Liquid crystal display device with TFT ESD protective devices between I/O terminals or with a short circuited alignment film

A liquid crystal display device, comprising:

• a plurality of data signal lines;
• a plurality of scanning signal lines formed so as to cross said plurality of data signal lines;
• a picture element array wherein each picture element for displaying an image is formed so as to be surrounded by adjacent data signal lines and adjacent scanning signal lines;
• a first MOS transistor as a switching element for driving each picture element;
• a driving circuit for driving each picture element through each signal line and said first MOS transistor;
• a plurality of input-output terminals for inputting and outputting a signal in and from said driving circuit;
• a protective circuit connected across input-output terminals of said driving circuit, said protective circuit conducting when a potential difference of not less than a predetermined value is generated across the input-output terminals;
• and
• a common wiring composed of an electrically conductive member, formed in a vicinity of the input-output terminals of said driving circuit,
• wherein said plurality of data signal lines, said plurality of scanning signal lines, said picture element array, said first MOS transistor, said driving circuit, said plurality of input-output terminals, said protective circuit and said common wiring are monolithically formed on an insulating substrate, and
• said protective circuit includes a second MOS transistor which conducts when a potential difference of not less than the predetermined value is generated across the input-output terminals, said protective circuit being connected across the input-output terminals and said common wiring in such a manner that a gate insulating layer in contact with a gate electrode of said second MOS transistor is thicker than a gate insulating layer in contact with a gate electrode of said first MOS transistor.

A liquid crystal display device, comprising:

• a plurality of data signal lines;
• a plurality of scanning signal lines formed so as to cross said plurality of data signal lines;
• a picture element array wherein each picture element for displaying an image is formed so as to be surrounded by adjacent data signal lines and adjacent scanning signal lines;
• a transistor as a switching element for driving each picture element;
• a driving circuit for driving each picture element through each signal line and said transistor;
• a plurality of input-output terminals for inputting and outputting a signal in and from said driving circuit;
• a liquid crystal alignment film formed on each picture element, a surface of said liquid crystal alignment film being charged by a rubbing process;
• and
• a shorting member for shorting the surface of said liquid crystal alignment film and input-output terminals.

A liquid crystal display device, comprising:

• a plurality of data signal lines;
• a plurality of scanning signal lines;
• a picture element array wherein each picture element for displaying an image is formed so as to be surrounded by adjacent data signal lines and adjacent scanning signal lines;
• a plurality of transistors as switching elements, each transistor driving a corresponding picture element;
• a driving circuit for driving each picture element through each signal line and transistor, said driving circuit having a plurality of input-output terminals;
• and
• a plurality of protective circuits, each protective circuit being connected across corresponding adjacent input-output terminals of said driving circuit, each protective circuit including a transistor unit, wherein said transistor unit and said transistor have different threshold voltages.

A liquid crystal display device, comprising:

• a plurality of data signal lines;
• a plurality of scanning signal lines;
• a picture element array wherein each picture element for displaying an image is formed so as to be surrounded by adjacent data signal lines and adjacent scanning signal lines;
• a plurality of first transistors as switching elements, each first transistor driving a corresponding picture element;
• a driving circuit for driving each picture element through each signal line and first transistor, said driving circuit including a plurality of input-output terminals;
• a common wiring composed of an electrically conductive member, formed in a vicinity of said input-output terminals of said driving circuit;
• a first plurality of protective circuits, each protective circuit of said first plurality being connected across a corresponding input-output terminal of said driving circuit and said common wiring, each protective circuit of said first plurality including a second transistor, wherein said second transistor and said first transistor have different threshold voltages;
• and
• a second plurality of protective circuits, each protective circuit of said second plurality being connected across corresponding adjacent input-output terminals of said driving circuit, each protective circuit of said second plurality including a third transistor, wherein said third transistor and said first transistor have different threshold voltages.

A method of manufacturing a liquid crystal display device having a plurality of picture elements comprising:

• forming a liquid crystal alignment film on each picture element of the liquid crystal display device;
• charging a surface of said liquid crystal alignment film via a rubbing process;
• and
• shorting said surface and input-output terminals of a driving circuit for driving said plurality of picture elements, thereby reducing a potential difference between said surface and said input-output terminals.