Bipolar junction transistors including inorganic channels and organic emitter junctions are used in some applications for forming high resolution active matrix displays. Arrays of such bipolar junction transistors are electrically connected to thin film switching transistors and provide high drive currents for passive devices such as organic light emitting diodes.

An integrated radiation sensor for detecting the presence of an environmental material and/or condition includes a sensing structure and first and second lateral bipolar junction transistors (BJTs) having opposite polarities. The first lateral BJT has a base that is electrically coupled to the sensing structure and is configured to generate an output signal indicative of a change in stored charge in the sensing structure. The second lateral BJT is configured to amplify the output signal of the first bipolar junction transistor. The first and second lateral BJTs, the sensing structure, and the substrate on which they are formed comprise a monolithic structure.

A bipolar junction transistor includes an intrinsic base formed on a substrate. The intrinsic base includes a superlattice stack including a plurality of alternating layers of semiconductor material. A collector and emitter are formed adjacent to the intrinsic base on opposite sides of the base. An extrinsic base structure is formed on the intrinsic base.

A bipolar junction transistor includes an intrinsic base formed on a substrate. The intrinsic base includes a superlattice stack including a plurality of alternating layers of semiconductor material. A collector and emitter are formed adjacent to the intrinsic base on opposite sides of the base. An extrinsic base structure is formed on the intrinsic base.

An exemplary biosensor sensor for detecting the presence of a biological material includes an SOI substrate, a BJT formed on at least a portion of the substrate, and a sensing structure formed on at least a portion of an upper surface of the BJT. The BJT includes an emitter region, a collector region and a self-aligned epitaxially grown intrinsic base region laterally adjacent to the emitter and collector regions. The sensing structure includes an opening, centered above and exposing the intrinsic base region, and at least one dielectric layer formed in the opening and contacting at least a portion of the intrinsic base region. The dielectric layer is configured to respond to charges in biological molecules.

An exemplary biosensor sensor for detecting the presence of a biological material includes an SOI substrate, a BJT formed on at least a portion of the substrate, and a sensing structure formed on at least a portion of an upper surface of the BJT. The BJT includes an emitter region, a collector region and a self-aligned epitaxially grown intrinsic base region laterally adjacent to the emitter and collector regions. The sensing structure includes an opening, centered above and exposing the intrinsic base region, and at least one dielectric layer formed in the opening and contacting at least a portion of the intrinsic base region. The dielectric layer is configured to respond to charges in biological molecules.

A method of forming a semiconductor structure includes providing an emitter and a collector on a surface of an insulator layer. The emitter and the collector are spaced apart and have a doping of a first conductivity type. An intrinsic base is formed between the emitter and the collector and on the insulator layer by epitaxially growing the intrinsic base from at least a vertical surface of the emitter and a vertical surface of the collector. The intrinsic base has a doping of a second conductivity type opposite to the first conductivity type, and a first heterojunction exists between the emitter and the intrinsic base and a second heterojunction exists between the collector and the intrinsic base.

A bipolar junction transistor includes an intrinsic base formed on a substrate. The intrinsic base includes a superlattice stack including a plurality of alternating layers of semiconductor material. A collector and emitter are formed adjacent to the intrinsic base on opposite sides of the base. An extrinsic base structure is formed on the intrinsic base.

A bipolar junction transistor includes an intrinsic base formed on a substrate. The intrinsic base includes a superlattice stack including a plurality of alternating layers of semiconductor material. A collector and emitter are formed adjacent to the intrinsic base on opposite sides of the base. An extrinsic base structure is formed on the intrinsic base.

An integrated radiation sensor for detecting the presence of an environmental material and/or condition includes a sensing structure and first and second lateral bipolar junction transistors (BJTs) having opposite polarities. The first lateral BJT has a base that is electrically coupled to the sensing structure and is configured to generate an output signal indicative of a change in stored charge in the sensing structure. The second lateral BJT is configured to amplify the output signal of the first bipolar junction transistor. The first and second lateral BJTs, the sensing structure, and the substrate on which they are formed comprise a monolithic structure.