JP2006237059A - Depressurization heating measurement instrument for semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a depressurization heating measurement instrument for a semiconductor element capable of highly accurate measurement by reducing an electric noise and a leak current. <P>SOLUTION: The instrument is provided with a chamber 2 capable of arranging a semiconductor element 15 at a predetermined position; a specimen stage 3 capable of arranging the semiconductor element 15 at the predetermined position in advance; heating mechanism capable of adjusting the temperature of the semiconductor element 15 arranged at the predetermined position on the specimen stage 3 at a previously decided temperature; pump 6 capable of depressurizing the inside of the chamber 2; gas introducing system 7 for introducing an inert gas into the chamber 2; and conductance valve 8 being a pressure adjusting mechanism of a gas including the inert gas in the chamber 2. The instrument has a configuration in which the specimen stage 3 and the semiconductor element 15 are heated in the chamber 2 which is vacuum or filled with the inert gas and depressurized in its inside. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a reduced pressure heating measuring apparatus for a semiconductor element, in which a semiconductor element having an insulating film or a metal film is heated in vacuum or under reduced pressure in which an inert gas flows to measure characteristics.

Conventionally, when measuring characteristics of a semiconductor device at a high temperature or low temperature, generally, a method of measuring the semiconductor device in a vacuum or under a reduced pressure in which an inert gas such as a rare gas or nitrogen gas is flown is used. .
As a result, when heating or cooling is performed at atmospheric pressure, the characteristics of the semiconductor element deteriorate due to a chemical reaction between the substance constituting the semiconductor element and impurities present in the atmosphere, or the heating unit is oxidized or carbonized. This prevents the measurement itself from becoming impossible due to a decrease in the heating capacity due to or abnormal heating or condensation of the semiconductor element and the measuring device.

  For this reason, when measuring a semiconductor element in a high temperature or low temperature state, it is required to perform in a vacuum or under reduced pressure with an inert gas flow.

As a reduced pressure heating measuring apparatus for semiconductor elements, there is one that allows a processing gas to flow in a vacuum measuring apparatus (for example, Patent Document 1).
JP 2004-31881 A

  However, when heating a semiconductor element in a vacuum or under reduced pressure with an inert gas flow, as in the reduced pressure heating measurement apparatus for semiconductor elements described in Patent Document 1, the following problems can be cited. Measurement of electrical characteristics may be difficult.

  When heating a semiconductor element having a large surface area, a heating unit having an area larger than the surface area of the semiconductor element is required. Along with this, there is a problem that the heat capacities of the heating unit and the sample stage are increased, and the temperature rising and cooling time becomes long.

  Further, when the temperature is high, the conductivity of the insulating member or the like increases, and thus there is a possibility that the measurement value error becomes large.

  Moreover, the thermoelectrons etc. emitted from the heating unit may flow into the copper wire or the sample stage, thereby causing a measurement value error.

  Further, heating to a high temperature causes thermal expansion of the members constituting the heating unit and the sample stage, and it becomes difficult to maintain the mechanical accuracy of these components, such as flatness. For this reason, there exists a possibility that the temperature uniformity in the heating surface of a semiconductor element may fall or it may lead to a fatal destruction of a measuring apparatus.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a reduced pressure heating measurement apparatus for semiconductor elements that can reduce electrical noise and leakage current and can perform highly accurate measurement.

