摘要:
A base layer interposed between an n-type GaAs collector layer and an n-type AlGaAs emitter layer is composed of a p-type InAlGaAs. From a collector/base interface to an emitter/base interface, an InAs composition of the base layer is decreased and a concentration of carbon as a p-type impurity thereof is increased so as to obtain a built-in internal field intensity in the base layer by a cooperative effect of the graded-bandgap and the impurity concentration gradient, thus reducing a base transit time of electrons. The base layer is fabricated according to MOMBE using TMG as a gallium source, controlling the InAs composition, so that a desired carbon concentration gradient is automatically formed. Thereby, a high performance, heterojunction bipolar transistor with an increased built-in internal field intensity in the base layer is obtained.
摘要:
A base layer interposed between an n-type GaAs collector layer and an n-type AlGaAs emitter layer is composed of a p-type InAlGaAs. From a collector/base interface to an emitter/base interface, an InAs composition of the base layer is decreased and a concentration of carbon as a p-type impurity thereof is increased so as to obtain a built-in internal field intensity in the base layer by a cooperative effect of the graded-bandgap and the impurity concentration gradient, thus reducing a base transit time of electrons. The base layer is fabricated according to MOMBE using TMG as a gallium source, controlling the InAs composition, so that a desired carbon concentration gradient is automatically formed. Thereby, a high performance heterojunction bipolar transistor with an increased built-in internal field intensity in the base layer is obtained.
摘要:
A heterojunction bipolar transistor includes a first emitter region. A second emitter region extends on the first emitter region and is connected to the first emitter region via a junction. The second emitter region has a forbidden band gap wider than a forbidden band gap of the first emitter region. At the junction, the second emitter region has a carrier energy level substantially equal to a carrier energy level of the first emitter region. An intrinsic base region extends on the second emitter region and has a forbidden band gap narrower than the forbidden band gap of the second emitter region. A collector region extends on the intrinsic base region. An extrinsic base region extends outward of the intrinsic base region and contacts the intrinsic base region and the second emitter region. The extrinsic base region separates from the first emitter region. A portion of the extrinsic base region which adjoins the second emitter region has a forbidden band gap substantially equal to the forbidden band gap of the second emitter region. A high-resistivity region extends underneath the extrinsic base region.
摘要:
An insulating-gate semiconductor device has a first nitride semiconductor layer formed over a substrate and an insulating oxidation layer obtained by oxidizing a second nitride semiconductor layer formed on the first nitride semiconductor layer. A gate electrode is formed on the insulating oxidation layer.
摘要:
The semiconductor device of this invention includes an active region formed from a group III nitride semiconductor grown on a substrate and an insulating oxide film formed in a peripheral portion of the active region by oxidizing the group III nitride semiconductor. On the active region, a gate electrode in Schottky contact with the active region extending onto the insulating oxide film and having an extended portion on the insulating oxide film is formed, and ohmic electrodes respectively serving as a source electrode and a drain electrode are formed with space from side edges along the gate length direction of the gate electrode.
摘要:
The semiconductor device of this invention includes an active region formed from a group III nitride semiconductor grown on a substrate and an insulating oxide film formed in a peripheral portion of the active region by oxidizing the group III nitride semiconductor. On the active region, a gate electrode in Schottky contact with the active region extending onto the insulating oxide film and having an extended portion on the insulating oxide film is formed, and ohmic electrodes respectively serving as a source electrode and a drain electrode are formed with space from side edges along the gate length direction of the gate electrode.
摘要:
An insulating-gate semiconductor device has a first nitride semiconductor layer formed over a substrate and an insulating oxidation layer obtained by oxidizing a second nitride semiconductor layer formed on the first nitride semiconductor layer. A gate electrode is formed on the insulating oxidation layer.
摘要:
An n-type first single crystal silicon layer is provided as collector region over a silicon substrate with a first insulating film interposed therebetween. A p-type first polysilicon layer is provided as an extension of a base region over the first single crystal silicon layer with a second insulating film interposed therebetween. A p-type second single crystal silicon layer is provided as intrinsic base region on a side of the first single crystal silicon layer, second insulating film and first polysilicon layer. An n-type third single crystal silicon layer is provided as emitter region on a side of the second single crystal silicon layer. And an n-type third polysilicon layer is provided on the first insulating film as extension of an emitter region and is connected to a side of the third single crystal silicon layer.
摘要:
On a GaAs substrate are provided a buffer layer comprising an Undope-GaAs layer, a first n-InGaAs layer having an In composition ratio of 0.2, a second n-InGaAs layer having an In composition ratio of 0.02, a contact layer comprising an N.sup.+ type GaAs layer, a gate electrode, a source electrode, and a drain electrode. The first n-InGaAs layer and the second n-InGaAs layer form active layers in which an operating current flows. The second n-InGaAs layer having excellent crystallinity is formed on the first n-InGaAs layer. Consequently, a field effect transistor which displays a super low distortion characteristic having IP2 of 67.2 dBm and IP3 of 35 dBm can be manufactured with good reproducibility.
摘要:
A lateral bipolar transistor includes: a substrate; a first insulative region formed on the substrate; a first semiconductor region of a first conductivity type selectively formed on the first insulative region; a second insulative region formed so as to substantially cover the first semiconductor region; and a second semiconductor region of a second conductivity type different from the first conductivity type, a second semiconductor region being selectively formed, wherein: the second insulative region has a first opening which reaches a surface of the first semiconductor region, and the first semiconductor region has a second opening which reaches the underlying first insulative region, the second opening being provided in a position corresponding to the first opening of the second insulative region; the second semiconductor region is formed so as to fill the first opening and the second opening, thereby functioning as a base region; a lower portion of the second semiconductor region which at least fills the second opening is formed by lateral growth from a face of the first semiconductor region defining a side wall of the second opening; and the first semiconductor region includes an emitter region and a collector region formed therein.