Abstract: An optical waveguide chip including a core portion as an optical waveguide, a clad portion composed of a lower clad layer and an upper clad layer, and an optical fiber guide portion which is formed integrally with the clad portion for positioning a single-mode optical fiber which is to be connected with the core portion. Each portion of the optical waveguide chip is formed by creating a layer of a radiation-sensitive polysiloxane composition by photolithography. At least two kinds of radiation-sensitive polysiloxane compositions are used so that the core portion has a higher refractive index than the clad portion.

Abstract: An optical waveguide chip having an optical waveguide which can keep good transmission characteristics stably over a long period of time without separations or cracks even in severe use conditions, and an optical fiber guide portion formed without cracks firmly with a shape and a size corresponding to those of an optical fiber is provided. An optical waveguide chip 1 has a support 2, an optical waveguide 3 having a core portion 7, clad layers 6 and 8, an optical fiber guide portion 4 for positioning an optical fiber to be connected with the optical waveguide 3, and a cover member (glass plate) 5. The optical waveguide 3 is made of a radiation-sensitive polysiloxane composition. The optical fiber guide portion 4 is made of the same or a different radiation-sensitive polysiloxane composition as/from the material of the optical waveguide 3. The optical waveguide 3 and the optical fiber guide portion 4 are formed by separate processes.

Abstract: A polymer optical waveguide of the present invention has a lower clad layer, a core layer and an upper clad layer that are provided on a substrate, and a cover member that covers at least one part of the upper clad layer. The upper clad layer and the cover member are fixed together by a radiation-curable adhesive. The cover member comprises quartz or glass. According to this polymer optical waveguide, moisture absorption through the upper clad layer can be prevented, deterioration in adhesive property to the substrate or changes in characteristics due to moisture absorption of materials can be suppressed even under severe environmental conditions, and there is no deterioration in optical characteristics between before and after reliability tests, and hence sufficient reliability can be secured, and the polymer optical waveguide has stable transmission characteristics.

Abstract: An optical waveguide chip including a core portion as an optical waveguide, a clad portion composed of a lower clad layer and an upper clad layer, and an optical fiber guide portion which is formed integrally with the clad portion for positioning a single-mode optical fiber which is to be connected with the core portion. Each portion of the optical waveguide chip is formed by creating a layer of a radiation-sensitive polysiloxane composition by photolithography. At least two kinds of radiation-sensitive polysiloxane compositions are used so that the core portion has a higher refractive index than the clad portion.

Abstract: A radiation-curable composition containing (A) hydrolyzates of hydrolyzable silane compounds represented by general formula (1): (R1)p(R2)qSi(X)4-p-q (wherein R1 is a non-hydrolyzable organic group having 1 to 12 carbon atoms that contains fluorine atoms, R2 is a non-hydrolyzable organic group having 1 to 12 carbon atoms (but excluding ones that contain fluorine atoms), X is a hydrolyzable group, p is an integer of 1 or 2, and q is an integer of 0 or 1) and condensates of such hydrolyzates, and (B) a photo acid generator, wherein the ratio of silanol (Si—OH) groups in the composition is 0.1 to 0.5 out of all the bonding groups on Si. With such a composition, the waveguide loss is low for light having a wavelength in a broad range from the visible region to the near infrared region, and moreover the cracking resistance, the patterning ability upon irradiation with radiation, and so on are excellent.

Abstract: A radiation-curable composition containing (A) hydrolyzates of hydrolyzable silane compounds represented by general formula (1): (R1)p(R2)qSi(X)4-p-q (wherein R1 is a non-hydrolyzable organic group having 1 to 12 carbon atoms that contains fluorine atoms, R2 is a non-hydrolyzable organic group having 1 to 12 carbon atoms (but excluding ones that contain fluorine atoms), X is a hydrolyzable group, p is an integer of 1 or 2, and q is an integer of 0 or 1) and condensates of such hydrolyzates, and (B) a photo acid generator, wherein the ratio of silanol (Si—OH) groups in the composition is 0.1 to 0.5 out of all the bonding groups on Si. With such a composition, the waveguide loss is low for light having a wavelength in a broad range from the visible region to the near infrared region, and moreover the cracking resistance, the patterning ability upon irradiation with radiation, and so on are excellent.

Abstract: A positive-tone radiation-sensitive composition including: (A) at least one compound selected from the group consisting of a hydrolyzable silane compound represented by general formula (R1)pSi(X)4?p (wherein R1 is a non-hydrolyzable organic group having 1 to 12 carbon atoms, X is a hydrolyzable group, and p is an integer from 0 to 3), hydrolyzates thereof and condensates thereof; (B) a photoacid generator; and (C) a basic compound. A cured product that is excellent in terms of pattern precision and so on can be obtained by using the composition. The composition can be used as a material for forming optical waveguides.

Abstract: A positive-tone radiation-sensitive composition including: (A) at least one compound selected from the group consisting of a hydrolyzable silane compound represented by general formula (R1)pSi(X)4-p (wherein R1 is a non-hydrolyzable organic group having 1 to 12 carbon atoms, X is a hydrolyzable group, and p is an integer from 0 to 3), hydrolyzates thereof and condensates thereof; (B) a photoacid generator; and (C) a basic compound. A cured product that is excellent in terms of pattern precision and so on can be obtained by using the composition. The composition can be used as a material for forming optical waveguides.

Abstract: A composition for film formation which is useful as an interlayer insulating film material in the production of semiconductor devices and the like, and gives a coating film having excellent uniformity, low dielectric constant, low leakage current and excellent storage stability; and a material for insulating film formation using the composition. The composition comprises (A) a product of hydrolysis and condensation obtained by hydrolyzing and condensing at least one compound selected from the group consisting of (A-1) compounds represented by the formula (1): R1aSi(OR2)4−a, and (A-2) compounds represented by the formula (2): R3b(R4O)3−bSi—(R7)d—Si(OR5)3−cR6c; and (B) a compound represented by the formula (3): R8O (CHCH3CH2O)eR9.