In order to solve the above-mentioned problems, the present invention provides a reduced pressure heating measuring apparatus for semiconductor elements having the following configuration.
(1) Invention of Claim 1 The chamber which can arrange | position a semiconductor element in a predetermined position, the sample stage which can arrange | position the said semiconductor element beforehand in a predetermined position, and the predetermined position on this sample stage A heating mechanism capable of adjusting the disposed semiconductor element to a predetermined temperature; a vacuum exhaust system capable of reducing the pressure in the chamber; and a gas introduction system for introducing an inert gas into the chamber; A pressure adjusting mechanism for a gas containing an inert gas in the chamber, the sample stage and the semiconductor element are heated under vacuum or a reduced pressure filled with an inert gas, and the sample An order of measurement accuracy when a current value flowing in the semiconductor element through the stage is measured is 1 nA (1 × 10 −9 A) or less. Semiconductor element heating under reduced pressure measuring device.
(2) The invention according to claim 2 is characterized in that it measures a semiconductor element having a single layer film made of an insulating film or a metal film, or a composite film made of at least two of these. The reduced-pressure heating measuring apparatus for semiconductor elements according to claim 1.
(3) Invention of Claim 3 The said heating mechanism consists of the heater which consists of an alloy which consists of chromium, aluminum, and iron, platinum, nichrome, or tungsten, and is accommodated in the heating unit. 3. The reduced pressure heating measuring apparatus for a semiconductor element according to claim 1, wherein the heating unit is arranged to be electrically insulated from the sample stage.
(4) The invention according to claim 4, further comprising a thermoelectron shield portion that shields thermoelectrons generated from the heating mechanism, wherein the thermoelectron shield portion is grounded at any location of the chamber. The reduced pressure heating measuring apparatus for semiconductor elements according to any one of claims 1 to 3.
(5) Invention of Claim 5 The said thermoelectron shield part consists of carbon or a metal net | network, The vacuum heating measuring apparatus for semiconductor elements of Claim 4 characterized by the above-mentioned.
(6) Invention of Claim 6 The lower insulation member which electrically insulates between the said heating mechanism and the said sample stage is provided, In any one of Claims 1-5 characterized by the above-mentioned. The vacuum heating measuring apparatus for semiconductor elements as described.
(7) Invention of Claim 7 The said lower insulating member consists of quartz or a ceramic, The vacuum heating measuring apparatus for semiconductor elements of Claim 6 characterized by the above-mentioned.
(8) The invention according to claim 8, wherein the lower insulating member is provided with a transmission hole, a susceptor is attached to the transmission hole, and the susceptor is heated by infrared radiation of the heating mechanism, 8. The semiconductor device reduced pressure heating measurement apparatus according to claim 7, wherein a temperature sensor is provided at any location of the susceptor.
(9) Invention of Claim 9 The said susceptor consists of carbon, The vacuum heating measuring apparatus for semiconductor elements of Claim 8 characterized by the above-mentioned.
(10) The invention according to claim 10, wherein an electrically insulating upper insulating member is disposed above the susceptor, and the sample stage is disposed above the upper insulating member. 9. A vacuum heating measuring apparatus for semiconductor elements according to 9.
(11) Invention of Claim 11 The said upper insulation member consists of at least 1 or more materials among an alumina, sapphire, and quartz, The vacuum heating measuring apparatus for semiconductor elements of Claim 10 characterized by the above-mentioned.
(12) Invention of Claim 12 The said sample stage consists of at least 1 or more materials among molybdenum, nickel, a tantalum, and tungsten, The structure of any one of Claims 1-11 characterized by the above-mentioned. Vacuum heating measuring device for semiconductor elements.
(13) Invention of Claim 13 The sample stage forms a measurement electrode of the semiconductor element when the semiconductor element is arranged. In any one of claims 1 to 12, The vacuum heating measuring apparatus for semiconductor elements as described.
(14) Invention of Claim 14 The said heating unit and the said sample stage are installed on the conveyance stage which can be driven by an X-axis, a Y-axis, and (theta) axis | shaft of Claims 3-13 The reduced-pressure heating measuring apparatus for semiconductor elements according to any one of the above.
(15) The invention according to claim 15 The probe card or micro prober which contacts the semiconductor element from above the sample stage is provided in the vicinity of the sample stage. The reduced pressure heating measuring apparatus for semiconductor elements described in 1.

