Chambers and Probers

Abstract

The temperature of the observation window is reduced. [Solution] The apparatus includes a stage 8 for fixing an evaluation object 110, a heater 30 for heating the stage 8, airtight containers 10, 20 for housing the heater 30 and the stage 8, and a first cooling pipe 7 for cooling the sidewalls of the airtight containers 10, 20, the airtight containers 10, 20 including a main body 10 surrounding the heater 30 and the stage 8, and an observation section 20 having an observation window 18 for observing the evaluation object 110, the observation section 20 protruding from the main body 10. The apparatus also includes a second cooling pipe 17 for cooling the sidewalls of the observation section 20.

Description

[Technical field]

[0001] The present invention relates to a chamber and a prober, for example, to a vacuum chamber and a prober for evaluating high temperature device characteristics in a vacuum. [Background technology]

[0002] In highly integrated semiconductor devices, the scattering of heat-carrying phonons increases thermal resistance, making heat dissipation difficult. For this reason, new heat dissipation mechanisms and materials are required to improve performance. Non-Patent Document 1 discloses that the thermal conductivity of silicon nitride thin films can be doubled by using surface phonon polaritons, which are a mixture of light and phonons.

[0003] In this non-patent document 1, the thermal conductivity of the semiconductor device is evaluated up to a maximum temperature of 800 K. In order to evaluate the semiconductor device at a higher temperature, the chamber needs to be constructed so as to withstand the high temperature.

[0004] Patent Document 1 discloses a low-pressure CVD (Chemical Vapor Deposition) device that employs a cold wall (water-cooled chamber). Patent Document 2 discloses a prober that has a heat insulating part that insulates the connection part between the head stage and the card holder, and a heater that heats the wafer chuck, and that controls the temperature of the head stage to be the ambient temperature. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Japan Science and Technology Agency (JST), University of Tokyo, “Doubling the thermal conductivity of silicon nitride thin film with light ~ A new heat dissipation mechanism that leads to improved performance of semiconductor devices ~”, [Search date 2024.11.11], Internet<URL:https: / / www.jst.go.jp / pr / announce / 20201001 / pdf / 20201001.pdf> [Patent documents]

[0006] [Patent Document 1] JP 2000-323465 A (Figures 3-6, paragraphs 0006 and 0029) [Patent Document 2] JP 2012-178599 A (Abstract, paragraphs 0024, 0025, 0032) Summary of the Invention [Problem to be solved by the invention]

[0007] Probers often take images of semiconductor devices with an imaging camera to position the electrodes of the semiconductor devices and the measurement probes. When the semiconductor devices are heated to high temperatures to evaluate their characteristics, it is necessary to image the semiconductor devices from outside the chamber through an observation window (transparent medium). The low-pressure CVD apparatus described in Patent Document 1 does not have an observation window. The technology described in Patent Document 2 does not have a chamber. Even if the inventions described in Patent Documents 1 and 2 are combined, the heater described in Patent Document 2 does not reach a temperature high enough to cause cracking of the observation window.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a chamber and a prober capable of reducing the temperature of the observation window. [Means for solving the problem]

[0009] In order to achieve the above object, the chamber (100) of the first invention includes a stage (8) for fixing an evaluation object (110), a heater (30) for heating the stage, an airtight container (main body 10, observation unit 20) for accommodating the heater and the stage, and a first cooling pipe (7) for cooling the side wall of the airtight container, and the airtight container includes a main body surrounding the heater and the stage, and an observation window (18) for observing the evaluation object. is fixed The observation unit (20) The observation section (20) has a side wall (a side wall of the cylindrical body 11)protruding from the main body portion 10. Note that the symbols and letters in parentheses are symbols and the like given in the embodiment and do not limit the present invention.

[0010] The chamber of the second invention comprises a stage for fixing an object to be evaluated, a heater for heating the stage, an airtight container for accommodating the heater and the stage, and a first cooling pipe for cooling a side wall of the airtight container, and the airtight container comprises a main body portion surrounding the heater and the stage, and an observation portion having an observation window for observing the object to be evaluated and a cylindrical body for fixing the observation window, and the cylindrical body protrudes from the main body portion. Effect of the Invention

[0011] According to the present invention, the temperature of the observation window can be reduced. [Brief description of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view of a prober according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a top view of a chamber according to an embodiment of the present invention. [Diagram 3] 2 is a view taken along the line AA of the prober (FIG. 1) according to the embodiment of the present invention. [Figure 4] FIG. 4 is a diagram for explaining a heat flow in a chamber according to an embodiment of the present invention. [Diagram 5] 1 is a cross-sectional view of a probe used in a prober according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention (hereinafter, referred to as "the present embodiment") will be described in detail with reference to the drawings. Note that each drawing is merely a schematic illustration to allow a sufficient understanding of the present embodiment. In addition, in each drawing, common or similar components are given the same reference numerals, and duplicated explanations thereof will be omitted.

