JPH0525282A - Organosilicon polymer and its preparation - Google Patents

Abstract

PURPOSE:To prepare an organosilicon polymer which consists mainly of a polymethylphenylsilane structure and is expected to be used as a photoresist, a optical waveguide material, a precursor of silicon carbide, a semiconductor, an electrophotographic photoreceptor, a nonlinear optical material, and a luminescent material. CONSTITUTION:The objective organosilicon polymer which includes a polymethylphenylsilane structure and has a wt.- average mol.wt. (by gel permeation chromatography, in terms of monodispersed PS) of at least 2,000 and a peak at about -60 to -80ppm or at about -42 to -50ppm or at about -30 to -35ppm, in addition to the peak characteristic of polymethylphenylsilane at -40ppm, in <29>Si-FTNMR (in a chloroform soln., in terms of tetramethylsilane) is prepd. by condensing methylphenyldichlorosilane with phenyltrichlorosilane in the presence of a metallic sodium.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a conventional polymer material having a carbon skeleton as a photoresist, an optical waveguide material, a precursor of silicon carbide, a semiconductor, an electrophotographic photoreceptor, a non-linear optical material and a light emitting material. The present invention relates to a soluble organic polysilylene polymer having a silicon skeleton, which is a new type of functional material having unique characteristics that cannot be found in.

[0002]

2. Description of the Related Art In recent years, soluble organic polysilylene, which is a polymer having a silicon skeleton, has been used as a photoresist, an optical waveguide material, a precursor of silicon carbide, a semiconductor, an electrophotographic photoreceptor, a non-linear optical material, and a carbon as a light emitting material. It has attracted a lot of attention as a new type of functional material with unique characteristics not found in conventional polymer materials with a skeleton. One of the causes of interest in organic polysilylene is that it dissolves in organic solvents and can be easily processed into fibers and thin films. However, most of the organic polysilylenes known so far have a chemical structure having a repeating unit of (SiR ₁ R ₂ ) (R ₁ and R ₂ are organic substituents) in which _two organic substituents are introduced into Si. . Therefore, for example, the sensitivity is insufficient for processing a thin film having a thickness of about several microns such as a photoresist or an optical waveguide using a photochemical cleavage reaction or a crosslinking reaction, and Si-appearing in the vicinity of 300 to 400 nm. Since the film thickness cannot be increased due to self-absorption due to the strong ultraviolet absorption band derived from Si bond, the characteristics were not satisfactory as compared with the conventional carbon-based polymer material. In order to achieve high sensitivity, it is necessary that the polymer has a photochemically active Si—Si bond. Further, as a conventionally known visible light emitting silicon material, a wavelength of 420
To polymethylphenylsilane and network alkylpolysilin having an emission region of 500 nm from [Kagawa Kawa. (Kagawa, T.) and others, Solid State Commun., 57th
Vol., P. 635 (1986), Furukawa K .; (Furukawa,
K. ) In addition, Macromolecules (Macromolecules
), 23, 3423 (1990)].

[0003]

However, polymethylphenylsilane has a strong emission around 350 nm.
It had a drawback that the emission intensity from 20 to 500 nm was relatively weak. The network alkyl polysilin has a drawback that it lacks mechanical properties because it has only alkyl substituents and is extremely deteriorated. The object of the present invention is to provide a photoresist, an optical waveguide material, a precursor of silicon carbide, a semiconductor, an electrophotographic photoreceptor, a non-linear optical material, and an organosilicon polymer whose base material is polymethylphenylsilane, which is expected as a light emitting material. To provide.

[0004]

The first aspect of the present invention is an invention relating to an organosilicon polymer, in which an organosilicon polymer containing a polymethylphenylsilane structure is used as a monodisperse polystyrene. The weight average molecular weight is 2000 or more and ²⁹ Si is determined by the gel permeation chromatography method based on
-FTNMR (in chloroform solution, based on tetramethylsilane) -60 to -80 or -42 to -50
Alternatively, it is characterized by having a peak near −30 to −35 ppm other than −40 ppm, which is characteristic of polymethylphenylsilane. A second invention of the present invention is an invention relating to a method for producing an organosilicon polymer, wherein 0.01 to 0.50 of phenyltrichlorosilane is present in a mole fraction with respect to methylphenyldichlorosilane,
It is characterized by being produced by desalting condensation in the presence of sodium metal.