According to the reduced pressure heating measurement apparatus of the present invention, a chamber in which a semiconductor element can be placed in a predetermined position, a sample stage in which the semiconductor element can be placed in a predetermined position, and a predetermined position on the sample stage A heating mechanism capable of adjusting the semiconductor element disposed in a predetermined temperature, a vacuum exhaust system capable of depressurizing the chamber, and a gas introduction system for introducing an inert gas into the chamber. And a pressure adjusting mechanism for a gas containing an inert gas in the chamber, and the sample stage and the semiconductor element are heated with the inside of the chamber under vacuum or under reduced pressure filled with an inert gas, The order of measurement accuracy when the value of the current flowing through the semiconductor element through the sample stage is measured is 1 nA (1 × 10 −9 A) or less. It has a reduced construction electrical noise and leakage current.
Accordingly, it is possible to realize a reduced pressure heating measuring apparatus for semiconductor elements with a short temperature rising and cooling time and high measurement accuracy.
In addition, according to the reduced pressure heating measuring apparatus of the present invention, the heating unit and the sample stage are separated from each other, thereby suppressing the mechanical deformation and electrical noise generated by the heater heating from affecting the sample stage. Yes.
Therefore, it is possible to realize a reduced pressure heating measuring apparatus for semiconductor elements with high measurement accuracy with a simple configuration.

Embodiments of a reduced pressure heating measuring apparatus for semiconductor elements according to the present invention will be described below with reference to the drawings.
FIG. 1 and FIG. 2 are schematic views showing a reduced pressure heating measuring device for semiconductor elements of this embodiment, and this reduced pressure heating measuring device for semiconductor elements (hereinafter sometimes abbreviated as reduced pressure heating measuring device) 1 is The chamber 2, the sample stage 3 on which the semiconductor element 15 can be arranged in advance at a predetermined position, and the heating mechanism 5 that can adjust the semiconductor element 15 arranged on the sample stage 3 to a predetermined temperature. A pump (evacuation system) 6 for reducing the pressure in the chamber 2, a gas introduction system 7 for introducing an inert gas into the chamber 2, and a conductance valve (pressure) for the gas containing the inert gas in the chamber 2 And an adjustment mechanism) 8. In FIG. 2, the principal part of the hot chuck mechanism which comprises the pressure reduction heating measuring apparatus 1 of this embodiment is shown.
With the above-described configuration, the reduced-pressure heating measurement apparatus 1 heats the sample stage 3 and the semiconductor element 15 with the inside of the chamber 2 under a vacuum or a reduced pressure filled with an inert gas, and enters the semiconductor element 15 via the sample stage 3. The order of measurement accuracy when the flowing current value is measured is 1 nA (1 × 10 −9 A) or less.

  In the reduced pressure heating measuring apparatus 1, the heating mechanism 5 includes a heater 51 and is accommodated in the heating unit 4, and the heating unit 4 is electrically insulated from the sample stage 3. ing

  The semiconductor element 15 measured by the reduced pressure heating measuring apparatus 1 of the present embodiment has a single layer film 15a made of an insulating film or a metal film, or a composite film 15b made of at least two of these, Arranged on the upper surface 31 of the sample stage 3.

The chamber 2 is a container configured with a sealed structure, and serves as a measurement chamber when the characteristics of the semiconductor element 15 are measured.
The chamber 2 is configured to be depressurized by a pump 6 described later.

The sample stage 3 functions as a mounting table on which the semiconductor element 15 is disposed on the upper surface 31 when performing characteristic measurement using the reduced pressure heating measurement apparatus 1.
The material of the sample stage 3 is selected from a refractory metal material having a small thermal expansion coefficient such as nickel, molybdenum, etc., for example, so that even if the sample stage 3 is heated to a high temperature, Flatness and mechanical processing accuracy can be maintained.
In the example shown in FIG. 2, when the semiconductor element 15 as the object to be measured is placed on the sample stage 3, it is fixed to the upper surface 31 using the presser fitting 32, but is not limited to the illustrated example. A configuration for fixing the semiconductor element 15, such as mounting and fixing the semiconductor element 15 by providing a recessed portion, may be appropriately selected and adopted.

As shown in FIG. 2, the heating unit 4 includes a heating mechanism 5 accommodated in a case 4a formed in a box shape with an upper surface opened, and a columnar transfer stage connecting jig extending through the bottom surface of the case 4a. 41 extends downward, and a transfer stage mounting portion 42 is provided at the lower end of the transfer stage 41.
A lower insulating member 43 is attached to the opening 4b of the case 4a along the edge of the opening 4b, and a transmission hole 43a is provided at the center of the lower insulating member 43. A susceptor 44 is attached to the transmission hole 43a so as to cover the opening 4b so that the peripheral edge thereof is supported by the lower insulating member 43. An upper insulating member 45 is disposed above the susceptor 44 so as to be interposed between the susceptor 44 and the sample stage 3.