[0014] FIG. 1 is a cross-sectional view of a prober according to an embodiment of the present invention. The X, Y, and Z directions follow the arrows in the figure, with the Z direction being the upward direction and the Y direction being perpendicular to the plane of the paper in FIG. The prober 1000 is composed of a chamber 100, a probe 200, and a camera 310 and a lens 315 indicated by dashed lines. The prober 1000 is an apparatus that heats an evaluation object 110 to a high temperature (e.g., 1200 K) in the sealed space of the chamber 100 and measures the electrical characteristics of the heated evaluation object 110 with the probe 200. The evaluation object 110 is, for example, a thin-film semiconductor device having a thickness of 50 nm or less.

[0015] In many materials, phonons are mainly responsible for thermal conduction, and the thermal conductivity decreases as the temperature rises. For example, the thermal conductivity of a 200 nm-thick thin film decreases with the square of the temperature. However, when the thickness is reduced to about 100 nm, the tendency for the thermal conductivity to decrease weakens, and when the thickness is further reduced to 50 nm or less, the thermal conductivity increases. The prober 1000 of this embodiment can perform device evaluation of this phenomenon. This leads to easy thermal design of semiconductor devices that takes the film thickness into account.

[0016] The chamber 100 includes a stage 8, a main body 10, an observation unit 20, and a heater 30. The main body 10 surrounds the stage 8 and the heater 30. The stage 8 is a chuck that fixes the evaluation object 110, and is disposed adjacent to the heater 30. The observation unit 20 observes the evaluation object 110 using a camera 310 and a lens 315. The camera 310 and the lens 315 are also used to position the probe 200 relative to the evaluation object 110.

[0017] The main body 10 and the observation unit 20 are formed of a metal medium (e.g., aluminum that has been black anodized). The main body 10 and the observation unit 20 are internally connected to each other, forming an airtight container that houses the heater 30 and the stage 8. The internal space is maintained in a vacuum or filled with a gas (e.g., oxygen or an inert gas). The nozzle 40 is a gas outlet that sprays a gas (e.g., oxygen) onto the evaluation object 110.

[0018] The main body 10 includes a cylindrical body 1, a flange 2, a base 3 (3a, 3b), an exhaust system chamber 4, a plurality (six) of first measuring chambers 5, a second measuring chamber 6 (FIGS. 2, 3), and a first cooling pipe 7. The flange 2 is disposed on the upper part of the cylindrical body 1. The observation part 20 is joined to the flange 2. The base 3 fixes the cylindrical body 11 and holds a support member 35 located at the lower part of the heater 30. The inner surface 1a of the cylindrical body 1 and the heater 30 are separated by a gap d1. The base 3 is composed of two bases 3a, 3b. The flange 2 and the base 3a are so-called ICF (I Conflat Flange) flanges.

[0019] The exhaust chamber 4 functions as an exhaust port for evacuating the internal space of the chamber 100. After the exhaust chamber 4 is evacuated, it also functions as a gas inlet port for introducing a gas (e.g., oxygen) necessary for evaluation of the evaluation object at an appropriate concentration. At the end of the exhaust chamber 4, a KF (Kleinflansch) flange 4a is formed.

[0020] The measuring chambers 5 and 6 are chambers into which a probe 200, a thermocouple, etc. are inserted. A JIS flange 5a is formed at an end of the first measuring chamber 5. An ICF flange 6a is formed at an end of the second measuring chamber 6. The KF flange 4a of the exhaust system chamber 4 and the JIS flange 5a of the measuring chamber 5 are connected to a chamber or a sealing plate (not shown). This allows the chamber 100 to function as an airtight chamber or a vacuum chamber.

[0021] The first cooling pipe 7 is wound around the side wall of the cylindrical body 1 multiple times (for example, 6 to 7 times) and is welded to the cylindrical body 1. Cooling water flows through the first cooling pipe 7 to cool the cylindrical body 1.