An important concept of the present invention is that the introduction of an aromatic-substituted silin to the methylphenylpolysilylene structure results in localization in the band structure of a one-dimensional semiconductor composed of Si--Si chains. It is to form a level or to promote localization of Si bond electrons.
Therefore, as the aromatic ring, not only the phenyl group mentioned here but also any condensed polycyclic structure such as a naphthyl group, anthryl group and pyrenyl group may be used. Further, these phenyl group, naphthyl group, anthryl group, pyrenyl group and the like may have an appropriate aliphatic substituent.

In the same manner as shown in the following examples and application examples, when the emission spectrum of the organosilicon polymer copolymer having another organosilicon polymer copolymer composition was examined, a wide emission band was found. In order to obtain it, the ratio of phenyltrichlorosilane to methylphenyldichlorosilane is 0.001 to 0.50, preferably 0.01 to 0.10, although it depends strongly on the mole fraction of copolymerization. I found out. When the value exceeds 0.10, oxidative deterioration is likely to occur, which is not suitable as a light emitting material. On the other hand, the oxidative deterioration characteristics of organic silicon polymer copolymers having other organic silicon polymer copolymer compositions are related to the formation of resists and waveguides, but the values are 0.001 to 0. It was found that if it is 50, preferably 0.01 or more, the decomposition is promoted with good sensitivity. As described above, by incorporating the phenylcillin structure into the main chain structure of the polymethylphenylsilane homopolymer, it becomes possible to control the light emission characteristics, the photodegradation characteristics, and the oxidation deterioration characteristics.

[0007]

EXAMPLES The present invention will be described in more detail below by way of examples and application examples, but the present invention is not limited to these.

Example 1 Hereinafter, the present invention will be described more specifically with reference to synthesis examples.
All reaction operations and purification operations were performed under an argon gas atmosphere and with room light cut off. The inside of the reaction vessel was thoroughly dehydrated and degassed, and the atmosphere was replaced with argon gas. Then, 3.8 g of a metal sodium dispersion liquid (toluene 30%) and 50 ml of toluene were placed in the flask. At an oil bath temperature of 110 ° C., a mixed monomer of methylphenyldichlorosilane (1) (5.62 g) and phenyltrichlorosilane (2) (0.13 g) was added all at once, and the mixture was further reacted for 10 minutes. The reaction mixture solution was pressure filtered, and the filtrate was added to degassed cold isopropyl alcohol. The resulting white precipitate was collected by a centrifuge and
It was vacuum dried at ° C. The yield was 0.80 g. A monomodal polymer having a weight average molecular weight of 12,100 and a dispersity (= weight average degree of polymerization / number average degree of polymerization) of 7.2, which was obtained by gel permeation chromatography based on monodisperse polystyrene, was obtained. Was given. The obtained organosilicon polymer 3 (1/2 = 0.97 / 0.03) could be easily formed into a thin film by a spin coating method or a solvent casting method.

3 produced by the solvent casting method (1/2 =
0.97 / 0.03) and polymethylphenylsilane thin film FT-IR absorption spectrum (substrate: KBr).
And shown in FIG. That is, FIG. 1 shows that the organosilicon polymer copolymer 3 synthesized in Example 1 (1/2 = 0.97 /
0.03) FIG. 2 is a diagram showing the FT-IR absorption spectra of the polymethylphenylsilane thin film in terms of the relationship between absorbance (vertical axis) and wave number (cm ⁻¹ , horizontal axis). Attribution is as follows. Aromatic and aliphatic CH
Stretching vibration from 3100 to 2850 cm ^-1 , aromatic C = C
Stretching vibration of Si-S near 1600 to 1500 cm ^-1
i Stretching vibration appears near 450 cm ^-1 . Also, S
Almost no absorption around 1000-1100 cm ^-1 based on i-O-Si is observed. No absorption around 3300 cm ^-1 due to Si-OH stretching vibration is observed.