The heating mechanism 5 heats the semiconductor element 15 when the characteristics of the semiconductor element 15 are measured. In the example shown in FIG. 2, the heater cover 52 surrounds the heater 51 that is a heat source. And is accommodated in the case 4 a of the heating unit 4.
In the illustrated example, the heater 51 is supported by one end of the transfer stage connecting jig 41 and is surrounded by a heater cover 52 that is formed in a box shape on the side and below, and is formed in an opening 52 a above the heater cover 52. Is attached so that the thermionic shield 53 covers it.
As a material constituting the heater 51, for example, a material generally used as a heater material, such as an alloy made of chromium, aluminum, and iron (for example, Sandvik Co., Ltd .: Kanthal (registered trademark)), platinum, nichrome, tungsten, or the like. In this embodiment, the heating operation is performed by infrared radiation. In addition, when using the alloy which consists of the above-mentioned chromium, aluminum, and iron, it is heating efficiency to use the alloy of the component ratio which consists of Cr: 22%, Al: 5.3-5.8%, and the remainder is Fe. Etc. are preferable.
The shape of the heater 51 can be appropriately determined using the above-described materials, but may be configured to increase the heat generation efficiency by, for example, winding in a coil shape.
The thermoelectron shield 53 is formed in a net shape with a carbon material or a metal material, and transmits infrared rays emitted from the heater 51 while shielding thermoelectrons emitted from the heater 51. The thermoelectron shield 53 is grounded to the chamber 2, for example, to reduce electrical noise when measuring the characteristics of the semiconductor element 15 with the reduced pressure heating measuring device 1 and maintain the electrical noise characteristics in a good state. Measurement can be performed.
The mesh of the thermionic shield 53 is formed with a fineness of about 0.1 to 3 mm, and the thickness is in the range of 0.4 to 0.8 mm. This is preferable in terms of heating efficiency and electrical noise blocking.

As shown in FIG. 1, the heating unit 4 in which the heating mechanism 5 is accommodated is installed on a transfer stage 9 provided in the chamber 2. As shown in FIG. 2, at this time, the heating unit 4 is supported by the transfer stage connecting jig 41 and is installed between the transfer stage mounting portion 42 and the transfer stage 9 via an insulator such as ceramic.
The transfer stage 9 is configured to be movable in the X-axis, Y-axis, and θ-axis directions in the chamber 2 by a driving unit (not shown).
With the above-described configuration, the heating unit 4 is disposed so as to be electrically insulated from the sample stage 3.

The susceptor 44 is made of a carbon material or the like excellent in thermal conductivity and mechanical processing accuracy, and is provided with a temperature sensor 44a made of a thermocouple or the like so as to be embedded in the outer peripheral portion of the susceptor 44.
The susceptor 44 is irradiated with infrared rays emitted from the heater 51 serving as a heat source and transmitted through the thermoelectron shield 53. The susceptor 44 absorbs infrared rays and can be heated to 800 ° C. in a reduced-pressure inert gas atmosphere. It has become.
Further, the temperature of the susceptor 44 heated by the heater 51 can be detected by a temperature sensor 44a, and the temperature can be controlled by a control means (not shown).

As shown in FIG. 1, the pump 6 is connected to the chamber 2 via a conductance valve 8 described later, and evacuates the chamber 2.
For example, a vacuum pump such as a rotary pump or a dry pump can be used as the pump 6.
With the above-described configuration, the pump 6 reduces the pressure in the chamber 2 to a pressure of 10 ⁻¹ Pa or less, and the pressure in the chamber 2 can be adjusted by a conductance valve 8 described later.

The gas introduction system 7 includes an opening / closing valve 71, a flow rate regulator 72, and a pipe 73 provided so as to protrude into the chamber 2, and allows an inert gas supplied from a gas supply source (not shown) to flow into the chamber 2.
The on-off valve 71 supplies or blocks the inert gas flowing into the chamber 2 through the pipe 73 by manually closing and opening the valve.
The flow rate regulator 72 controls the flow rate of the inert gas and adjusts the gas flow rate to the downstream on-off valve 71 and the pipe 73.
The inert gas is made of, for example, nitrogen gas or rare gas.

