Abstract: A light emitting device that achieves long life, and which is capable of performing high duty drive, by suppressing initial light emitting element deterioration is provided. Reverse bias application to an EL element (109) is performed one row at a time by forming a reverse bias electric power source line (112) and a reverse bias TFT (108). Reverse bias application can therefore be performed in synchronous with operations for write-in of an image signal, light emission, erasure, and the like. Reverse bias application therefore becomes possible while maintaining a duty equivalent to that of a conventional driving method.

Abstract: Semiconductor elements deteriorate or are destroyed due to electrostatic discharge damage. The present invention provides a semiconductor device in which a protecting means is formed in each pixel. The protecting means is provided with one or a plurality of elements selected from the group consisting of resistor elements, capacitor elements, and rectifying elements. Sudden changes in the electric potential of a source electrode or a drain electrode of a transistor due to electric charge that builds up in a pixel electrode is relieved by disposing the protecting means between the pixel electrode of the light-emitting element and the source electrode or the drain electrode of the transistor. Deterioration or destruction of the semiconductor element due to electrostatic discharge damage is thus prevented.

Abstract: A light emitting device capable of suppressing drop in luminance or luminance unevenness of a light emitting element due to deterioration of an electro luminescent material and capable of switching an image direction vertically to horizontally without a frame memory additionally provided. The light emitting device of the invention comprises in each pixel first to fourth transistors, a light emitting element, and a signal line. The first transistor and the second transistor control the connection between the signal line and a gate of the third transistor, the fourth transistor controls a current value supplied to the light emitting element, and the third transistor selects whether the current is supplied to the light emitting element or not. Further, the first transistor and the second transistor are switched separately.

Abstract: A display device having a first pixel electrode and a second pixel electrode whose areas are different from each other is provided. In the display device, the first pixel electrode and the second pixel electrode are electrically connected to a first transistor and a second transistor, respectively. Gates of the first transistor and the second transistor are electrically connected to each other. A potential is supplied to the first pixel electrode and the second pixel electrode through a wiring electrically connected to the first transistor and the second transistor.

Abstract: It is an object of the present invention to provide a display device preventing the external invasion of water and/or oxygen and preventing the deterioration of a luminous element due to these invading substances and to provide a production method including simple production steps for producing the display device. The invention provides a display device having a sealing material on the rim of an exposed interlayer insulator for preventing the invasion of water and/or oxygen from the interlayer insulator. Further, the invention provides a display device having a barrier body on an exposed interlayer insulator for preventing the invasion of water and/or oxygen from the interlayer insulator. Furthermore, the application of droplet discharge technique in production steps for producing the display device can eliminate a photolithography step such as exposing and developing. Thus, a method of producing a display device having an improved yield is provided.

Abstract: The present invention provides a method for manufacturing a highly reliable display device at a low cost with high yield. According to the present invention, a step due to an opening in a contact is covered with an insulating layer to reduce the step, and is processed into a gentle shape. A wiring or the like is formed to be in contact with the insulating layer and thus the coverage of the wiring or the like is enhanced. In addition, deterioration of a light-emitting element due to contaminants such as water can be prevented by sealing a layer including an organic material that has water permeability in a display device with a sealing material. Since the sealing material is formed in a portion of a driver circuit region in the display device, the frame margin of the display device can be narrowed.

Abstract: It is an object of the present invention to provide a display device preventing the external invasion of water and/or oxygen and preventing the deterioration of a luminous element due to these invading substances and to provide a production method including simple production steps for producing the display device. The invention provides a display device having a sealing material on the rim of an exposed interlayer insulator for preventing the invasion of water and/or oxygen from the interlayer insulator. Further, the invention provides a display device having a barrier body on an exposed interlayer insulator for preventing the invasion of water and/or oxygen from the interlayer insulator. Furthermore, the application of droplet discharge technique in production steps for producing the display device can eliminate a photolithography step such as exposing and developing. Thus, a method of producing a display device having an improved yield is provided.

Abstract: A light emitting device and an element substrate which are capable of suppressing variations in the luminance intensity of a light emitting element among pixels due to characteristic variations of a driving transistor without suppressing off-current of a switching transistor low and increasing storage capacity of a capacitor. According to the invention, a depletion mode transistor is used as a driving transistor. The gate of the driving transistor is fixed in its potential or connected to the source or drain thereof to operate in a saturation region with a constant current flow. A current controlling transistor which operates in a linear region is connected in series to the driving transistor, and a video signal for transmitting a light emission or non-emission of a pixel is inputted to the gate of the current controlling transistor through a switching transistor.

Abstract: The present invention provides a method for manufacturing a highly reliable display device at a low cost with high yield. According to the present invention, a step due to an opening in a contact is covered with an insulating layer to reduce the step, and is processed into a gentle shape. A wiring or the like is formed to be in contact with the insulating layer and thus the coverage of the wiring or the like is enhanced. In addition, deterioration of a light-emitting element due to contaminants such as water can be prevented by sealing a layer including an organic material that has water permeability in a display device with a sealing material. Since the sealing material is formed in a portion of a driver circuit region in the display device, the frame margin of the display device can be narrowed.

Abstract: An object of the present invention is to provide such a sealing structure that a material to be a deterioration factor such as water or oxygen is prevented from entering from external and sufficient reliability is obtained in a display using an organic or inorganic electroluminescent element. In view of the above object, focusing on permeability of an interlayer insulating film, deterioration of an electroluminescent element is suppressed and sufficient reliability is obtained by preventing water entry from an interlayer insulating film according to the present invention.