The obtained organosilicon polymer 3 (1/2 =
0.97 / 0.03) and electronic absorption spectrum of polymethylphenylsilane (in tetrahydrofuran solution, room temperature)
Is shown in FIGS. 3 and 4. That is, FIG. 3 shows that the organosilicon polymer copolymer 3 (1/2 = 0.
97 / 0.03) and FIG. 4 is a diagram showing the electron absorption spectra of polymethylphenylsilane as a function of absorbance (vertical axis) and energy (eV, horizontal axis). Copolymer 3 exhibits almost the same absorption spectrum as homopolymer polymethylphenylsilane.

The obtained organosilicon polymer 3 (1/2 =
0.97 / 0.03) and polymethylphenylsilane
²⁹ Si-FTNMR (proton noise decoupling method, in chloroform solution, tetramethylsilane standard) is shown in FIGS. 5 and 6. That is, FIG. 5 shows the organosilicon polymer copolymer 3 (1/2 = 0.9) synthesized in Example 1.
7 / 0.03) and FIG. 6 is a diagram showing ²⁹ Si-FTNMR of a polymethylphenylsilane thin film in terms of the relationship between signal intensity (vertical axis) and chemical shift (ppm, horizontal axis). In copolymer 3, in addition to the three strong peaks at around -40 ppm, which are characteristic of homopolymer polymethylphenylsilane, satellite peaks at around -35 ppm and -45 ppm clearly appear. This is 3
Is a small amount of branched S in the chain skeleton of polymethylphenylsilane.
It is speculated that the i structure could be introduced.

Comprehensively judging the above results, the obtained organosilicon polymer copolymer 3 (1/2 = 0.97 /
It is presumed that 0.03) can introduce a small amount of branched Si structure into the Si main chain skeleton without converting a part of the Si—Si bond into a siloxane structure.

Example 2 As in Example 1, the inside of the reaction vessel was thoroughly dehydrated and degassed, and the atmosphere was replaced with argon gas. Then, 4.4 g of a sodium metal dispersion (30% of toluene) and 50 ml of toluene were placed in a flask. At an oil bath temperature of 110 ° C., a mixed monomer of 1.90 g of methylphenyldichlorosilane (1) and 2.10 g of phenyltrichlorosilane (2) was added all at once, and after the addition, the mixture was further reacted for 10 minutes. The reaction mixture solution was pressure filtered, and the filtrate was added to degassed cold isopropyl alcohol. The resulting white precipitate was collected by a centrifuge and vacuum dried at 60 ° C. The yield was 0.40g. A unimodal polymer having a weight average molecular weight of 6690 and a dispersity (= weight average degree of polymerization / number average degree of polymerization) of 10.4 obtained by gel permeation chromatography based on monodisperse polystyrene was obtained. It was The obtained organosilicon polymer copolymer 3 (1/2 = 50/50) could be easily formed into a thin film by spin coating or solvent casting.

3 produced by the solvent casting method (1/2 =
0.50 / 0.50) FT-IR absorption spectrum (substrate: KBr) of the thin film, the absorbance (vertical axis) and wave number (cm ^-1 ,
FIG. 7 shows the relationship with (horizontal axis). Attribution is as follows. Aromatic and aliphatic CH stretching vibrations from 3100 to 2
At 850 cm ^-1 , aromatic C = C stretching vibration is 1600 to 1
500cm around ^-1, Si-Si stretching vibration appearing in the vicinity of 450 cm ^-1. In addition, stretching vibration based on Si-O-Si is recognized near 1000-1100 cm ^-1 . 3300 to 3600 cm derived from Si-OH stretching vibration
Absorption around ^-1 is observed.

Organosilicon polymer copolymer 3 obtained
The electron absorption spectrum of (1/2 = 0.50 / 0.50) (in a tetrahydrofuran solution at room temperature) is shown in FIG. 8 in terms of the relationship between absorbance (vertical axis) and energy (eV, horizontal axis). The organosilicon polymer copolymer 3 (1/2 = 0.50 / 0.50) synthesized in Example 2 has a broader absorption of 3.7 eV than the homopolymer polymethylphenylsilane. is there.

