for example, it is a preferable aspect to form the vibrating body for the above-described getter evaluation apparatus 100 on a part of each silicon substrate of the production lot. Thereby, since the quality of the final product can be confirmed for each production substrate, there is an advantage that the inspection accuracy of the final product is improved. Needless to say, it is also preferable from the same point of view to form the vibrating body for the getter evaluation apparatus 100 described above on every predetermined number or random number of silicon substrates. Moreover, in this embodiment, although the angular velocity sensor was made into an example of a MEMS device, it is not limited to this. For example, an acceleration sensor, a pressure sensor, or an optical MEMS is given as another example of a device that is formed integrally with the getter evaluation apparatus of the present embodiment using a silicon substrate.

  Next, vibrators 12a and 12b as an example of the present embodiment will be described with reference to FIG. Typically, the vibrating body 12a is supported by the central portion 21 and is connected to the eight beam portions 22 and eight beam portions (beams) 22 that extend in the circumferential direction and are equally spaced by eight. An annular ring portion 23 is provided. A DC voltage can be applied from the DC power supply 26 to the central portion 21 of the vibrating body 12a. An AC voltage can be applied to the drive electrode 24 from an AC power supply 27. Further, on the outside of the ring portion 23, a driving electrode 24 for causing vibration to the vibrating body 12a and a detection electrode 25 for detecting the resonance frequency of the vibrating body 12a are provided.

  Next, the getter evaluation system in this embodiment will be described. FIG. 4 is a configuration diagram of the getter evaluation system 200 in the present embodiment. The getter evaluation system 200 includes a stage 31 on which the getter evaluation device 100 to be evaluated is placed, and a probe 34 for measuring the Q values of the vibrators 12a and 12b of the evaluation device 100. A network analyzer 33, a laser control unit 35 that controls the laser irradiation conditions, a laser oscillator 36 that irradiates the partition wall 13 with lasers under the conditions specified by the laser control unit 35, and the network described above. A measurement control unit 37 for controlling the analyzer 33, a storage unit 38 for storing the measurement result by the network analyzer 33, and a calculation device (computer) 39 for calculating the gas adsorption amount of the getter from the measurement result are provided. Here, in the present embodiment, the measurement control unit 37 and the storage unit 38 are housed in a computer 39. The stage 31 is disposed on the table 32 so as to be movable along the XY axes, and can be moved to a desired position by a known movement control means. Further, a CCD camera for alignment and an autofocus function at the time of laser irradiation are appropriately added to the system using a known apparatus.

  By using this evaluation system 200, the gas absorption performance of the getter is evaluated according to the process flowchart shown in FIG.

  First, in step S11, the Q values of the vibrators 12a and 12b arranged in the getter evaluation apparatus 100 are measured.

Specifically, as shown in FIGS. 1 to 4, when attention is paid to a vibrating body (hereinafter referred to as a first vibrating body) 12a formed in a sealed space where getters are arranged, the Q value is as follows. Is measured. First, the stage 31 on which the getter evaluation device 100 is mounted moves, and the probe 34 contacts the drive electrode 24 and the detection electrode 25. Next, an AC voltage is applied from the network analyzer 33 to the drive electrode 24 in response to an instruction from the measurement control unit 37. This AC voltage causes the vibrating body 12a of the getter evaluation apparatus 100 to vibrate. Here, the measurement control unit 37 sequentially varies the frequency of the AC voltage via the network analyzer 33, whereby the amplification of the output signal with respect to the input signal of the vibrating body 12a is measured by the network analyzer 33, and the vibrating body 12a. Is detected (hereinafter also referred to as ω ₀ ). The change in the value of the vibration energy with respect to the change in the frequency of the AC voltage is sequentially stored in a memory provided in the network analyzer 33 or a storage unit 38 in the computer 39.

Similarly to the detection of the ω ₀ value, in the resonance waveform acquired by the network analyzer 33, the frequency ω ₁ that is a frequency lower than ω ₀ and half the vibration energy value that is the resonance peak, and the resonance waveform In the waveform, a frequency ω ₂ that is higher than ω ₀ and half the vibration energy value that is the resonance peak is detected and stored in the memory provided in the network analyzer 33 or in the storage unit 38. .

When the above-described ω ₀ , ω ₁ , and ω ₂ are detected, the Q value is calculated using the following mathematical formula.