The conductance valve 8 adjusts the pressure in the chamber 2 by manually controlling the valve opening degree when the pump 6 is driven to depressurize the chamber 2. Further, it functions as a pressure adjusting mechanism for the entire gas in the chamber 2 including the inert gas introduced into the chamber 2 by the gas introduction system 7.
In this example, the example in which the conductance valve 8 is manually controlled to adjust the pressure in the chamber 2 has been described. However, a Pirani gauge (not shown) is installed in the chamber 2 to monitor the pressure, and the conductance valve 8 is monitored. It is good also as a structure which controls pressure automatically and adjusts pressure.

The probe card 10 acquires the electrical characteristic data of the semiconductor element 15 by contacting the probe element 10 a with the semiconductor element 15 of the object to be measured placed on the sample stage 3, and sends it to the measuring instrument 11. Send it out. In the example shown in FIG. 1, the probe card 10 is installed substantially above the semiconductor element 15 placed on the sample stage 3.
The probe portion 10a is a contact portion that protrudes from the probe card 10 and touches the semiconductor element 15, and acquires electrical characteristic data of the semiconductor element 15 from the terminal. The electrical characteristic data is sent to the measuring instrument 11 through the wiring 12a.
Further, the sample stage 3 is connected to the measuring instrument 11 by a wiring 12b.

The reduced-pressure heating measurement apparatus 1 according to the present embodiment has the following operation due to the above-described configuration.
As shown in FIG. 1 and FIG. 2, the semiconductor element 15 to be measured is placed and fixed at a predetermined position on the upper surface 31 of the sample stage 3 by using a presser fitting 32.
After the semiconductor element 15 is arranged, the pump 6 is operated and the conductance valve 8 is opened to depressurize the chamber 2, and the open / close valve 72 of the gas introduction system 7 is opened to deactivate the inert gas. Is introduced into the chamber 2 from the pipe 73, and the inside of the chamber 2 is brought into an inert gas atmosphere.
By energizing the heater 51, the susceptor 44 is irradiated with infrared rays through the thermoelectron shield 53. The susceptor 44 is heated to a maximum of 800 ° C. in a reduced pressure inert gas atmosphere by absorbing infrared rays, and the sample stage 3 and the semiconductor element 15 disposed on the sample stage 3 are heated via the upper insulating member 45. It will be in the state.

As shown in FIG. 1, a wiring 11 b connected to the measuring instrument 11 is connected to the sample stage 3, and a wiring 11 a is connected to the probe card 10. When the probe unit 10 a of the probe card 10 touches the semiconductor element 15, the current flowing through the semiconductor element 15 via the sample stage 3 and the probe card 10 is measured by the measuring instrument 10.
At this time, infrared rays emitted from the heater 51 are irradiated to the susceptor 44 in a state where the thermal electrons are blocked by passing through the thermal electron shield 53. The susceptor 44 heated by infrared irradiation and the sample stage 3 are electrically insulated by the upper insulating member 45, and the peripheral portion of the susceptor 44 is electrically insulated by the lower insulating member 43. .
As a result, in the reduced pressure heating measuring apparatus 1 of the present embodiment, the sample stage 3 and the semiconductor element 15 are less affected by electrical noise and leakage current from the heater 51 as a heat source, and the semiconductor element 15 is interposed via the sample stage 3. An extremely high precision measurement is possible with the order of measurement accuracy when the value of the current flowing through is measured is 1 nA (1 × 10 −9 A) or less.

In the reduced pressure heating measuring apparatus 1 of the present embodiment, by using the chamber 2 in a reduced pressure state in which a vacuum or an inert gas is flowed, it is possible to heat only the semiconductor element 15 and its surroundings to a high temperature. Therefore, it is possible to shorten the temperature rise and temperature drop time. Further, in the reduced pressure heating measuring apparatus 1, the heating unit 4 and the sample stage 3 are electrically insulated using an insulating member having excellent thermal conductivity and mechanical accuracy, so that low electrical noise and low noise can be obtained. It has leakage current characteristics.
Thereby, in a state where the semiconductor element 15 arranged on the sample stage 3 is heated in a range of 100 ° C. to 600 ° C., the reliability evaluation of the insulating film formed on the semiconductor substrate 15 and the electrolysis such as the copper wiring are performed. Can be used to evaluate migration.

