An optoelectronic device and method of making the same. The device comprising: a substrate; an epitaxial crystalline cladding layer, on top of the substrate; and an optically active region, above the epitaxial crystalline cladding layer; wherein the epitaxial crystalline cladding layer has a refractive index which is less than a refractive index of the optically active region, such that the optical power of the optoelectronic device is confined to the optically active region.

An array substrate, a display panel and a display apparatus are provided. The array substrate includes: a base layer having an upper surface. A thin film transistor is provided in a first region on the upper surface. A photoelectric sensor is provided in a second region on the side of the base layer, which is configured for fingerprint identification. A passivation layer is provided on a side of both the thin film transistor and the photoelectric sensor away from the base layer.

Certain embodiments of the present invention may be directed to a transistor structure. The transistor structure may include a semiconductor substrate. The semiconductor substrate may include a drift region, a collector region, an emitter region, and a lightly-doped/undoped region. The lightly-doped/undoped region may be lightly-doped and/or undoped. The transistor structure may also include a heterostructure. The heterostructure forms a heterojunction with the lightly-doped/undoped region. The transistor structure may also include a collector terminal. The collector terminal is in contact with the collector region. The transistor structure may also include a gate terminal. The gate terminal is in contact with the heterostructure. The transistor structure may also include an emitter terminal. The emitter terminal is in contact with the lightly-doped/undoped region and the emitter region.

An improvement is achieved in the performance of a semiconductor device. A semiconductor device includes an n.sup.-type semiconductor region formed in a p-type well, an n-type semiconductor region formed closer to a main surface of a semiconductor substrate than the n.sup.-type semiconductor region, and a p.sup.-type semiconductor region formed between the n.sup.-type semiconductor region and the n-type semiconductor region. A net impurity concentration in the n.sup.-type semiconductor region is lower than a net impurity concentration in the n-type semiconductor region. A net impurity concentration in the p.sup.-type semiconductor region is lower than a net impurity concentration in the p-type well.