[0022] The heater 30 includes a SiC heater 31, two electrodes 32, a water-cooled pipe 33, a heat shield 34, and a support member 35. The SiC heater 31 heats the evaluation object 110 to a high temperature of up to 1200K in a vacuum. In addition, since the SiC heater 31 has a property that SiC does not react with gas, the evaluation object 110 can be heated to 1000K even when oxygen is blown. The electrodes 32 are connected to the SiC heater 31. The heat shield 34 blocks the heat generated by the SiC heater 31 and reduces the temperature rise of the support member 35. The support member 35 is fixed to the base 3. The heat conductive member 36 is a metal member that dissipates the heat generated by the SiC heater 31 to the base 3 (3a, 3b) via the support member 35. It should be noted that the heat conducting member 36 does not need to cover the entire side surface of the heater 30, and may be made of a plurality of plate members. Also, the heat conducting member 36 may be made of a plurality of columnar members.

[0023] The observation section 20 is configured with a cylinder 11, flanges 12 and 13, an observation window fixing member 14, a second cooling pipe 17, and an observation window 18. The cylinder 11 is cylindrical, and flanges 12 and 13 are fixed to its ends. A flange 2 of the main body 10 is attached to the flange 12, and the cylinder 11 and the cylinder 1 of the main body 10 are connected to each other. In other words, the chamber 100 is provided with an airtight container in which the observation section 20 protrudes from the main body 10. The observation window fixing member 14 is configured with two ring-shaped plates 14a and 14b. The plates 14a and 14b are fixed to the flange 13 with a circular plate (observation window 18) sandwiched in the recess 14c.

[0024] The second cooling pipe 17 is wound around the side wall of the cylindrical body 11 multiple times (for example, twice) and welded to the cylindrical body 11. Cooling water flows through the second cooling pipe 17 to cool the cylindrical body 11. The first cooling pipe 7 and the second cooling pipe 17 may be connected to each other or may be independent. Furthermore, the first cooling pipe 7 and the second cooling pipe 17 may have the same diameter or different diameters.

[0025] The observation window 18 is a plate material of a light-transmitting medium (for example, synthetic quartz). Synthetic quartz is more heat-resistant than glass. The observation window 18 is fixed to the upper end of the cylinder 11 using the observation window fixing member 14 (plate materials 14a, 14b). The camera 310 and the lens 315 capture the evaluation object 110 from outside the chamber 100 through the observation window 18. The lens 315 is preferably a long-acting objective lens. Thereby, the end of the lens 315 is positioned so that the distance to the evaluation object 110 is the working distance WD. In addition, a predetermined distance d2 is maintained between the end of the lens 315 and the surface (outer surface) of the observation window 18. In other words, the distance between the surface (outer surface) of the observation window 18 and the evaluation object 110 is less than the working distance WD of the lens 315.

[0026] FIG. 2 is a top view of the chamber 100 of the present embodiment. Each of the multiple measuring chambers 5, 6 and the exhaust system chamber 4 radially protrudes or extends from the side of the cylindrical body 1 (FIG. 1) at an equal angle of 45 degrees to the adjacent chambers. A rectangular evaluation object 110 can be seen through an observation window 18 at the center of the flange 12 and the plate material 14b.

[0027] FIG. 3 is a view taken along the line AA of the prober (FIG. 1) according to the embodiment of the present invention. 2, each of the multiple measuring device chambers 5, 6 and the exhaust system chamber 4 protrudes or extends radially from the side surface of the cylindrical body 1 at an equal angle of 45 degrees to the adjacent chambers. In the center of the cylindrical body 1, a heater 30 equipped with a circular stage 8 and a rectangular evaluation object 110 fixed to the stage 8 are disposed.

[0028] FIG. 4 is a diagram for explaining the heat flow in the chamber 100 according to the embodiment of the present invention. The heat flow is generated by thermal conduction in which heat is conducted through metal media such as the cylinders 1 and 11, heat transfer in which convection of the gas sealed in the chamber moves heat, and heat radiation from a heat generating medium (for example, heater 30 such as SiC heater 31). If the internal space is a vacuum chamber (vacuum chamber), heat transfer does not occur and the heat flow is generated only by thermal conduction and thermal radiation.

