JPH0458015B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for modifying a pattern formed on a sample surface by localized spraying of an organic gas and irradiation with an ion beam.

[Prior art and its drawbacks]

Masks and reticles used in the semiconductor manufacturing process are manufactured by exposing and etching patterns, but there are two types of pattern defects: one is where areas that should have been removed remain. , and the other is one where the parts that should remain have been removed. Conventional laser mask repair equipment irradiates the remaining part of the patterned film with laser light and evaporates it, so it is possible to repair the former defect, but is powerless against the latter defect. It was hot. When repairing the latter defect, apply a resist film to the entire surface of the mask again, bake it, expose only the area to be filled, develop it, and then apply a metal or metal oxide film. One cycle was completed by performing the following steps and then performing lift-off. This method requires a significant portion of the mask manufacturing process to be repeated in order to repair the mask, which is time consuming. Moreover, since new defects may be generated by re-etching during repair, it is necessary to re-inspect after repair and, in some cases, perform repair again, which requires a great deal of time and effort.

[Object of the present invention]

The present invention was made to eliminate the drawbacks of the conventional repair methods as described above, and aims to reliably repair missing defects on a mask or reticle in a short time.

〔Example〕

Hereinafter, embodiments of a processing apparatus using a charged particle beam (ion beam) will be described in detail based on the drawings. In Figure 1, 1 is a vacuum chamber for keeping the inside at 10 ^-6 Torr or less, 2 is an exhaust system for exhausting gas from vacuum chamber 1, and 3 is a charged particle generation source provided inside vacuum chamber 1. ,
Reference numeral 4 denotes a charged particle optical system for focusing and scanning the charged particles A generated from the charged particle generation source 3, and 5 indicates a sample made of glass, metal patterns, etc., which is irradiated with the charged particle beam B from the charged particle optical system 4. ,
6 is a sample stand for placing the sample 5; 7 is a sample stand drive system for moving and positioning the sample stand 6; 8 is a sample stand drive system for moving and positioning the sample stand 6;
9 is the laser light source for irradiating the sample 5 with the laser beam L, and 9 is the laser beam L transmitted through the sample 5.
10 is a laser light detection system for detecting the laser light L from the mirror 9, and these laser light source 8, mirror 9, and laser light detection system constitute observation means for the sample 5. There is. Reference numeral 11 denotes a partition for dividing the inside of the vacuum chamber 1, and the partition 11 forms a charged particle optical system chamber 12 and a sample chamber 13. 11a
is a small hole with an inner diameter of 1 mm or less through which the charged particle beam B passes. 14 is an organic gas supply source, which supplies the sample 5 through a variable leak valve 15 and an organic gas spraying nozzle 16.
The organic gas G is concentrated at the charged particle beam irradiation position.
It's starting to spray. 17 is sample chamber 1
This is an exhaust system to keep 3 in a vacuum.