The Q value (hereinafter referred to as _{Q 1)} is stored in the recording unit 38 (step S12).

Furthermore, since the vibrating body (hereinafter referred to as the second vibrating body) 12b is also formed in the sealed space 11b different from the sealed space 11a in which the first vibrating body 12a is disposed, similarly to the first vibrating body 12a, Q value of the second vibrator 12b (hereinafter referred to as _{Q 2)} is also measured and stored in the recording unit 38 (step S12).

For convenience, the Q value of the vibrator 12a of the initial closed space which a titanium film 18 was formed as Q _1, initially, hydrogen and / or Q value of the vibrator 12b in the closed space in which the nitrogen is sealed It is referred to as _{Q 2.} At this point, since the reduced pressure of the gas present in the sealed space 11a of the titanium film 18 is formed as compared with that in the other sealed space 11b, and has a Q _1> Q _2.

  Next, in step S13, a part of the partition wall 13 is removed by laser irradiation. Thereby, hydrogen and / or nitrogen sealed in the other sealed space 11b flows into the sealed space 11a in which the titanium film 18 is formed.

Specifically, as shown in FIGS. 1 to 4, first, the stage 31 on which the getter evaluation apparatus 100 is placed moves below the laser oscillator 36. Next, in response to an instruction from the laser control unit 35, a laser is emitted from the laser oscillator 36 toward the partition wall 13. In this embodiment, a YAG laser having a wavelength of 532 nm is used as the laser. The laser irradiation conditions are an energy density of 1.28 × 10 ⁶ J / m ² and a pulse number of 300 Hz. As a result of a part of the partition wall 13 being sublimated or melted and scattered by this laser irradiation, a part of the partition wall 13 penetrates. Then, hydrogen and / or nitrogen sealed in one sealed space 11b flows into the sealed space 11a in which the titanium film 18 is formed.

  Thereafter, in step S14, at least one Q value of the vibrators 12a and 12b arranged in the getter evaluation apparatus 100 is measured again.

Since the specific measurement method is the same as that in step S11, the description thereof is omitted. Thus, for example, the partition wall 13 is the Q value of the one vibrating body after penetration (hereinafter referred to as Q ₃₎ is measured.

Subsequently, in step S <b> 15, the Q value (Q ₃ ) of the vibrating body after the partition wall 13 penetrates is stored in the recording unit 38. In the present embodiment, the above-described single vibrating body is the vibrating body 12a formed in the sealed space 11a in which the titanium film 18 before the partition wall 13 passes is disposed. Since the difference in the influence on the Q value due to squeeze film damping differs depending on the vibrating body due to the dimensional error between the gaps for each vibrating body caused by anisotropic etching of silicon when forming the vibrating bodies 12a and 12b, It is preferable to measure the Q value of the vibrating body 12a. On the other hand, in order to further improve the evaluation accuracy, it is a further preferable aspect that the Q values of both the vibrating bodies 12a and 12b are measured after the partition wall 13 has penetrated.

Thereafter, in step S16, the gas absorption amount of the getter of the present embodiment is calculated from the Q ₁ value, Q ₂ value, Q ₃ value, and the volume of each sealed space 11a, 11b stored in the storage unit 38. Is done.

  Here, in this embodiment, the relationship between the pressure P and the Q value in the sealed space in which the vibrating body is formed in advance is experimentally examined, and the relational expression is stored in the recording unit 38. This is because the relationship between the Q value and the pressure P is determined by the shape and material of the vibrating body. Accordingly, by examining the change in the Q value when the pressure P is first changed for any one vibrating body, the Q values of the vibrating bodies of other substantially the same shape and material are based on the aforementioned relationship. Thus, it is measured as an approximate value. As a means for experimentally investigating the relationship between the pressure P and the Q value in the sealed space, for example, a gas such as argon is introduced into one vibrating body of the upper glass substrate and a getter evaluation apparatus in which no getter is formed. A method of measuring the Q value of the vibrating body while measuring the pressure fluctuation in the chamber by introducing gas and placing in a possible vacuum chamber can be mentioned.