[0029] Here, the heat flow from the heat generated by the heater 30 to the observation window 18 located above will be described. An inner surface 1a (FIG. 1) of the cylindrical body 1 and a side surface of the heater 30 are separated by a gap d1 (FIG. 1). The heater 30 includes a SiC heater 31, a heat shield 34, a support member 35, and a heat conductive member 36, and is fixed to a base 3 by the support member 35. Therefore, heat flows 401 and 403 flowing out from the SiC heater 31 reach the cylindrical body 1 via the heat conductive member 36, the support member 35, and the base 3. Heat flows 402 and 404 that reach the cylindrical body 1 reach an outer circumferential portion 18a of the observation window 18 via the flanges 2 and 12, the cylindrical body 11, and the flange 13.

[0030] Furthermore, the SiC heater 31 and the heated evaluation object 110 generate heat flows 405, 406, and 406 due to thermal radiation. The heat flow 405 radiates in the Z direction perpendicular to the radiation surface (XY plane) of the SiC heater 31 and the evaluation object 110, and reaches the observation window 18. The observation window 18 transmits visible light but easily absorbs infrared light and generates heat. The heat flows 406 and 406 radiate at an angle to the radiation surface, and reach, for example, the inner surface 11a of the cylindrical body 11. The inner surface 11a of the cylindrical body 11 is, for example, black anodized, and therefore easily absorbs heat.

[0031] If the cylindrical body 11 is not provided and the observation window 18 is disposed at the flange 2, the distance between the end (upper end) of the cylindrical body 1 and the observation window 18 is shortened. Since the observation window 18 is made of synthetic quartz, it is subject to conductive heat from the cylindrical body 1 and radiant heat from the SiC heater 31 of the heater 30, and is prone to cracking due to thermal distortion. In contrast, since the present embodiment has the cylindrical body 11 with a length L, the distance (projection length) between the end of the cylindrical body 1 and the observation window 18 is long. As a result, the thermal resistance increases by the cylindrical body 11, and the temperature of the observation window 18 decreases. As a result, the observation window 18 is less likely to crack in the chamber 100 of this embodiment than in a chamber in which the observation window 18 is not spaced apart from the flange 2. In other words, the chamber 100 of this embodiment can be heated to a higher temperature by the heater 30 than in a chamber in which the observation window 18 is not spaced apart from the flange 2.

[0032] Furthermore, in this embodiment, the second cooling pipe 17 is wound around the cylindrical body 11. Therefore, the temperature of the observation window 18 is further reduced, and the observation window 18 is less likely to crack. Note that the protruding length of the observation window 18 is limited by the working distance WD of the lens 315 while the second cooling pipe 17 needs to be able to be wound around it.

[0033] (probe) FIG. 5 is a cross-sectional view of a probe 200 used in the prober 1000 (FIG. 1) according to an embodiment of the present invention. The probe 200 is used by being inserted into the measuring device chamber 5 (FIG. 1). The probe 200 includes a connector 201, a core wire 202, a holder 203, a metal tube 204, an alumina bushing 205, a probe fixing plate 206, a sealing material 207, and a probe needle 208.

[0034] The connector 201 is a receptacle of a general-purpose SMA (Sub Miniature Type A) connector. A coaxial cable with a plug (not shown) is connected to the connector 201. The core wire 202 is a metal wire of nickel (Ni), and one end 202a is connected to an electrode (terminal) formed on the receptacle. The holder 203 fixes the connector 201 and one end 204a of the metal tube 204. The metal tube 204 has an outer diameter φ1 and an inner diameter φ2, and the core wire 202 is inserted without contact and shielded. In other words, the metal tube 204 and the core wire 202 form a coaxial line. The alumina bush 205 is a plate material (insulating member) made of alumina (insulating material), and fixes the other end 204b of the metal tube 204 and the other end vicinity 202b of the core wire 202. The probe fixing plate 206 is a metal plate that fixes the other end 202c of the core wire 202 and the probe needle 208. When the core wire 202 is longer than the metal tube 204 by a predetermined length or more, the probe fixing plate 206 is fixed in a predetermined position. The sealing material 207 is a gasket or an O-ring, and seals the gap between the connector 201 and the holder 203. The probe needle 208 is a metal needle, and comes into contact with the evaluation object 110.

[0035] As described above, in the probe 200 of this embodiment, the tip portion (near the other end 202b) of the core wire 202 and the tip portion (other end 204b) of the metal tube 204 are fixed by the alumina bushing 205, which is an insulating member. Incidentally, it is conceivable to insulate the tip portion of the core wire 202 and the tip portion of the metal tube 204 with fluororesin. Since the melting point of fluororesin is about 300°C, the evaluation object 110 (FIG. 1) can be heated to a high temperature of 300°C or more by insulating with the metallic alumina bushing 205. In other words, the prober 1000 of this embodiment can heat the evaluation object 110 to a temperature higher than the melting point of the fluororesin by using the probe 200.