Next, the operation of the apparatus of the present invention will be explained with reference to the detailed sectional view of FIG. A mask or reticle 5 as a sample set on a sample stage 6 whose position can be moved by a sample stage drive system 7 is irradiated with laser light L, and the transmitted light is detected by a laser light detection system 10. Pattern 5 on the sample
2 is observed. Defects in the pattern 52 are detected by comparing the pattern 52 measured with the laser beam L with patterns stored in advance. For defects in the pattern 52 that remain, after coarse adjustment is made by the sample stage drive system 7, fine positioning of the point to be irradiated with the charged particle beam B is performed by the charged particle optical system 4. After that, the process is performed using an accelerating voltage that obtains the energy that maximizes the spatter rate of the pattern. This ion beam irradiation sputters and removes unnecessary residue. Furthermore, for the defect 53 that was created when the remaining portion of the pattern 52 on the glass substrate 51 shown in FIG. After finely positioning the irradiation position using the optical system 4, the sample chamber 13 is connected to the organic gas supply means 14, 15.
and 16 to create an organic gas atmosphere. The acceleration energy of the charged particle beam B at this time effectively decomposes the organic gas molecules g constituting the organic gas G. Set between 1Kev and 200KeV. The organic gas molecules g collide with the charged particle beam B to become decomposed substances g', which adhere to the pattern defect positions 53 on the sample so as to accumulate, and some of them are carbonized. In order to quickly carry out additional corrections as described above, it is necessary to set the pressure at the correction position to an organic gas atmosphere of about 10 ^-2 Torr to 1 Torr and supply a sufficient amount of organic molecules. On the other hand, in order to protect the charged particle source 3 and minimize scattering of the charged particle beam B, the pressure of the charged particle source 3 and the charged particle optical system 4 must be set to 10 ^-6
Must be less than Torr. In view of these requirements, a partition 11 having a small hole 11a with an inner diameter of 1 mm or less through which the charged particle beam B passes is provided between the charged particle optical system 4 and the sample 5, and a charged particle optical system chamber 12 and a sample chamber 13 are provided. It is necessary to separate them and perform differential exhaust in the exhaust system 2 and the exhaust system 17, respectively.
In order to carry out additional corrections more quickly, in addition to the above-mentioned differential pumping means, an organic gas blowing nozzle 16 is provided near the charged particle beam irradiation position to intensively supply organic gas molecules to the defect position. . Note that the distance between the organic gas blowing nozzle 16 and the charged particle irradiation position is less than the mean free path of organic gas molecules in the sample chamber, and the sample chamber 13 is 10 ^-3 Torr.
When , it corresponds to 5 mm or less. If the above conditions are not satisfied, organic gas molecules will not be effectively supplied due to scattering by gas molecules within the sample chamber.

〔Effect of the invention〕

As described above, processing equipment using a charged particle beam performs observation, removal correction, and additional correction of defects in the pattern of a mask or reticle in one process, and can correct one mask. It can be completed in an extremely short time. This means that each cycle for additional corrections takes approximately half a day, whereas conventional inspection, cleaning, baking, exposure, development, and
This is a dramatic improvement compared to membrane deposition and lift-off. By adopting the present invention, it is expected that the mask manufacturing process will be simplified and the finished mask will be of good quality.

The organic gases used in this example include phenanthrene, pyrene, methylphenanthrene,
It is effective when one or more of fluoranthene, anthrone, and triphenylmethane are used.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a processing apparatus using a charged particle beam, and FIG. 2 is a detailed sectional view for explaining the development of the main part of FIG. 1. 1... Vacuum chamber, 2... Exhaust system, 3...
Charged particle generation source, 4... Charged particle optical system, 5...
Sample, 6...Sample stand, 7...Sample stand drive system, 8...
... Laser light source, 9 ... Mirror, 10 ... Laser light detection system, 11 ... Partition, 11a ... Small hole,
12...Charged particle optical system room, 13...Sample room, 1
4...Organic gas supply source, 15...Variable leak valve, 16...Organic gas spray nozzle,
17... Exhaust system, A... Charged particles, B... Charged particle beam, L... Laser light, G... Organic gas,
g...Organic gas molecules, g'...Organic gas decomposition substances,
51...Glass substrate, 52...Metal pattern, 5
3...Position of defect in metal film.

Claims (1)

[Claims] 1. Ions are generated from a charged particle source, and the ions are narrowed down by a charged particle optical system to form an ion beam, and while the ion beam is scanned, it is irradiated to the defect position of a pattern formed on the sample surface, and the defect position of the pattern formed on the sample surface is irradiated. In addition, ions are generated from a charged particle source, and a charged particle optical system narrows the ions into an ion beam by scanning the ion beam to remove the pattern formed on the sample surface. The ion beam is irradiated to the defect position, and the distance between the ion beam irradiation position and the tip of the nozzle for spraying the organic gas is set to 5 mm or less, and the organic gas is intensively applied to the ion beam irradiation area of the defect among the defects at the same time as the ion beam irradiation. A pattern correction method comprising the step of additionally correcting missing defects in the pattern by spraying on the pattern.