JPH02205682A - Charged particle beam type processing device - Google Patents

Abstract

PURPOSE:To efficiently execute charged particles beam processing by using laser light and sensor to detect the deviation between an irradiation position of the charge beam and a gas blowing position and changing the direction of a gas nozzle according to the deviation quantity thereof. CONSTITUTION:A gas for processing is blown from the gas nozzle 11 consisting of a body 11b having an injection part 11a and an introducing pipe 11c to the work, such as semiconductor wafer 1, imposed on a sample base 2 set to a positioning device (not shown), such as X-Y table, and the work is irradiated with the charge beam, such as electron beam 5, by which the work is subjected to processing, such as etching. The work is irradiated with the laser light 13 coaxial with the gas nozzle 11 by a laser light projecting device having a lens 12, etc., of the above-mentioned charged particle beam type processing device. This laser light 13 is detected by a two-dimensional detector 14, such as CCD. The above-mentioned electron beam 5 is then detected. The deviation in the blowing position of the gas 7 with respect to the irradiation position of the electron beam 5 is detected in this way. The direction of the nozzle 11 is changed according to this deviation quantity to determine the gas blowing position at the position to be irradiated with the electron beam.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used when modifying or changing patterns such as wiring of an LSI or a photomask for an LSI using an electron beam or an ion beam. This invention relates to a charged beam processing device.

[Conventional technology]

Conventionally, in order to modify or change patterns such as wiring of LSIs and LSI photomasks with high precision, a method was used in which a focused electron beam or ion beam was irradiated onto the sample while blowing gas. Charged beam processing equipment is used. This method, for example, Y, 0ch
iai et al.”Maskless etching of
GaAs and InP using a scan
ning microplasma, J, Vac,
Sci, Technol, B+νO1,1,N004I
P.

1047-1049. S, Matsui (th “Ne
w 5elective deposition
chnology by electron beaa
+ 1 unduced 5 surface reactio
n'', Jpn, J, Appl, Phys, Vol.
, 23. No, 9. P.

L706-L70B, and 5aitoh et al.
tactical results of pho
Lomask repair using for
cused ion beats technolo
gy”, J, Vac, Sci, Technol, B+V
o1.6. No.

3, P, 1032-1034. This method will be explained using FIGS. 4 and 5.

Fig. 4 is a cross-sectional view showing a schematic configuration of a charged beam processing device used to carry out this type of conventional method, and Fig. 5 is a cross-sectional view for explaining the processing state. 2 shows the case where the processing gas is supplied to the front side of the irradiation position of the charged beam, and (b) also shows the case where the processing gas is supplied to the back side of the irradiation position of the charged beam,
Figure (c) shows a state in which the processing gas is supplied to an appropriate position.

In these figures, ■ is a semiconductor wafer (hereinafter simply referred to as a wafer), 2 is a sample stand for holding this wafer l, and this sample stand 2 is used for positioning, for example, an X-Y table in the sample chamber 3. It is attached via the device 2a,
It is provided horizontally movably by this positioning device 2a. A vacuum pump (not shown) is connected to the sample chamber 3, and the inside of the sample chamber 3 is sealed, and the vacuum pump pumps 10-' to 10-' Torr into the sample chamber 3.
It is constructed so that a high vacuum state of about r can be obtained.

Reference numeral 4 denotes an electron beam column that generates an electron beam 5. This electron beam column 4 is configured to generate an electron beam 5 narrowly focused to about 0.1 μm. It is arranged above the sample stage 3. Further, this electron beam column 4 is provided with a deflection device (not shown) for electrically deflecting the irradiation direction of the electron beam 5, and this deflection device directs the electron beam 5 to any desired position on the sample. The site can be irradiated with high precision.

Reference numeral 6 denotes a gas nozzle for supplying a processing gas 7 onto the wafer 1, and this gas nozzle 6 is fixed to the sample chamber 3 with its injection port 6a facing into the sample chamber 3.