As described above, according to the reduced pressure heating measurement apparatus 1 of the present embodiment, the chamber 2 in which the semiconductor element 15 can be arranged at a predetermined position and the semiconductor element 15 can be arranged in advance at a predetermined position. The sample stage 3, the heating mechanism 5 capable of adjusting the semiconductor element 15 arranged at a predetermined position on the sample stage 3 to a predetermined temperature, the pump 6 capable of reducing the pressure in the chamber 2, and the chamber 2 is provided with a gas introduction system 7 for introducing an inert gas into the chamber 2 and a conductance valve 8 which is a pressure adjusting mechanism for the gas containing the inert gas in the chamber 2. When the sample stage 3 and the semiconductor element 15 are heated under a reduced pressure filled with water and the current value A flowing through the semiconductor element 15 through the sample stage 3 is measured, As the accuracy of the order is 1nA (1 × 10-9A) below, and a reduced construction electrical noise and leakage current.
Accordingly, it is possible to realize a reduced pressure heating measuring apparatus for semiconductor elements with a short temperature rising and cooling time and high measurement accuracy.
Further, according to the reduced pressure heating measuring apparatus 1 of the present embodiment, the heating unit 4 and the sample stage 3 are separated from each other, whereby the sample stage 3 of mechanical deformation and electrical noise generated by heating of the heater 51 is obtained. The impact on the is suppressed.
Therefore, it is possible to realize a reduced pressure heating measuring apparatus for semiconductor elements with high measurement accuracy with a simple configuration.

  Note that if a ground line (not shown) is connected to the susceptor 44, the thermoelectron induced current emitted from the heater 51 can be further reduced, so that low noise measurement at high temperatures is possible.

Examples of the reduced-pressure heating measuring apparatus for semiconductor elements according to the present invention will be described below.
As shown in FIG. 1 and FIG. 2, a reduced pressure heating measuring apparatus for semiconductor elements according to the present invention was produced, and an evaluation test shown in the following items was performed.
In each example, the thermoelectron shield 53 was tested using a molybdenum material as the material, with a mesh size of 2 mm and a thickness of 0.6 mm.
Molybdenum used as the material of the thermionic shield 53 has an electric resistivity of 5.2 × 10 ⁻⁶ Ωcm, which is the smallest among the rare earth metals, and has high conductivity even when oxidized. (MoO ₂ electrical resistivity: 8.8 × 10 ⁻⁵ Ωcm) and the like have been clearly shown in the literature (“Numerical Ref. Revised 4th Edition, Chemical Handbook, Basic II "The Chemical Society of Japan").

[Semiconductor element surface temperature and susceptor temperature]
The semiconductor element 15 was placed and fixed on the sample stage 3, the element surface temperature of the semiconductor element 15 and the temperature of the susceptor 44 were measured, and the average and variation of the element surface temperatures were examined.
Thermocouples were attached to a total of five locations, one at the center of the surface of the semiconductor element 15 and four at the top, bottom, left, and right at a distance of 3.3 cm from this center, and each temperature was measured to obtain an average temperature.
Further, the variation temperature (T _error ) was determined from the measured values of the temperatures at the five positions described above using Equation 1. Here, T _max is the maximum temperature at five measurement points, and T _min is the minimum temperature.

In addition, the pressure in the chamber 2 at the time of measurement was 1 Pa or less.
The results are shown in the graph of FIG.

As shown in FIG. 3, it has been clarified that the surface temperature of the semiconductor element 15 increases linearly as the temperature of the susceptor 44 increases.
It has been found that when the susceptor 44 is heated to 600 ° C., the average surface temperature of the semiconductor element 15 reaches 300 ° C.
Further, it has been clarified that the variation increases as the surface temperature of the semiconductor element 15 increases, but the range of the variation is about ± 0.5% with respect to the average temperature, which is a very good surface. It shows the in-plane uniformity of temperature.