Organosilicon polymer copolymer 3 obtained
(1/2 = 0.50 / 0.50) ²⁹ Si-FT NMR
(Proton noise decoupling method, in chloroform solution, with reference to tetramethylsilane) is shown in FIG. 9 in relation to signal intensity (vertical axis) and chemical shift (ppm, horizontal axis). The organosilicon polymer copolymer 3 synthesized in Example 2 was
The peak near -40 ppm, which is characteristic of homopolymer polymethylphenylsilane, becomes broad, and in addition to that, -24 ppm, -30 ppm, -45 ppm,
Peaks appear near -70 ppm and -78 ppm. This means that 3 was able to introduce a large amount of branched Si structure into the linear skeleton of polymethylphenylsilane.

Comprehensively judging the above results, the obtained polysilylene copolymer 3 (1/2 = 0.50 / 0.5) was obtained.
It is considered that in 0), although a part of the Si—Si bond was converted into a siloxane structure, a large amount of branched Si structure could be introduced into the Si main chain skeleton. However, since its structure is highly strained and unstable, it is presumed that oxygen in the air easily caused oxidative deterioration.

Application Example 1 Organosilicon polymer copolymer 3 (1/2 = 0.
97 / 0.03) has a wide absorption over 250 to 350 nm, and therefore xenon, deuterium,
It is expected that microfabrication using an ultraviolet light source containing mercury or a strong light source such as a nitrogen laser or an excimer laser will be facilitated. In fact, it takes about 15 minutes to irradiate a thin film (thickness: about 0.3 micron) of organosilicon polymer 3 (1/2 = 0.97 / 0.03) with a mercury lamp of 254 nm wavelength (output 6 W). Light bleached. Utilizing this property, applications such as photoresists and optical waveguides are expected.

Organosilicon polymer copolymer 3 (1/2 =
0.97 / 0.03) thin film photoreaction in air at room temperature
Followed by using UV absorption spectrum. Organosilicon polymer copolymer 3 synthesized in Example 1 (1/2 = 0.9
7 / 0.03) Change in UV absorption spectrum with time of UV irradiation of thin film is shown by absorbance (vertical axis) and wavelength (nm, horizontal axis).
FIG. 10 shows the relationship with. From the UV absorption spectrum,
Si over 235 to 350 nm with light irradiation time
The broad absorption band derived from the -Si chain almost disappeared.

Further, it was traced using FT-IR. FIG. 11 shows the change with time of the FT-IR absorption spectrum due to ultraviolet irradiation in terms of the absorbance (vertical axis) and wavelength (cm ⁻¹ , horizontal axis) (wavelength: 254 nm, output 6 W, in air, room temperature).
From FT-IR, S around 2100 cm ^-1 with irradiation time
i-H stretching vibration and Si-OS near 1050 cm ^-1
Stretching vibrations due to i-bonds increased. This photo-oxidation rate was almost the same as the corresponding polymethylphenylsilane homopolymer. This means that the introduction of a small amount of phenylsilane structure does not make the main chain structure significantly unstable.

Application Example 2 Organosilicon polymer copolymer 3 (1/2 = 0.
97 / 0.03) The excitation energy dependence (measurement temperature 4K) of the emission spectra of the thin film and the polymethylphenylsilane homopolymer thin film are shown in FIGS. 12 and 13. That is, FIG. 12 shows the excitation energy dependence of the emission spectrum of the organosilicon polymer copolymer 3 (1/2 = 0.97 / 0.03) thin film synthesized in Example 1 with respect to the emission intensity (arbitrary unit, vertical axis). ) And energy (eV, horizontal axis). FIG. 13 shows the excitation energy dependence of the emission spectrum of the polymethylphenylsilane thin film as emission intensity (vertical axis) and energy (eV, horizontal axis). FIG. Compared with polymethylphenylsilane homopolymer, the organosilicon polymer copolymer 3 shows only a broad emission band of about 2.0 to 3.3 eV substantially without depending on the excitation energy.