Next, the operation of the conventional charged beam processing apparatus configured as described above will be explained. −For example, deposition (
Forming an AI wiring pattern on the wafer 1. ) will be explained below. First, the wafer 1 is mounted on the sample stage 2, and the inside of the sample chamber 3 is brought into a vacuum state at a predetermined pressure. Next, trimethylaluminum (AI(CHa)i) gas is blown onto the wafer 1 from the gas nozzle 6 as a processing gas 7. At the same time as this gas is blown, the electron beam column 4 is operated to selectively irradiate the wafer 1 with an electron beam 5 having an energy of 30 eV.

At this time, positioning between the processed part of the wafer 1 and the irradiation position of the electron beam 5 is performed by horizontally moving the sample stage 3, and fine adjustments are made by deflecting the electron beam 5 with the deflection device of the electron beam column 4. carried out by When the wafer 1 is irradiated with the electron beam 5 while spraying trimethylaluminum gas, the molecules of the trimethylaluminum gas adsorbed on the surface of the wafer 1 are decomposed by the irradiation with the electron beam 5, and A1 is deposited on the surface of the wafer 1. will be formed. Deposition can be performed in this manner. In addition, in this charged beam processing apparatus, deposition can be performed as described above even if a focused ion beam is used instead of the electron beam 5, and etching gas is used instead of trimethylaluminum gas as the processing gas 7. Etching can also be performed using chlorine (C1□) gas.

Therefore, by using the conventional charged beam processing apparatus configured as described above, it is possible to perform so-called maskless processing without going through a photolithography process.
Furthermore, since the processing accuracy is high, the circuit pattern can be easily corrected or changed.

[Problems to be Solved by the Invention] However, in the conventional charged beam processing apparatus configured as described above, since the gas nozzle 6 is fixed to the EH chamber 3, The position at which the processing gas 7 is blown changes, and it is difficult to accurately determine the position at which the processing gas 7 is blown and the position at which the electron beam 5 is irradiated. For this reason, as shown in FIG. 5(a), the processing gas 7 is blown onto the front side of the area to be irradiated with the electron beam 5, or as shown in FIG. 5(b), the electron beam 5 is If the electron beam 5 is blown toward the back of the region to be irradiated, the amount of processing gas 7 supplied at the irradiation position of the electron beam 5 will be reduced, and the processing speed will be reduced. Furthermore, when the gas nozzle 6 is replaced, the orientation of the gas nozzle 6 is also changed, which causes a problem in that the processing conditions change.

[Means to solve the problem]

The charged beam processing apparatus according to the present invention includes a laser beam irradiation device in which the direction of irradiation of the laser beam is changed according to the direction of a gas supply nozzle, and a position of the irradiation of the charged beam depending on the position where the laser beam is incident. The gas spraying apparatus is equipped with a sensor that detects a positional deviation, and a positioning means that changes the direction of the nozzle according to the amount of deviation, and positions the gas spraying position at the charged beam irradiation position.

[For production]

The direction of the gas supply nozzle can be detected by the position of the laser beam incident on the sensor, and the positioning means directs the gas supply nozzle to the charged beam irradiation position, so the spraying of the processing gas is The position and the irradiation position of the charged beam can be accurately determined.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

