US 5,491,571 A · Liquid crystal display including electrodes and driver devices integrally formed in monocrystalline semiconductor layer

Abstract

A silicon dioxide etch stop layer (30) is formed on an inner surface (28b) of a monocrystalline silicon layer (28), and a silicon carrier wafer (52) is bonded to the etch stop layer. The exposed inner surface (28a) of the monocrystalline layer (28) is uniformly thinned to approximately 4 micrometers. Front electrodes (20) in the form of heavily doped areas, and microelectronic transistor driver devices (42) for the electrodes (20) are integrally formed on the outer surface (28a) of the monocrystalline layer (28). A front plate (12) is bonded to the outer surface (28a) of the monocrystalline layer (28), and the carrier (52) is removed. The central portion of the etch stop layer (30) is removed from the inner surface (28b) of the monocrystalline layer (28), and the exposed central portion (28c) of the layer (28) is uniformly thinned to approximately 400 angstroms using plasma assisted chemical etching. A back plate (14 ) having a back electrode (16) formed thereon is adhered to the unetched peripheral portion (28d) of the inner surface (28b) of the monocrystalline layer (28) to define a sealed space (24) between the front and back electrodes (12,14) which is filled with liquid crystal material (26). Large scale integrated driver circuitry (38,40) is fabricated in the peripheral portion (28d) of the layer (28) laterally external of the back plate (14) and externally interconnected by via holes (28g,28h) and wirebonds (44,45).

Claims13

Dependent claims

A livid crystal display comprising:

transparent first plate having an inner surface and an outer surface;
a monocrystalline semiconductor layer having an inner surface and an outer surface, said outer surface of the semiconductor layer being transparently adhered to said inner surface of the first plate;
a transparent first electrode which is adhered to said inner surface of the first plate;
a microelectronic driver device which is formed on said outer surface of the semiconductor layer and operatively connected to the first electrode;
a second plate having an inner surface and an outer surface;
a second electrode formed on said inner surface of the second plate;
spacer means for spacing said inner surfaces of the first and second plates from each other by a predetermining spacing;
sealing means for providing a peripheral seal around the first and second plates to define a sealed space between the first and second electrodes;
and
a liquid crystal material provided in said space;
said spacer means and sealing means in combination comprising a continuous peripheral protrusion which extends from said inner surface of the semiconductor layer toward said inner surface of the second plate and has a height corresponding to said predetermined spacing.

8 more elements

A liquid crystal display comprising:

transparent first and second plates having inner and outer surfaces, said first plate laterally external of the second plate and has an inner surface;
a monocrystalline semiconductor layer having an inner surface and an outer surface, said outer surface of the semiconductor layer being transparently adhered to said inner surface of the first plate, said semiconductor layer comprising a peripheral portion having an outer surface which is transparently adhered to said inner surface of said peripheral portion of the first plate;
a transparent first electrode which is adhered to said inner surface of the first plate;
a microelectronic driver device which is formed on said outer surface of the semiconductor layer and operatively connected to the first electrode;
a second electrode formed on said inner surface of the second plate;
microelectronic circuit means for controlling said driver device, the circuit means being formed on said outer surface of said peripheral portion of the semiconductor layer;
spacer means for spacing said inner surfaces of the first and second plates from each other by a predetermined spacing;
sealing means for providing a peripheral seal around the first and second plates to define a sealed space between the first and second electrodes;
and
a liquid crystal material provided in said space.

7 more elements

Dependencies are inferred from the claim text.

Liquid crystal display including electrodes and driver devices integrally formed in monocrystalline semiconductor layer

Life of this patent

Liquid crystal display including electrodes and driver devices integrally formed in monocrystalline semiconductor layer

Life of this patent

Abstract

Claims13