KR20050048842A - Apparatus and method for analyzing surface of semiconductor - Google Patents

Abstract

The present invention relates to a semiconductor surface analysis apparatus and method for determining whether a semiconductor unit process is normal, and to reduce an analysis process time and a semiconductor manufacturing process time by simultaneously cleaning a plurality of semiconductor samples. The present invention is installed inside the main chamber and the main chamber to generate a mixed gas into the plasma by RF energy, and using the plasma to clean the plurality of semiconductor sample surfaces at the same time and the cleaning unit is installed inside and outside the main chamber Characterized in that the analysis unit for analyzing the surface of the plurality of semiconductor samples washed in. In other words, before the step of analyzing the surface constituents and the chemical bonding state of the semiconductor sample to determine whether the semiconductor unit process is normal, it characterized in that the surface of the plurality of contaminated semiconductor sample is washed simultaneously.

Therefore, according to the present invention, the time required for the analysis process and the semiconductor manufacturing process time can be shortened.

Description

Apparatus and method for analyzing surface of semiconductor

The present invention relates to a semiconductor surface analysis apparatus and method, and more particularly to an improved surface analysis apparatus and method for analyzing the surface of the semiconductor sample by washing a plurality of semiconductor samples at the same time.

Generally, in the semiconductor device manufacturing process, a plurality of unit processes are continuously performed. That is, the wafer is manufactured into a chip, which is a semiconductor device, by repeatedly performing processes such as a photo process, a diffusion process, an etching process, and a deposition process.

In addition, an analysis process is performed between the unit processes, and the process determines whether the unit process is normal.

The semiconductor surface analysis apparatus performing the analytical process is a device for observing surface components and chemical bonding states of several tens of micrometers to hundreds of micrometers in depth, including AES (auger electron spectroscopy), XPS (x-ray photoelectron spectroscopy), and SIMS ion mass spectrometry). When AES enters a semiconductor sample (hereinafter referred to as a 'sample'), the AES can determine the surface composition of the sample using auger electrons emitted by the sample's interaction with the electron beam. In addition, the area resolution is less than 1㎛², it is a device that can find the components of the micro-region. XPS is a device that can determine the composition by measuring the kinetic energy of photoelectron emitted from the sample by X-ray. Lastly, SIMS has a small amount of component analysis and has the advantage of finding out all the elements, but sputtering is not suitable for the component analysis of the micro domain.

In general, the surface analysis apparatus includes a main chamber, an analyzer connected to the main chamber to perform surface analysis of a sample, a holder for fixing the sample, an irradiation unit for irradiating an X-ray or an electron beam to the sample; And an etching gun for injecting a gas (eg, argon, etc.) having a purpose of cleaning the contaminants present on the surface of the sample before performing the analysis of the sample. The argon gas incident on the surface of the sample was ionized by positively charged argon ions and used to clean the surface of the sample or to etch for analysis of surface components and chemical bonding states of several hundreds of microns deep. .

A surface analysis process is performed in the main chamber, and a holder formed in the main chamber is mounted with a sample formed by cutting a wafer that has undergone a preceding process (eg, a deposition process). Here, the sample is transferred to the surface analysis apparatus in the state exposed to the air, the surface of the sample is likely to be contaminated by carbon or oxygen (Oxygen). Therefore, cleaning of the surface of the sample is required before performing surface analysis of the sample.

However, the cleaning of the sample surface should be performed intensively for each sample by using an etching gun. The surface analysis of the sample is performed after individually washing a plurality of samples mounted on the holder.

In the case where a plurality of samples spaced apart at a narrow interval from the holder are individually washed by using an etching gun, that is, when one sample is washed and then another sample is washed, the particles that are already washed are later washed. Can be contaminated again.

Therefore, the conventional surface analysis apparatus cleans any one of a plurality of samples mounted on the holder by using the etching gun, and then analyzes the sample by using an analyzer. Subsequently, another sample is washed and then analyzed.

According to the above-described prior art, in order to analyze the surface of a sample, any one of a plurality of samples is individually washed to proceed with the analysis process, and another sample is washed and then proceeded with the analysis process.

Due to such individual washing and analysis, there is a problem of increasing an analysis process time and thereby increasing a semiconductor manufacturing process time.