FIG. 1 is an enlarged perspective view of a main part of a charged beam processing apparatus according to the present invention, and FIG. 2 is a perspective view of a sample stage used in the charged beam processing apparatus according to the present invention. In these figures, the same or equivalent members as those explained in FIGS. 4 and 5 are designated by the same reference numerals, and detailed explanation thereof will be omitted. In these figures, 11
1 is a gas nozzle for injecting processing gas 7, and this gas nozzle 11 is formed into a substantially cylindrical shape and has a gas injection port 1 at the tip.
1a, and a gas introduction pipe 11c that is integrally provided with the nozzle body 11b and connected to a processing gas supply device (not shown), and a sample chamber (not shown). A positioning device (not shown) is used to allow the direction to be changed freely. Also,
A lens 12 for condensing laser light, which will be described later, is attached to the end of the nozzle body 11b opposite to the gas injection port 11a. A laser beam irradiation device (not shown) is connected to this gas nozzle 11, and a laser beam 13 irradiated from this laser beam irradiation device is converged by the lens 12, passes through the gas nozzle body 11b, and exits from the injection port 11a. It is configured to irradiate a CCD, which will be described later. That is, the axis 1 of this laser beam 13
3a coincides with the axis of the gas nozzle 11, and the spraying direction of the processing gas 7 also matches, so by detecting the irradiation position of the laser beam 13, the spraying position of the processing gas 7 can be adjusted. can be detected. 1
4 is a two-dimensional detector for detecting the irradiation position of the laser beam 13, and this two-dimensional detector is formed by an image pickup device such as a COD, and is mounted on the sample stage 2 as shown in FIG. has been done. Note that 14a and 14b are CCD
Shows the top pixel. Further, this two-dimensional detector (hereinafter simply referred to as CCD) 14 is connected to the gas nozzle positioning device via a control device (not shown), and the gas nozzle 11 is adjusted according to the incident position of the laser beam 13. It is configured so that it can be turned.

Next, a procedure for positioning the gas spraying position and the electron beam irradiation position using the charged beam processing apparatus configured as described above will be explained. First, the sample stage 2 is moved to place the CCD 14 at the electron beam irradiation position. Then, the CCD 14 is irradiated with laser light 13 from the injection port 11a via the gas nozzle 11. At this time, since the position of the pixel 14a on the CCD 14 where the laser beam 13 is incident is approximately the same as the position where the processing gas 7 is blown, the CC
By checking the output of each pixel on D14 and detecting the pixel 14a onto which the laser beam 13 is incident, the spraying position of the processing gas 7 can be detected. Next, the CCD 14 is irradiated with the electron beam 5. When the pixel 14b is irradiated with the electron beam 5, charges are generated in the pixel 14b by the electron beam 5, and the output of the pixel 14b becomes high level. That is, by checking the output of each pixel on the CCD 14 and detecting this pixel 14b, the position where the electron beam 5 is incident can be detected. In this way, the incident positions of the laser beam 13 and the electron beam 5 can be detected. And both are CC
If the laser beam 13 is incident on a different position on D14, the control device and positioning device mechanically slightly move the gas nozzle 11 to change its direction, measure the incident position of the laser beam 13 as described above, and adjust the beam. Perform alignment. If similar alignment is performed while electrically deflecting the electron beam 5 after this mechanical alignment, alignment can be performed with even higher precision.

In this way, the charged beam processing apparatus shown in this embodiment determines the spraying position of the processing gas 7 and the irradiation position of the electron beam 5, and then moves the sample stage 2 to expose the processed portion of the wafer 1. and placed at the positioning position. In this state, processing gas 7 is injected from gas nozzle 11 onto wafer 1, and electron beam 4 is irradiated to perform deposition or etching.

Although this embodiment shows an example in which the electron beam 5 is used as the charged beam, the present invention is not limited to this and may use a focused ion beam. Although the CCD 14 is used as a position sensor, any sensor can be used as long as it can two-dimensionally detect the laser beam 13 and the charged beam (electron beam 5 or focused ion beam). The same effect can be obtained. Furthermore, in this embodiment, an example in which the wafer 1 is processed has been described, but the workpiece may be a photomask in addition to the wafer 1.

Furthermore, in the above embodiment, the position of gas spraying is detected using the laser beam 13 that has passed through the gas nozzle 11, but as shown in FIG. The direction of the gas nozzle 11 (the position of the spraying of the processing gas 7) can also be detected using this method.