[Noise current and susceptor temperature]
The semiconductor element 15 was placed and fixed on the sample stage 3, and the noise current flowing from the heater 51 through the susceptor 44 to the sample stage 3 and the temperature of the susceptor 44 were measured.
As shown in FIG. 4, when the temperature of the susceptor 44 is in the range of room temperature to 500 ° C., the noise current flowing through the sample stage 3 is substantially constant at about 2 pA, and has a very stable characteristic that does not depend on the temperature of the susceptor 44. Show.
On the other hand, when the temperature of the susceptor 44 is 600 ° C. (the temperature of the surface of the semiconductor element 15 is about 300 ° C.), the noise current is reduced to 0.5 pA. This is due to the current caused by the thermoelectrons emitted from the heater 51, but since the magnitude of the noise current itself is very small, it has become clear that low noise measurement on the order of pA is possible. .

[Semiconductor element surface temperature and chamber pressure]
The semiconductor element 15 was placed and fixed on the sample stage 3, and the element surface temperature of the semiconductor element 15 and the pressure in the chamber 2 were measured to examine the average of the element surface temperature and the variation in the chamber pressure. The test was performed under conditions where the temperature of the susceptor 44 was 600 ° C.
As shown in FIG. 5, it is clear that the surface temperature of the semiconductor element 15 increases as the pressure in the chamber 2 increases, and the surface temperature of the semiconductor element 15 reaches 350 ° C. or higher when the pressure in the chamber 2 is 100 Pa. is there. Further, as in the susceptor temperature dependency result shown in FIG. 3, the variation in the surface temperature of the semiconductor element 15 increases as the pressure in the chamber 2 increases, but the range of the variation is ± 0.5 with respect to the average temperature. %, It indicates in-plane uniformity with a very good surface temperature.

[Noise current and pressure in the chamber]
The semiconductor element 15 was placed and fixed on the sample stage 3, and the noise current flowing from the heater 51 through the susceptor 44 to the sample stage 3 and the pressure in the chamber 2 were measured. The test was performed under conditions where the temperature of the susceptor 44 was 600 ° C.
As shown in FIG. 6, it is clear that the noise current flowing through the sample stage 3 increases as the pressure in the chamber 2 increases. However, even when the pressure in the chamber 2 is 100 Pa, that is, the surface temperature of the semiconductor element 15 is heated to 350 ° C. or higher (see FIG. 5), the noise current is as small as a few tens pA.
From the above results, by using the reduced pressure heating measuring apparatus according to the present invention, it is possible to measure a low noise on the order of 1 nA (1 × 10 ⁻⁹ A) or less of a semiconductor element heated to a high temperature of 350 ° C. It became clear that

As described above, according to the reduced-pressure heating measuring apparatus of the present invention, the sample stage of mechanical deformation and electrical noise generated by the heating of the heater 51 is obtained by making the heating unit 4 and the sample stage 3 separated. 3 can be suppressed. Further, the chamber 2 is used in a vacuum or a reduced pressure state in which an inert gas is supplied, and only the semiconductor element 15 and its surroundings are heated to a high temperature, whereby the temperature rise and temperature fall time can be shortened. If a ground line is connected to the susceptor 44, the thermoelectron induced current emitted from the heater 51 can be reduced, and electrical noise at high temperatures can be reduced.
Accordingly, it is possible to realize a reduced pressure heating measuring apparatus for semiconductor elements with a short temperature rising and cooling time and high measurement accuracy.

It is the schematic explaining an example of the pressure-reduction heating measuring apparatus of this invention. It is the schematic which shows the hot chuck | zipper structure of the principal part of the pressure reduction heating measuring apparatus of this invention. It is a graph explaining the temperature characteristic of the pressure-reduction heating measuring apparatus of this invention. It is a graph explaining the susceptor temperature dependence of the noise current of the pressure reduction heating measuring apparatus of this invention. It is a graph explaining the pressure dependence of the susceptor temperature of the pressure reduction heating measuring apparatus of this invention. It is a graph explaining the pressure dependence of the noise current of the pressure reduction heating measuring apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vacuum heating measuring apparatus (vacuum heating measuring apparatus for semiconductor elements), 2 ... Chamber, 3 ... Sample stage, 4 ... Heating unit, 43 ... Lower insulating member, 43a ... Transmission hole, 44 ... Susceptor, 44a ... Temperature sensor, 45 ... Upper insulating member, 5 ... Heating mechanism, 51 ... Heater, 53 ... Thermionic shield, 6 ... Pump (evacuation system), 7 ... Gas introduction system, 8 ... Conductance valve (pressure adjustment mechanism), 9 ... Transfer stage 10 ... probe card, 15 ... semiconductor element