 In addition, when the sample is washed using argon gas, there is a problem that a so-called pre-ferential etching (hereinafter, referred to as 'PE') in which a small mass of elements are etched first occurs.

Accordingly, an object of the present invention is to solve the conventional problems as described above. First, a method for shortening an analysis process time and a semiconductor manufacturing process time by simultaneously washing a plurality of samples mounted on a holder of a surface analysis device; It is to provide a semiconductor surface analysis apparatus that can provide this.

Second is to provide a method for minimizing or preventing generation of 'PE' by washing the sample in a plasma state instead of the conventional argon gas, and a semiconductor surface analysis apparatus capable of providing the same.

In order to achieve the above object, the surface analysis apparatus of the semiconductor sample of the present invention is installed in the main chamber and the main chamber to generate a mixed gas into plasma by RF energy and simultaneously wash the surface of a plurality of semiconductor samples using the plasma. And a cleaning unit installed inside and outside the main chamber to analyze a plurality of semiconductor sample surfaces washed by the cleaning unit. In other words, before the step of analyzing the surface constituents and the chemical bonding state of the semiconductor sample to determine whether the semiconductor unit process is normal, it characterized in that the surface of the plurality of contaminated semiconductor sample is washed simultaneously.

Here, the cleaning unit includes a quartz tube, an RF coil surrounding the quartz tube, an RF power source connected to the RF coil to apply RF energy, and a nozzle for injecting a mixed gas into the quartz tube.

In addition, the analyzer is installed in the main chamber to emit an electromagnetic wave from the surface of the sample by the irradiation unit for irradiating the electromagnetic wave to the surface of the semiconductor sample and the electromagnetic wave irradiated from the irradiation unit and an analyzer for analyzing the surface of the semiconductor sample by using the electron It is composed.

As described above, according to the present invention, it is possible to shorten the time required for the analysis process and the semiconductor manufacturing process time by simultaneously cleaning a plurality of samples using plasma.

Such a characteristic configuration and the effects of the present invention will be more clearly understood through the detailed description of the embodiments with reference to the accompanying drawings.

Embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. In addition, the shape of the elements in the drawings and the like are shown in order to emphasize a more clear description, elements denoted by the same reference numerals in the drawings means the same element.

The semiconductor surface analysis apparatus for performing the analysis process includes AES (auger electron spectroscopy), XPS (x-ray photoelectron spectroscopy), SIMS (secondary ion mass spectrometry), etc. Hereinafter, the present invention is XPS (x-ray photoelectron spectroscopy) Is explained by. However, it will be apparent to those skilled in the art that the present invention can be replaced by a device other than the XPS.

1 is a plan view of a surface analysis apparatus according to an embodiment of the present invention, Figure 2 is a front view of Figure 1 in particular showing the main chamber. 3 is a view showing in detail the quartz tube in the cleaning unit.

First, referring to Figures 1, 2 and 3 look at the configuration of the surface analysis apparatus according to an embodiment of the present invention.

The surface analyzing apparatus is mainly composed of a main chamber 11, an analysis unit 30, a cleaning unit 40, a sub chamber 18, and the like.

The main chamber 11 and the subchamber 18 are connected to both ends of the connection passage 9 having the inner door 7, and the analysis unit 30 and the cleaning unit 40 are connected to the main chamber 11. It is installed inside and outside.

A connecting passage 9 is integrally formed in the main chamber 11 so that the subchamber 18 and a sample can be transferred to each other, and an inner door 7 is installed in the connecting passage 9. When the inner door 7 transfers the sample 1 from the subchamber 18 to the main chamber 11 or from the main chamber 11 to the subchamber 18, the inner chamber 11 and the subchamber The opening and closing operation is performed under the same conditions as in (18). The same condition refers to a state in which both chambers have the same vacuum pressure. The main chamber 11 maintains a vacuum state, and the cleaning and surface analysis of the sample 1 is performed therein, and includes a cleaning unit 40 using plasma and an analysis unit 30 for surface analysis. Doing. It is also provided with a transfer stage (15) and a holder (5) provided on the transfer stage (15) to mount a plurality of samples (1).