FIG. 3 is a sectional view showing a schematic configuration of another embodiment. In the same figure, the same or equivalent members as those explained in FIGS. is omitted. In the charged beam processing apparatus shown in FIG.
A laser beam irradiation device (not shown) is arranged at a position spaced apart from the gas nozzle 11 so that the laser beam is reflected by the laser beam and enters the CGD 14 . That is, in the charged beam processing apparatus configured in this way, the CCD 14 and the laser beam irradiation device are fixed in the sample chamber, and the CCD 1
The direction of the gas nozzle 11 can be detected by checking the output of each pixel 4 and detecting the pixel 14a into which the laser beam 13 is incident. At this time, if the point on the wafer 1 where the processing gas 7 is sprayed is 20, then this point 2
Since the positional relationship between the point 20 and the pixel 14a of the CCD 14 can be determined geometrically, the direction of the gas nozzle 11 is mechanically adjusted so that this point 20 coincides with the irradiation position of the electron beam (not shown) on the wafer 1. Just adjust accordingly. Furthermore, if the position (pixel 14a) at which the laser beam 13 is incident on the CCD 14 when the position of the point 20 is made to coincide with the irradiation position of the electron beam is determined in advance, the laser beam 1
By arranging the direction of the gas nozzle 11 by 141 points so that the incident position of the electron beam 3 coincides with the pixel 14a, the position where the processing gas 7 is sprayed can match the position where the electron beam is irradiated.

In addition, although the above-mentioned embodiment shows an example in which an electron beam is used as the charged beam, the same effect can be obtained even if a focused ion beam is used. Also, CC as a position sensor
Although D14 was used, the same effect can be obtained by using any device that can detect the laser beam 13 two-dimensionally. Furthermore, in the above-described embodiment, an example in which the wafer 1 is processed has been described, but the workpiece may be a photomask in addition to the wafer 1.

In the two embodiments described above, the diameter of the laser beam 13 is
Although the case where the diameter of the laser beam 13 is larger than the pixel size of the CCD 14 has been described, the position of the pixel corresponding to the center of the laser beam 13 can be determined from the output distribution of each pixel. Note that this means that the irradiation position of the charged beam is CC as shown in the first embodiment.
This can also be done when detecting by D14, and even if the diameter of the charged beam is larger than that of the pixel, the position of the pixel corresponding to the center of the charged beam can be determined.

〔Effect of the invention〕

As explained above, the charged beam processing apparatus according to the present invention includes a laser beam irradiation device in which the direction of irradiation of the laser beam is changed according to the direction of the gas supply nozzle, and Gas spraying with respect to the charged beam irradiation position is equipped with a sensor that detects positional deviation and a positioning means that changes the direction of the nozzle according to the amount of deviation and positions the gas spraying position at the charged beam irradiation position. The direction of the gas supply nozzle can be detected based on the position of the laser beam incident on the laser beam, and the positioning means directs the gas supply nozzle to the charged beam irradiation position. and the irradiation position of the charged beam can be accurately positioned. Therefore, machining can always be performed at the maximum machining speed, and furthermore, machining conditions can be prevented from changing even when the gas supply nozzle is replaced.

[Brief explanation of the drawing]

FIG. 1 is an enlarged perspective view of the main parts of a charged beam processing device according to the present invention, FIG. 2 is a perspective view of a sample stage used in the charged beam processing device according to the present invention, and FIG. FIG. 4 is a cross-sectional view showing the schematic structure of a conventional charged beam processing device, and FIG. 5 is a cross-sectional view showing the schematic structure of a conventional charged beam processing device. In the cross-sectional views, (a) shows the case where the processing gas is supplied to the front side of the irradiation position of the charged beam, and (b)
) similarly shows the case where the processing gas is supplied to the back side from the irradiation position of the charged beam, and the same figure (c) shows the state where the processing gas is supplied to the proper position. 1... Semiconductor wafer, 5... Electron beam, 7...
... Processing gas, 11... Gas nozzle, 13...
...Laser light, 14...CCD.

Claims (1)

[Claims] A charged beam processing device that sprays a processing gas onto a workpiece and irradiates a charged beam with the laser beam irradiation device in which the direction of laser light irradiation is changed depending on the orientation of a gas supply nozzle; A sensor detects the deviation of the gas spraying position from the charged beam irradiation position depending on the laser beam incident position, and the nozzle direction is changed according to the amount of deviation to position the gas spraying position at the charged beam irradiation position. A charged beam processing device comprising: positioning means.