Abstract: A process for the production of thin film transistor with a double gate and an optical mask consisting of depositing a conductive source and drain layer on an insulating substrate (31), producing photosensitive resin patterns fixing the location of the source and drain (34), etching the conductive layer, depositing on the structure obtained an opaque metal layer for forming the lower gate (42), carrying out thermal contraction of the resin patterns, depositing in isotropic manner a preferably a-C:H layer (39), dissolving the resin patterns, depositing a semiconductor layer (44), an insulating layer (45) and then a conductive layer (46) for producing the upper gate of the transistor and photoetching the stack formed by the conductive layer, the semiconducting layer and the insulating layer in order to fix the transistor dimensions and passivate the structure obtained with an electrical insulant (48).

Abstract: The apparatus incorporates a h.f. source (2), a plasma enclosure ( 4 ) having gas supplies, a vacuum pump (50), elements for coupling the source to the plasma enclosure, which is of a non-radiating type and which is shaped like a rectangular parallelepiped with first and second dielectric material faces parallel to the direction of the magnetic field and a third face having a rectangular opening (14) parallel to said field for forming a ribbon-like plasma, a treatment enclosure containing a mobile sample holder (18) communicating via the opening with the plasma enclosure. The coupling means have two linear waveguides (30, 38 ) with a rectangular cross-section oriented in the wave propagation direction and located on either side of the plasma enclosure, a horn (36) for coupling one of the guides to the plasma enclosure, whose cross-section widens in the magnetic field direction, the other guide being provided with a short-circuit (46).

Abstract: This color display structure for color display purposes has a first and second spaced, transparent substrates, between which is interposed a liquid crystal film (6), the first substrate (2) essentially supporting color filters (124) resistant to high temperatures and separated by black matrixes (126), a first transparent, passivating layer (128) deposited on the entire surface occupied by the filters and the black matrixes, thin film transistors (8, 9), formed on the first passivating layer facing the black matrixes so as to be protected from the ambient light, first transparent capacitor plates (10) formed on the first passivating layer facing the color filters and connected to the transistors, electrode rows (14) and columns (12) for controlling these transistors and a second transparent passivating layer (20) covering the transistors, the first plates, the rows and the columns, the second substrate (4) essentially having the second transparent capacitor plate.

Abstract: Process for the local passivation of a substrate by a hydrogenated amorphous carbon layer and process for producing thin film transistors on said passivated substrate. The local passivation process consists of producing photosensitive resin patterns (3) on the substrate (1), subjecting the structure obtained to a radio-frequency plasma essentially constituted by a hydrocarbon for thus depositing a hydrogenated amorphous carbon layer (6) on the structure and dissolving the resin patterns (3) in order to eliminate the amorphous carbon deposited on the resin, the amorphous carbon deposited on the substrate constituting the said passivation.

Abstract: The process of the invention consists of subjecting a metal oxide coating (106, 108), located on a glass substrate (100), to the action of a gaseous plasma (109) containing 10 to 88% by volume of hydrogen, 2 to 30% by volume of a hydrocarbon and 10 to 50% of an inert vector gas, bringing about the formation of a polymer coating (110) on the parts of the substrate not provided with oxide, by dissocation of the gaseous mixture, and the partial chemical etching of the oxide (106, 108) by the formation of organometallic compounds.

Abstract: Process for producing a wall for an active matrix display screen.By a first etching is formed stack rows of layers (L) with a metal at the ttom. The gaps between the rows are filled by a negative polyimide. On the surface are etched columns (C) and blocks (P). These elements serve as a mask for an etching leaving control transistors in a gate configuration below the same.Application to the production of liquid crystal display screens.