JPS5979531A - Forming method of thin-film - Google Patents

Abstract

PURPOSE:To obtain an insulating film for isolating an element through a direct drawing without using a photoetching method, etc. by irradiating laser beams to the desired section of a Si film coated on the surface of a substrate in an atmosphere containing O2 and N2 when the insulating film is formed to the desired section of the Si film. CONSTITUTION:The Si substrate 1 is coated with a SiO2 film 2, a MoSi2 film 3 is laminated on the film 2, and the polycrystalline Si thin-film 4 is formed on the film 3. A holding base 6 supporting the substrate 1 is set up in an irradiating-box outer wall 5 with a gas inflow port 10 and a gas outflow port 11, the substrate 1 is placed on the base 6 while the film 4 is directed upward, and an irradiating window 9 made of quartz is fitted to the opening section of the upper end of the outer wall 5. Laser beams are projected to the window in the vertical direction 7, and scanned in the horizontal direction 8 to irradiate the desired section of the film 4. Accordingly, the irradiating section of the film 4 is changed directly into the insulating film, and a manufacturing process for the element is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for forming an insulator film, and more specifically, a semiconductor film temporarily deposited on a substrate surface is exposed to a laser beam in a controlled atmosphere. The present invention relates to a method of irradiating the semiconductor film to make the irradiated portion of the semiconductor film an insulator.

CvE Next Technology] As is well known, insulator thin films on semiconductor surfaces can be formed by various methods, and there are various usage names. For example, the most widely used method is thermal oxidation, in which the substrate is heated to a high temperature in a saponifying atmosphere, such as boron containing dry oxygen-PI (ZO), vapor phase growth, thermal decomposition, etc. Methods such as sputtering to deposit on the surface of water bodies are also used. For crabmide films, nitridation of the substrate surface by heating, especially at high temperatures, is also used, as well as other methods such as vapor phase growth or sputtering. It is common to use a deposited film r.

Conventionally, these sample forming techniques have been characterized by forming a film of uniform thickness on the substrate by raising the temperature over the entire substrate using a unique method. The formation of the pattern necessary to form a finely-sized half-inscription tower has been carried out by applying photolithography to the film uniformly formed in this way.

Lately, with the progress of temporary assembling of Takako and high-quality lamination over the years, the so-called direct drawing method, which forms the necessary stamps on the surface of the substrate, regardless of the photographic engraving method, was used to form the elements of the glaze. Tsukuame is realized through the manufacturing process. In the field of loquat film formation, which is the subject of the present invention, film deposition technology using a vapor phase growth method using laser light has been developed (e.g., P., K., Boye et al.
r et al., Appz.

Phys, Lett, 40. (8), 71(j,
15 Apr+t'82).

However, there are no known examples of directly oxidizing or nitriding the silicon of the substrate as in thermal oxidation.

[Object of the Invention] The object of the present invention is to provide a method for selectively forming an oxidation or nitride film directly on any localized area on the surface of a semi-woven body.

[Summary of redundancy]

”・Insulation to the substrate surface by vapor phase growth method)
Laser for deposition of 1s? Although it is known how to use it,
There is no need for a film forming technology that can be used horizontally with the direct drawing method. In some methods, the purpose is to inactivate the surface (deposited film type).
In the case of the gate insulating film of an insulator, the goal can be achieved by performing direct writing once, but in cases where the goal is isolation between elements, -
Is this by direct drawing? It is clear that this cannot be achieved.

(b5) In such a case, if the isolation between the elements is performed by insulation by a deposition method, it is necessary to at least increase the height V as described below. In the first step, etching the gap areas to be performed on the substrate (7) in advance (forming 4 grooves, and applying fertilization to the grooves)
It's a way to get used to it. The second method is to insulate the part to be formed into a semi-convoluted body (for example, using the Evita Senshal growth method), and then insulate the area for an element weight of 91W after the formation. Membrane τ'■ Mewa in the way to bond.

As is clear from what has been described above, isolation between elements is performed using the deposition method 1e method V, a film, etc.
In some cases, it is necessary to pre-form or draw the pattern required for element separation twice, which naturally increases the number of steps, and at the same time increases the need for detailed patterning and patterning. On the other hand, insulating films formed by directly converting or Europeanizing some semiconductor devices have a high temperature of 70%, such as Panosybe=7yon.
In addition to being used for finding 1 shaku and 4/l by the i-selection method, it is effective for elbows when used for separation between elements, and semiconductor rope X (#
We are looking forward to seeing improvements in the delivery process.

That is, if direct oxidation (or nitridation) is performed, a part of the surface of the substrate will become a part of the substrate, so that the isolation between elements will be reduced.
Is it possible to separate between macromolecules by drawing only one time to the tal 1 minute that should be formed in the Q area? When it comes to aligning minute patterns and avoiding delays in the process, you can rely on your dog.

Although this method of directly converting an arbitrary semiconductor surface region into an insulator is useful, methods other than the so-called thermal ridge formation method that allow contact drawing using a beam of energy such as a laser are non-OJ. There were a lot of them. In other words, a pulsed laser source! - When the roots were irradiated, a large amount of oxygen was detected, but the oxidized gas was not criticized.

711) The reaction with the 1,400 yen body is that the semiconductor head has sufficient strength to maintain its shape at the melting point of the 1,000 yen body. Material with low δ
If it is a thin film formed on the substrate formed in this way, an oxide film, a nitride film, or a nitride film can be formed by laser irradiation in an acid-based, silica-based, or both atmosphere. This is based on Saru's new foresight.