Claims (15)

A chamber in which a semiconductor element can be arranged at a predetermined position, a sample stage in which the semiconductor element can be arranged in a predetermined position in advance, and the semiconductor element arranged in a predetermined position on the sample stage are determined in advance. A heating mechanism that can be adjusted to a predetermined temperature, a vacuum exhaust system that can reduce the pressure in the chamber, a gas introduction system that introduces an inert gas into the chamber, and a gas that contains the inert gas in the chamber And a pressure adjusting mechanism of
Order of measurement accuracy when the sample stage and the semiconductor element are heated while the chamber is under vacuum or under reduced pressure filled with an inert gas, and the current value flowing in the semiconductor element through the sample stage is measured. Is 1 nA (1 × 10 ⁻⁹ A) or less.   2. The semiconductor element according to claim 1, wherein the semiconductor element comprises a single-layer film made of an insulating film or a metal film, or a semiconductor element having a composite film composed of at least two of these. Vacuum heating measuring device. The heating mechanism is composed of a heater made of one or more materials of an alloy made of chromium, aluminum and iron, platinum, nichrome, tungsten, and is housed in a heating unit.
3. The reduced pressure heating measurement apparatus for a semiconductor element according to claim 1, wherein the heating unit is arranged to be electrically insulated from the sample stage. 4.   The thermoelectron shield part which shields the thermoelectron which generate | occur | produces from the said heating mechanism is provided, This thermoelectron shield part is earth | grounded in the one place of the said chamber, The any one of Claims 1-3 characterized by the above-mentioned. The vacuum heating measuring apparatus for semiconductor elements as described.   The said thermoelectron shield part consists of carbon or a metal net | network, The vacuum heating measuring apparatus for semiconductor elements of Claim 4 characterized by the above-mentioned.   The vacuum heating measurement apparatus for a semiconductor element according to any one of claims 1 to 5, wherein a lower insulating member for electrical insulation is provided between the heating mechanism and the sample stage.   The said lower insulation member consists of quartz or a ceramic, The vacuum heating measuring apparatus for semiconductor elements of Claim 6 characterized by the above-mentioned. The lower insulating member is provided with a transmission hole, a susceptor is attached to the transmission hole, and the susceptor is heated by infrared radiation of the heating mechanism,
8. The semiconductor device reduced pressure heating measurement apparatus according to claim 7, wherein a temperature sensor is provided at any location of the susceptor.   The reduced pressure heating measuring apparatus for a semiconductor element according to claim 8, wherein the susceptor is made of carbon.   10. The reduced pressure heating measurement for a semiconductor element according to claim 8, wherein an electrically insulating upper insulating member is disposed above the susceptor, and the sample stage is disposed above the upper insulating member. apparatus.   The said upper insulating member consists of at least 1 or more materials among an alumina, a sapphire, and quartz, The vacuum heating measuring apparatus for semiconductor elements of Claim 10 characterized by the above-mentioned.   The reduced pressure heating measurement apparatus for a semiconductor element according to any one of claims 1 to 11, wherein the sample stage is made of at least one material selected from molybdenum, nickel, tantalum, and tungsten.   The vacuum heating measurement apparatus for a semiconductor element according to any one of claims 1 to 12, wherein the sample stage forms a measurement electrode of the semiconductor element when the semiconductor element is arranged.   14. The semiconductor device according to claim 3, wherein the heating unit and the sample stage are installed on a transfer stage that can be driven by an X axis, a Y axis, and a θ axis. Vacuum heating measuring device. The reduced pressure heating measurement for a semiconductor device according to any one of claims 1 to 14, wherein a probe card or a micro prober for contacting the semiconductor device from above the sample stage is provided in the vicinity of the sample stage. apparatus.

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