Specifically, the gas absorption amount (A) is calculated by the following formula. For convenience, the volume of the closed space 11a that getter film before bulkhead penetration is formed as a V _1, the volume of the other sealed space 11b and V _2. Similarly, the pressure of the sealed space 11a of the front partition wall portion through the _{P 1,} the pressure of the other closed space 11b and _{P 2.}

  As described above, the amount of gas absorbed by the getter that has undergone the same manufacturing process as the final product, that is, the performance of the getter can be evaluated.

<Second Embodiment>
Also in this embodiment, the same getter evaluation apparatus 100 and getter evaluation system 200 as in the first embodiment are used.

  FIG. 6 is a flowchart relating to the gas absorption performance evaluation process of the getter in the present embodiment. In the present embodiment, steps S21 to S25 are the same as steps S11 to S15 of the first embodiment, and thus description of this portion is omitted.

Here, step S26 and subsequent steps will be described in detail. In step 26, the determination unit 40 provided in the computer 39 determines that the relationship between the Q ₁ value and the Q ₃ value stored in the storage unit 38 so far is 1 for the former and 0.95 or more for the latter. It is determined whether or not. Here, the value of 0.95 or more is taken into consideration of variations in measurement accuracy due to actual measurement equipment. Empirically, Q ₃ value if falls below this value, the gas absorption performance by initial getter by penetrating the partition wall 13 of the evaluation device 100 of the getter is considered to have been fully exhibited. Therefore, based on the above criteria, if the relationship between the Q ₁ value and the Q ₃ value is 1 for the former and less than 0.95 for the latter, it is additionally Thus, the laser absorption is not performed and the gas absorption amount shown in step 27 is calculated.

On the other hand, when the relationship between the Q ₁ value and the Q ₃ value is 1 for the former and 0.95 or more for the latter, particularly when the Q ₁ value and the Q ₃ value coincide, It can be seen that the gas absorption performance by the original getter remains even through the penetration. In this case, as shown in step 28, under the same conditions as in the first embodiment, a partition different from the partition 13 of the getter evaluation device 100 that penetrated first (hereinafter also referred to as “other partition” for convenience) 13 is irradiated with a laser. As a result, the titanium film 18 serving as a getter is exposed to the newly introduced gas, and the gas is additionally absorbed by the titanium film 18.

Thereafter, in step S29, at least one Q value of the vibrator arranged in the getter evaluation apparatus 100 is measured again. A specific description of the measurement method is the same as step S11 in the first embodiment, and will be omitted. Thus, other bulkhead 13 Q value of the vibration of one of the post through (hereinafter referred to as Q ₄₎ is measured.

Subsequently, in step S <b> 30, the Q value (Q ₄ ) of the vibrating body after the other partition wall 13 penetrates is stored in the recording unit 38. Also in the present embodiment, the above-described single vibrating body is the vibrating body 12a formed in the sealed space 11a in which the titanium film 18 before all the partition walls 13 and 13 are disposed is disposed. is there. The reason is as described above.

In step 31, the determination unit 40 provided within the computer 39, until then the relationship between Q ₁ value and Q ₄ values stored in the storage unit 38, the latter is 0.95 or more with respect to the former one It is determined whether or not. At this time, if, Q relationship between ₁ value and Q ₄ value, if the former were the latter is less than 0.95 relative to 1, further additionally, to date other than the partition walls to penetrate the partition wall 13 is not irradiated with laser, and the amount of gas absorption shown in step 32 is calculated.

On the other hand, when the relationship between the Q ₁ value and the Q ₄ value is 1 for the former and 0.95 or more for the latter, particularly when the Q ₁ value and the Q ₄ value coincide with each other, the other partition walls described above are used. It can be seen that the gas absorption performance by the original getter remains even through 13 penetration. In this case, the process returns to the above-described step 28, and additionally, the laser is irradiated to the partition walls 13 other than the partition walls that have been penetrated so far.

  Thereafter, according to the determination in step 31, the processes in and after step 28 are repeated. As a result, the gas absorption capacity of the getter can be evaluated with higher accuracy.

  By the way, the above-described series of processing (step S11 to step S16 or step S21 to step S32) can be executed using hardware, but can also be executed by software. Also in this embodiment, the laser control unit 35 and the measurement control unit 37 are all connected to the computer 39. Therefore, the computer 39 can monitor or comprehensively control the above-described processes by the getter evaluation program for executing the above-described processes.