EXAMPLE Hereinafter, one embodiment of the present invention will be explained with reference to FIG. In FIG. 1, the substrate is a silicon single crystal plate l. Its main surface is coated with S 1O2ii≠ (thickness 200
nm) 2 is formed, and a molybdenum silicide (MOSi2) film 3 formed by sputtering and having an IC thickness of 30Q nm is adhered. A polycrystalline silicon thin film 4r having a thickness of 10 nm was deposited on this molybdenum/silicide film by the low pressure CV JJ method, as shown in FIG.

Next, a laser beam was irradiated onto Hakuzo shown in Figure 1. The second conceptual diagram of the irradiation device is shown in Figure V. The base is installed in a box 5 that can control the air inside, and has a heatable droplet base 6.
By scanning a finely focused laser beam 77 relative to the substrate, the desired position of the substrate is determined. It is now possible to irradiate. The irradiation conditions r will be described below.

The atmosphere vi is N2 at about 1 atm, flowing into and out of the irradiated surface at a flow rate of 1.5 tons per 7゛υ. Due to the continuous true life, 4
It is kept on a holding rack heated to 00C.

The laser was a continuous-wave (CW) argon ion laser, which was adjusted by an optical system to have a diameter of approximately 60 μm at the substrate position. Rail “-scan speed 1 to 1
The internal shape of the substrate hole fiQ f l of the irradiation wi varied variously between 00 cm/s and the results shown in Fig. 3 were obtained.
A good trap. 9 If you keep the fixed feeding speed at a constant rate, you won't notice any change in the polycrystalline silicon layer when using a low-power siege, but when you use a 1'fiJ high-power IJ.
Formation of a nitride film was observed.・In the region ■ of Ishini's power, the destruction of the molybdenum silicide tribe occurred. At a set meal speed of 10 twr/s, the Koi of area ■ and Hanakiri ■ was approximately 4W, and the boundary between area J1 and head Ill was met at 9W.

A similar effect can be obtained by using Kuntal silicide (TaS 12) or tungsten silicide (WS+z)' instead of molybdenum silicide. Obtained absolute 7. It was used as an insulating film between scraps for panovation and polyphonic wiring.

Another example of this example is alumina single crystal (sapphire)
This relates to an epitaxial silicon I-bamboo crystal layer formed on a substrate. The epitaxial layer was formed to a thickness of 15 nm by a conventional, well-known vapor phase growth method. The substrate V with this epitaxial silicon monocrystalline layer t,
Said fruit 77I! Similarly at i second 12, #400L in the air control port I function 1 or j? The atmosphere, which was maintained by vacuum absorption on a heated medical table, was 3% argon, with a flow rate of J-t per minute. (Direction 1 of argon ion Rayleigh < + = 1 on the busy substrate surface
Set to 0 μm VC tone 1, set feeding speed ml 50 cm/s
When irradiated with laser power of 1.5 to 2 W, it was possible to obtain a band-shaped acid film with a width of 3 to 57 days in just a few seconds. A cross-section of the substrate after irradiation of 13η is shown in FIG. As shown in pronation (b), V, oxide film 15
It is clear that if the surrounding area of the desired area is irradiated in this embodiment, the area can be separated into an independent device value range. Is this also a vague way of saying this?
Confirmed by Ushi, it was.

Under the above conditions, in each of the two directions for direct firing, the interval is 50 mm.
When I did the irradiation at t + m, the size was about 4
5μm x 45μm! A monocrystalline silicon region was obtained which was separated by oxidation of 100% to L. Next, when we measured the leakage current τ between adjacent single crystal regions, we found that t(*b
t=t 5 V vc Y: 10-'' A The fc oxide film formed by the method of this example had characteristics t sufficient for photon separation.

In addition, in this example, by using nitrogen instead of oxygen as the atmospheric gas, the nitride film could be formed under the same conditions. was able to form. That is, even if a mixed gas r of an inert gas such as argon and oxygen or nitrogen was used as the atmospheric gas instead of pure oxygen or pure nitrogen, the effects of the present invention were not impaired in any way.

The present invention was also effective for silicon thin films coated on amorphous insulating substrates. In other words, the original large crystals (grain size 100 μm) formed as a bath-fused silica substrate.
In a silicon thin film consisting of grains, region separation 7 due to the insulator V could be performed under conditions almost the same as in the previous example.

[Young fruit of the invention] According to the present invention, minute molecules on the surface of a semiconductor can be
By performing rvN, it is possible to form the desired head-mounted insulating film, so local formation of isolation between elements and other insulating glands is performed.Accompanying with the photo-etching method of photon gas + 4 cloth, exposure, actual urine, and etching, ]] I am busy with one step and draw directly Ll
! Since it can be formed by the IT method, it has the advantage of simplifying the photon manufacturing process and indirectly improving economic efficiency due to gradual and improved device yield.

[Brief explanation of drawings]

Figure 1 is a vertical sectional view of the sample for the first embodiment, Figure 2 is a cross-sectional view of the sample chamber for laser irradiation, and
Figure 13 is a graph showing the irradiation effect of the irradiation parameter l(5<).
FIG. ■...Silicon single crystal substrate, 2...Thermal oxidation 5IU2
jru bed 3...mo 1.1bu, den silicide I exchange, 4
... Polycrystalline silicon thin film, 5... Ken outside the irradiation box, 6.
・・Test that can be heated, 1F holding table, 7...Laser・
Beam incidence direction, 8... -59 in the fixed meal direction... Quartz irradiation m, 10... Gas inlet, 11 ・Gas outflow 1
ml, 12...Water cooling pipe, 13-15...Region r indicating different irradiation effects, 16...Sapphire crystal group 14.17...Polycrystalline silicon film, ■1 Figure z Figure 3 Figure height Figure 4

Claims (1)

[Claims] Laser light on a desired part of silicon in an atmosphere containing oxygen and/or nitrogen? Is it possible to insulate the desired part by irradiating it? Characteristic thin film formation method.