The cleaning unit 40 is composed of a quartz tube 16, an RF coil surrounding the RF coil 17, a RF power source 22, and a nozzle 21. The sample 1 Before analyzing the surface of), it has a function to clean the surface contaminated by carbon or oxygen.

The nozzle 21 is installed on one surface of the main chamber 11 adjacent to the connecting passage 9 to supply the mixed gas to the quartz tube 16. The mixed gas may consist of argon and oxygen.

The RF coil 17 surrounds the quartz tube 16 installed in the main chamber 11. When the mixed gas is injected into the quartz tube 16 through the nozzle 21, RF energy is supplied from the RF power source 22. Is approved. At this time, the plasma is generated, the plasma particles are to wash a plurality of samples (1) mounted on the holder (5) at the same time. Here, the plasma refers to a state in which gas molecules coexist as various kinds of highly reactive materials ranging from a ground state or an excited state to electrons, ions, and molecules. The RF power supply 22 is connected to the outside of the main chamber 11.

The analyzer 30 includes an analyzer 12, an irradiator 13 for irradiating X-rays to the surface of the sample, and an etching gun 14 for injecting argon ions into the surface of the sample 1. The cleaning unit 40 has a function of analyzing the surface of the sample (1) washed.

A part of the analyzer 12 is installed inside the main chamber 11, and the other part is connected to the outside of the main chamber 11 to perform a function of analyzing the surface of the sample 1. The operating principle of the analyzer 12 is a well-known technique, and a detailed description thereof will be omitted.

The irradiator 13 is installed in the main chamber 11 so that X-rays generated by a light source (not shown) are incident on the surface of the sample 1, and the sample 1 exposed to the X-rays is photoelectron. ) Will be emitted. In this case, the analyzer 12 can determine the surface composition of the sample 1 by measuring the kinetic energy of the photoelectrons.

The etching gun 14 is installed in the main chamber 11 to inject an etching gas, for example argon gas, into the surface of the sample 1. Argon gas is ionized and incident with positively charged argon ions. Conventional surface analyzers have used etching guns for the purpose of cleaning the surface of a sample or observing a surface of a depth of several hundred micrometers, ie, deep constituents and chemical bonding. On the other hand, the etching gun 14 of the surface analysis apparatus according to the present invention is mainly used only for the observation of the constituents and the chemical bonding state of the surface, that is, the depth of several hundreds of microns. On the other hand, the cleaning of the surface of the sample 1 is performed by the plasma in the cleaning unit 40.

The transfer stage 15 penetrates through one side of the main chamber 11 to support the holder 5. The transfer stage 15 transfers the holder 5 from the cleaning unit 40 to the analysis unit 30 or from the analysis unit 30 to the cleaning unit 40. At this time, the holder 5 is installed on the transfer stage 15 and is equipped with a plurality of samples (1). Since the holder 5 is also a well known technique, a detailed description thereof will be omitted.

A connection passage 9 is integrally formed at one side of the subchamber 18 and coupled to the main chamber 11 with the connection passage 9 interposed therebetween. The subchamber 18 includes a transfer robot 19 capable of transferring the sample 1 to the main chamber 11 or transferring the sample in the main chamber 11 to the subchamber 18.

Next, a detailed operation of the surface analyzer having the above configuration will be described.

An analysis process is performed between the unit processes to determine whether each of the unit processes, such as a photo process, a diffusion process, an etching process, and a deposition process, is normal. A sample formed by cutting a wafer after each process is finished (1) Is transferred to the subchamber 18. Subsequently, when the environment of the main chamber 11 and the subchamber 18 become the same condition, that is, when the vacuum pressure of both chambers is the same, the connecting passage 9 of the main chamber 11 and the subchamber 18 is provided. The inner door 7 installed therein is opened. At this time, the transfer robot 19 in the subchamber 18 transfers the sample 1 to the holder 5 of the main chamber 11. The holder 5 is positioned in the quartz tube 16 of the cleaning unit 40, and the mixed gas is injected into the quartz tube 16 of the cleaning unit 40 through the nozzle 21. In this case, plasma is generated by applying RF energy from the RF power source to the quartz tube 16, and the plasma particles simultaneously wash a plurality of samples 1 mounted on the holder 5.