In this case, the above-described evaluation program is stored in a known recording medium such as an optical disk or a magnetic disk inserted into a hard disk drive in the computer 39 or an optical disk or a magnetic disk drive provided in the computer 39. However, the storage location of this evaluation program is not limited to this. For example, part or all of the evaluation program may be stored in the laser control unit 35 and / or the measurement control unit 37 in each of the above-described embodiments. The evaluation program can also monitor or control each of the processes described above via a known technique such as a local area network or an Internet line.

  Further, in each of the above-described embodiments, the stage 31 is configured to move between the position measured by the network analyzer 33 and the position irradiated with the laser by the laser oscillator 36. However, the present invention is not limited to this. . For example, the network analyzer 33 and the laser oscillator 36 described above may be configured to move with respect to the fixed getter evaluation apparatus 100.

  In each of the above-described embodiments, the laser control unit 35 is arranged independently of the computer 39, but the present invention is not limited to this. That is, the laser control unit 35 may be arranged in the computer 39. Conversely, even if the storage unit 38 is arranged outside the computer 39, the same effect as the effect of the present invention is exhibited.

  Moreover, in each above-mentioned embodiment, although hydrogen and / or nitrogen are used as gas which a getter can absorb, it is not limited to this. For example, if the gas contains saturated hydrocarbon gas such as water vapor, oxygen, carbon dioxide, carbon monoxide, methane or ethane, or unsaturated hydrocarbon gas such as ethene or propene, the gas can be applied to the present invention. It is.

  Further, for example, as shown in FIGS. 8 and 9, the above-described connection with the sealed space 42 in which the gas that can be absorbed by the getter is not directly connected to the sealed space 41 in which the getter is disposed is connected. The getter evaluation apparatus 300 including the third sealed space 43 in which the gas is sealed is a preferable embodiment. If this configuration is adopted, a part of the partition wall 45 between the sealed space 42 and the sealed space 43 is not affected by the sealed space 41 in which the getter is disposed. It can be penetrated. As a result, the Q value of the vibrating body 47 or the vibrating body 48 can be measured in a state in which the amount of the gas is sufficiently large in advance. In addition, if the partition wall 44 is penetrated after the Q value of the vibrating body 46 is measured, the getter can be evaluated with a sufficient amount of gas that can be absorbed by the getter. This is not only possible to evaluate the performance of the getter incorporated in the final product, but it can be handled with only one structure pattern, independent of changes in gas absorption capacity caused by changes in getter type and formation method. This is also advantageous. If another sealed space similar to the third sealed space 43 is connected to the sealed space 42 via a flow path having a partition wall, the amount of gas can be further increased.

  Moreover, in each above-mentioned embodiment, although the number of the partition 13 formed in the flow path 14 was one, it is not limited to this. For example, in FIGS. 7A to 7D, the shape of the M portion in the first embodiment shown in FIG. 1 is changed by changing the etching mask, but as shown in FIGS. 7A and 7C, A plurality of partition walls 13 may be formed. Providing a plurality of partition walls 13 means that one partition wall cannot function due to failure of dimensional control when forming the partition wall 13 by the above-described anisotropic etching (in other words, a part of the partition wall 13 penetrates from the beginning. Is advantageous). From this viewpoint, the number of partition walls may be three or more for one flow path. Moreover, when the several flow path is formed, it is preferable from the said viewpoint that the several partition is formed in at least 1 of the flow path. In addition, the thickness of the partition wall is not particularly limited. However, while maintaining the function as the partition wall, a part of the partition wall is quickly removed by the laser, and there is a risk of adhesion on the getter due to scattering of silicon during the removal. The thickness is preferably 30 μm or more and 50 μm or less so that the property is excluded.

  Moreover, in each above-mentioned embodiment, although the shape in the top view of the flow path 14 was linear, it is not limited to this. For example, as shown in FIGS. 7B to 7D, it may have a labyrinth shape. Specifically, a meandering shape as shown in FIGS. 7B and 7C or a zigzag shape as shown in FIG. 7D may be used. Adopting such a labyrinth shape means that when the partition wall made of silicon is penetrated by a laser, the removed silicon flows into the sealed space where the getter is arranged and adheres to the surface of the getter. This is advantageous in that it can be prevented. From this point of view, it is preferable that at least a part of the entire flow path from the position where the partition wall is formed to the sealed space where the getter is disposed has a zigzag shape or a meandering shape. Two or more of the above-mentioned flow path shapes may be combined.