Organosilicon polymer copolymer 3 (1/2 =
14 and 15 show the monitor energy dependence (measurement temperature 4K) of the excitation spectra of the 0.97 / 0.03) thin film and the polymethylphenylsilane homopolymer thin film. That is, FIG. 14 shows the organosilicon polymer copolymer 3 (1/2 = 0.97 / 0.03) synthesized in Example 1.
FIG. 16 is a diagram showing the monitor energy dependence of the excitation spectrum of the thin film as a relationship between the monitor intensity (vertical axis) and the energy (eV, horizontal axis). FIG. 15 shows the monitor energy dependence of the excitation spectrum of the polymethylphenylsilane thin film. It is a figure shown by the relationship between monitor intensity (arbitrary unit, a vertical axis) and energy (eV, a horizontal axis). Regarding the cause of the wide emission band around 2.0 to 3.3 eV, the organosilicon polymer copolymer 3 (1/2 = 0.97 / 0.03) is similar to the polymethylphenylsilane homopolymer in 4. Bands near 0 and 4.8 eV are involved. That is, the organosilicon polymer copolymer 3 (1/2 = 0.97 / 0.
The broad emission band of 03) means that the absorption around 3.7 eV, which was visible in the absorption spectrum, is not involved.

[0023]

As shown in the present invention, by incorporating phenyltrichlorosilane into the main chain structure by a copolymerization reaction with respect to polymethylphenylsilane homopolymer, the luminescence characteristics, photodecomposition characteristics, and oxidative deterioration characteristics can be improved. It becomes possible to control. The obtained organosilicon polymer copolymer is expected to be applied in a wide range of fields as a photoresist, an optical waveguide material, a precursor of silicon carbide, a semiconductor, an electrophotographic photoreceptor, a non-linear optical material, and a light emitting material.
In particular, since there is an absorption band based on a Si-Si chain at a wavelength of 300 to 400 nm, it is suitable for patterning a polymer thick film that does not require a sensitizer as a negative working material for microfabrication.
It is also promising as a visible light emitting material.

[Brief description of drawings]

FIG. 1 is an FT of organosilicon polymer copolymer 3 (1/2 = 0.97 / 0.03) synthesized in Example 1 of the present invention.
It is a figure which shows -IR absorption spectrum.

FIG. 2 is a diagram showing an FT-IR absorption spectrum of a polymethylphenylsilane thin film.

3 is a diagram showing an electron absorption spectrum of the organosilicon polymer copolymer 3 of FIG.

FIG. 4 is a diagram showing an electronic absorption spectrum of polymethylphenylsilane.

FIG. 5: ²⁹ Si of the organosilicon polymer copolymer 3 of FIG.
It is a figure which shows -FTNMR.

FIG. 6 ²⁹ Si-FT of polymethylphenylsilane thin film
It is a figure which shows NMR.

FIG. 7 is a diagram showing an FT-IR absorption spectrum of an organosilicon polymer copolymer 3 (1/2 = 0.50 / 0.50) thin film synthesized in Example 2 of the present invention.

8 is a diagram showing an electron absorption spectrum of the organosilicon polymer copolymer 3 of FIG. 7. FIG.

FIG. 9 is ²⁹ Si of the organosilicon polymer copolymer 3 of FIG.
It is a figure which shows -FTNMR.

FIG. 10 is a view showing a change with time of an electron absorption spectrum of the organosilicon polymer copolymer 3 thin film of FIG. 1 due to ultraviolet irradiation.

FIG. 11 is a diagram showing a time-dependent change in FT-IR absorption spectrum of the organosilicon polymer copolymer 3 thin film of FIG.

12 is a diagram showing the excitation energy dependence of the emission spectrum of the organosilicon polymer copolymer 3 thin film of FIG.

FIG. 13 is a diagram showing the excitation energy dependence of the emission spectrum of a polymethylphenylsilane thin film.

14 is a diagram showing the monitor energy dependence of the excitation spectrum of the organosilicon polymer copolymer 3 thin film of FIG.

FIG. 15 is a diagram showing monitor energy dependence of an excitation spectrum of a polymethylphenylsilane thin film.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 21/027

Claims (2)

[Claims] 1. An organosilicon polymer having a polymethylphenylsilane structure having a weight average molecular weight of 2000 or more as determined by gel permeation chromatography based on monodisperse polystyrene, and
²⁹ Si-FTNMR (in chloroform solution, based on tetramethylsilane) has peaks near −60 to −80, −42 to −50, or −30 to −35 ppm other than −40 ppm, which is characteristic of polymethylphenylsilane. An organosilicon polymer characterized in that 2. An organosilicon polymer characterized by being produced by desalting condensation in the presence of sodium metal in the presence of 0.01 to 0.50 of phenyltrichlorosilane in a mole fraction relative to methylphenyldichlorosilane. Manufacturing method.