Then, the holder 5 equipped with a plurality of samples 1 is transferred to the analyzer 12 by the transfer stage 15 for surface analysis of the samples. At this time, the irradiator 13 irradiates the sample with X-rays and the sample 1 exposed to the X-rays emits photoelectrons. By measuring the kinetic energy of the photoelectrons, the analyzer 12 can determine the surface components of the sample 1.

On the other hand, the analyzer 12 is easy to observe the surface constituents and chemical bonding state of the tens of Å depth, but it is not easy to observe the constituents and chemical bonding state of the surface of the hundreds of Å depth. However, by injecting argon ions through the etching gun 14 to etch the surface of the sample 1, it is easy to observe the constituent material and the chemical bonding state of the surface of several hundreds of micrometers deep, that is, deep.

The sample 1 having the above-described analysis process is transferred from the main chamber 11 to the subchamber 18 and out of the subchamber 18 by the transfer robot 19 of the subchamber 18.

As described above, according to the exemplary embodiment of the present invention, unlike the conventional surface analysis apparatus, a plurality of samples contaminated by carbon or oxygen are simultaneously washed using plasma to analyze an analysis process time and a semiconductor manufacturing process. There is a characteristic that can shorten the time.

On the other hand, the present invention is not limited to the above-described embodiments, it is apparent that modifications and improvements can be made by those skilled in the art without departing from the spirit of the present invention. For example, it is obvious to those skilled in the art that the analyzer may not only analyze a plurality of washed samples individually, but may also be designed to analyze them simultaneously.

As described above, according to the present invention, the plasma is washed simultaneously with a plurality of samples, thereby reducing the time required for the analysis process and the semiconductor manufacturing process time.

In addition, since the sample is washed in a plasma state, there is an effect of minimizing or preventing so-called 'PE' (Preferential Etching) in which a small mass of elements is etched first.

1 is a plan view of a surface analysis apparatus according to an embodiment of the present invention.

FIG. 2 is a front view of FIG. 1 showing in particular the main chamber.

3 is a view showing in detail the quartz tube in the cleaning unit.

<Description of reference numerals for main parts of the drawings>

            11: main chamber 12: analyzer

            13: irradiation part 14: etching gun

            16: quartz tube 17: RF coil

            21: nozzle 22: RF power

            30: analysis unit 40: cleaning unit

Claims (8)

In the surface analysis device for analyzing the surface of the semiconductor sample to determine whether the semiconductor unit process is normal, Main chamber; A cleaning unit installed inside the main chamber to generate a mixed gas into plasma by RF energy and to simultaneously wash a plurality of semiconductor sample surfaces by using the plasma; And Surface analysis apparatus characterized in that provided in the interior and exterior of the main chamber to analyze the plurality of semiconductor sample surfaces washed by the cleaning unit. The method of claim 1, wherein the cleaning unit Quartz tube; An RF coil wrapped around the quartz tube; An RF power supply connected to the RF coil to apply RF energy; And Surface analysis apparatus comprising a nozzle for entering the mixed gas into the quartz tube. The method of claim 1, wherein the analysis unit An irradiation unit installed in the main chamber to irradiate the surface of the semiconductor sample with electromagnetic waves; And an analyzer for emitting electrons from the surface of the sample by the electromagnetic waves irradiated by the irradiator and analyzing the surface of the semiconductor sample using the electrons. The method of claim 2, The mixed gas is a surface analysis device, characterized in that mixed with argon gas and oxygen. The method of claim 3, wherein And an etching gun provided in the main chamber to inject etching gas into the surface of the sample for etching the surface of the sample for in-depth analysis of the semiconductor sample. The method according to claim 3 or 5, Electromagnetic wave irradiated from the irradiation unit is X-rays or electron beam surface analysis device. The method of claim 5, The etching gas incident on the surface of the semiconductor sample in the etching gun is ionized into argon ions having a positive charge as argon gas, and is incident. In the method of analyzing the surface of a semiconductor sample using a surface analysis device having a cleaning unit and an analysis unit, Injecting a semiconductor sample having a unit process completed into the cleaning unit; Generating plasma from the quartz tube of the cleaning unit and simultaneously cleaning surfaces of a plurality of contaminated semiconductor samples; And analyzing the surface constituents and the chemical bonding state of the washed semiconductor sample to determine whether the semiconductor unit process is normal.