  Furthermore, in each of the above-described embodiments, the material constituting the partition walls is silicon, but is not limited thereto. For example, even if the partition wall is made of germanium or silicon germanium, it can be penetrated by laser irradiation. As described above, the modifications within the spirit and scope of the present invention are also included in the scope of the claims.

  The present invention is suitable for performance evaluation of getters, which are important and indispensable technical elements for maintaining performance of final products in various technical fields.

It is a top view of the apparatus for evaluation of a getter in one embodiment of the present invention. It is AA sectional drawing of the apparatus for evaluation of the getter shown in FIG. FIG. 2 is a detailed view of an M section of the getter evaluation apparatus shown in FIG. 1. It is a lineblock diagram of a getter evaluation system in one embodiment of the present invention. 3 is a flowchart of a process for evaluating a gas absorption performance of a getter in one embodiment of the present invention. It is a flowchart of the gas absorption performance evaluation process of the getter in other embodiment of this invention. It is a top view showing the flow path and partition in other embodiment of this invention. It is a top view showing the flow path and partition in other embodiment of this invention. It is a top view showing the flow path and partition in other embodiment of this invention. It is a top view showing the flow path and partition in other embodiment of this invention. It is a top view of the apparatus for evaluation of a getter in other embodiments of the present invention. It is BB sectional drawing of the apparatus for evaluation of the getter shown in FIG.

Explanation of symbols

11a, 11b, 41, 42, 43 Sealed space 12a, 12b, 46, 47, 48 Vibrating body 13, 44, 45 Partition 14 Channel 15a, 15b Hole 16a Lower glass substrate 16b Upper glass substrate 17 Through-hole 18 Titanium film 21 Center part 22 Beam part 23 Ring part 24 Drive electrode 25 Detection electrode 26 DC power supply 27 AC power supply 31 Stage 32 Table 33 Network analyzer 34 Probe 35 Laser control part 36 Laser oscillator 37 Measurement control part 38 Storage part 39 Computer 40 Determination unit 100, 300 Getter evaluation apparatus 200 Getter evaluation system

Claims (5)

One sealed space,
A getter disposed in the sealed space;
One or more other sealed spaces that are connected to the sealed space through a flow path having a partition wall and in which a gas that can be absorbed by the getter is sealed;
A vibrating body formed in each of the sealed spaces,
An apparatus for evaluating a getter that allows the gas to flow into a sealed space in which the getter is disposed by removing at least a part of the partition wall using a laser. The getter evaluation apparatus according to claim 1, wherein at least a part of a portion of the flow path from the partition wall to a sealed space where the getter is disposed has a zigzag shape or a meandering shape. Two glass materials having a hollow portion are production substrates of the MEMS device including a plurality of sealed spaces formed by sandwiching a silicon substrate on which a MEMS device using a vibrating body is formed,
A MEMS device production substrate comprising the getter evaluation apparatus according to claim 1 on at least a part of the substrate. One sealed space, a getter disposed in the sealed space, and another one that is connected to the sealed space via a flow path having a partition and is filled with a gas that can be absorbed by the getter Alternatively, a stage on which a getter evaluation device including a plurality of sealed spaces and a vibrating body formed in each of the sealed spaces is mounted;
A laser oscillator having an output for removing and penetrating at least part of the partition;
A laser controller for controlling the irradiation condition of the laser irradiated by the laser oscillator;
It said first vibrator of Q value getter formed arranged sealed space (hereinafter referred to as Q ₁ value), the vibrating body the gas is formed in at least one sealed space is enclosed ( hereinafter, Q value of the generic and the second vibrator to) (hereinafter referred to as Q ₂ values collectively), and the first vibrating body after penetration by removal of at least a portion of said partition wall or said second A measuring instrument for measuring the Q value of the vibrating body (hereinafter collectively referred to as Q ₃ value);
A measurement controller for controlling the measuring instrument;
A storage unit for storing the Q ₁ value, the Q ₂ value, and the Q ₃ value;
A getter evaluation system comprising a calculation device that calculates a gas absorption amount by a getter from the Q ₁ value, the Q ₂ value, and the Q ₃ value. The measuring instrument measures Q values of the first vibrating body and the second vibrating body after being penetrated by removing at least a part of the partition wall.
The getter evaluation system according to claim 4 .

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