Abstract: The present invention provides a method for manufacturing a highly reliable display device at a low cost with high yield. According to the present invention, a step due to an opening in a contact is covered with an insulating layer to reduce the step, and is processed into a gentle shape. A wiring or the like is formed to be in contact with the insulating layer and thus the coverage of the wiring or the like is enhanced. In addition, deterioration of a light-emitting element due to contaminants such as water can be prevented by sealing a layer including an organic material that has water permeability in a display device with a sealing material. Since the sealing material is formed in a portion of a driver circuit region in the display device, the frame margin of the display device can be narrowed.

Abstract: A light emitting device and an element substrate which are capable of suppressing variations in the luminance intensity of a light emitting element among pixels due to characteristic variations of a driving transistor without suppressing off-current of a switching transistor low and increasing storage capacity of a capacitor. According to the invention, a depletion mode transistor is used as a driving transistor. The gate of the driving transistor is fixed in its potential or connected to the source or drain thereof to operate in a saturation region with a constant current flow. A current controlling transistor which operates in a linear region is connected in series to the driving transistor, and a video signal for transmitting a light emission or non-emission of a pixel is inputted to the gate of the current controlling transistor through a switching transistor.

Abstract: When a thin film transistor has an LDD structure or a double gate structure, the number of manufacturing steps increases, which may decrease the yield. The invention provides a display device where the influence of off current is reduced by a method different from the conventional one. According to the invention, a pass element is provided at one electrode of a light emitting element so as not to flow the off current of a transistor for driving the light emitting element through the light emitting element in a non-lighting period. The pass element allows the off current to flow outside, that is, the off current can be bypassed outside through the pass element.

Abstract: A potential of a gate of a driving transistor is fixed, and the driving transistor is operated in a saturation region, so that a current is supplied thereto anytime. A current control transistor operating in a linear region is disposed serially with the driving transistor, and a video signal for transmitting a signal of emission or non-emission of the pixel is input to a gate of the current control transistor via a switching transistor.

Abstract: A light emitting device that achieves long life, and which is capable of performing high duty drive, by suppressing initial light emitting element deterioration is provided. Reverse bias application to an EL element (109) is performed one row at a time by forming a reverse bias electric power source line (112) and a reverse bias TFT (108). Reverse bias application can therefore be performed in synchronous with operations for write-in of an image signal, light emission, erasure, and the like. Reverse bias application therefore becomes possible while maintaining a duty equivalent to that of a conventional driving method.

Abstract: The present invention provides a TFT that has a channel length particularly longer than that of an existing one, specifically, several tens to several hundreds times longer than that of the existing one, and thereby allowing turning to an on-state at a gate voltage particularly higher than the existing one and driving, and allowing having a low channel conductance gd. According to the present invention, not only the simple dispersion of on-current but also the normalized dispersion thereof can be reduced, and other than the reduction of the dispersion between the individual TFTs, the dispersion of the OLEDs themselves and the dispersion due to the deterioration of the OLED can be reduced.

Abstract: It is an object of the present invention to provide a display device preventing the external invasion of water and/or oxygen and preventing the deterioration of a luminous element due to these invading substances and to provide a production method including simple production steps for producing the display device. The invention provides a display device having a sealing material on the rim of an exposed interlayer insulator for preventing the invasion of water and/or oxygen from the interlayer insulator. Further, the invention provides a display device having a barrier body on an exposed interlayer insulator for preventing the invasion of water and/or oxygen from the interlayer insulator. Furthermore, the application of droplet discharge technique in production steps for producing the display device can eliminate a photolithography step such as exposing and developing. Thus, a method of producing a display device having an improved yield is provided.

Abstract: An object of the present invention is to provide such a sealing structure that a material to be a deterioration factor such as water or oxygen is prevented from entering from external and sufficient reliability is obtained in a display using an organic or inorganic electroluminescent element. In view of the above object, focusing on permeability of an interlayer insulating film, deterioration of an electroluminescent element is suppressed and sufficient reliability is obtained by preventing water entry from an interlayer insulating film according to the present invention.

Abstract: A-light-emitting device which realizes a high aperture ratio and in which the quality of image is little affected by the variation in the characteristics of TFTs. A large holding capacitor Cs is not provided in the pixel portion but, instead, the channel length and the channel width of the driving TFTs are increased, and the channel capacitance is utilized as Cs. The channel length is selected to be very larger than the channel width to improve current characteristics in the saturated region, and a high VGS is applied to the driving TFTs to obtain a desired drain current. Therefore, the drain currents of the driving TFTs are little affected by the variation in the threshold voltage. In laying out the pixels, further, wiring is arranged under the partitioning wall and the driving TFTs are arranged under the wiring in order to avoid a decrease in the aperture ratio despite of an increase in the size of the driving TFT.

Abstract: The data latch circuit of the invention includes a means for short-circuiting an input terminal and an output terminal of an inverter and by connecting the input terminal to one electrode of a capacitor and sampling a data signal or a reference potential to the other electrode of the capacitor, an accurate operation can be obtained without being influenced by variations in the TFT characteristics even when the amplitude of an input signal is small relatively to the width of a power supply voltage.