[0036] (Modification) The present invention is not limited to the above-described embodiment, and various modifications are possible, for example, as follows. (1) In the above embodiment, the first cooling pipe 7 is wound around the cylindrical body 1, and the second cooling pipe 17 is wound around the cylindrical body 11. However, it is not necessary to wind either or both of the first cooling pipe 7 and the second cooling pipe 17. As long as the temperature of the observation window 18 is reduced by the thermal resistance of the cylindrical body 11, it is sufficient that the chamber has an airtight container in which the observation unit 20 having the observation window 18 protrudes from the main body 10 (flange 2).

[0037] In other words, even when a chamber in which the observation portion does not protrude from the main body portion 10 is used and the object to be evaluated 110 is heated to a high temperature that would cause the observation window 18 to crack, the protrusion of the observation portion 20 prevents the observation window 18 from cracking.

[0038] (2) In the above embodiment, the observation unit 20 protrudes from the main body 10, but it is not necessary to have it protrude. In other words, it is not necessary to provide the cylinder 11 and the second cooling pipe 17. That is, it is sufficient that the main body 10 is provided with a base 3 that supports the heater 30 and the stage 8, the side wall of the cylinder 1 and the heater 30 are spaced apart, and the observation window 18 is attached to the flange 2. As a result, the heat generated by the heater 30 is thermally conducted to the observation window 18 via the base 3, the cylinder 1, and the flange 2.

[0039] (3) The main body 10 and the observation section 20 of the airtight container are configured with the cylinders 1, 11 that are circular in cross section, but may be rectangular or square in cross section. In the prober 1000 of the above embodiment, the gap d1 (FIG. 1) between the cylinder 1 and the heater 30 is short, so the probe 200 is inserted into the measuring device chambers 5, 6. When the cylinder 1 is much larger than the heater 30, the probe can be disposed inside the cylinder 1 without providing the measuring device chambers 5, 6.

[0040] (4) In the above embodiment, in order to capture an image of evaluation object 110 perpendicular to the mounting surface of stage 8, the optical axis of camera 310 and lens 315 was perpendicular to the mounting surface of stage 8. Therefore, observation window 18 and the mounting surface of stage 8 were parallel. When observing evaluation object 110 obliquely, observation window 18 and the mounting surface of stage 8 may be inclined. [Explanation of symbols]

[0041] 1 cylinder 3,3a,3b base 4 Exhaust system chamber 5,6 Measuring instrument chamber 7 First cooling pipe 8 stages (chucks, substrate holders) 10 Main body (airtight container) 11 Cylinder (side wall) 14 Observation window fixing member 17 Second cooling pipe 18 Observation window 20 Observation section (extension section, airtight container) 30 Heater 31 SiC heater 35 Support member (bottom) 36 Thermal Conductive Materials 100 Chamber (Airtight Chamber) 110 Evaluation Object 200 Probes 202 Core wire (Ni wire) 204 Metal tube 205 Alumina bush (insulating material) 208 Probe Needle 315 Lens 1000 Prober

Claims

1. a stage for fixing an evaluation object; A heater for heating the stage; an airtight container that houses the heater and the stage; a first cooling pipe for cooling a side wall of the airtight container; the airtight container includes a main body portion surrounding the heater and the stage, and an observation portion to which an observation window for observing the evaluation object is fixed, The observation section has a side wall protruding from the main body. A chamber characterized by:

2. The first cooling pipe cools a side wall of the main body, A second cooling pipe is provided to cool the side wall of the observation section.

2. The chamber of claim 1.

3. A stage for fixing an object to be evaluated; A heater for heating the stage; an airtight container that houses the heater and the stage; a first cooling pipe for cooling a side wall of the airtight container; the airtight container includes a main body surrounding the heater and the stage, and an observation unit having an observation window for observing the evaluation object and a cylinder for fixing the observation window; The cylindrical body protrudes from the main body. A chamber characterized by:

4. A prober having a chamber described in any one of claims 1 to 3.

5. The airtight container further includes a probe housed therein, the probe includes a core wire, a metal tube into which the core wire is inserted without contact, and an insulating member that insulates a tip end of the core wire from a tip end of the metal tube; The insulating member is made of alumina.

5. The prober according to claim 4.

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