High electron mobility device with intrinsic AlAs/GaAs superlattice separator region

Claim 2

A field effect semiconductor device in which a two-dimensional electron gas is utilized comprising: a semi-insulating GaAs substrate; an intrinsic-type GaAs active layer formed on said substrate; a superlattice structure layer comprising: a first intrinsic-type AlAs thin layer formed on said active layer; a GaAs thin well layer formed on said first intrinsic-type AlAs thin layer and including: a first undoped GaAs layer formed on said first intrinsic-type AlAs thin layer; a second undoped GaAs layer; and an atomic plane of dopant atoms formed between said first and said second undoped GaAs layers; a second intrinsic-type AlAs thin layer formed on said GaAs thin well layer, forming a quantum well; a doped AlGaAs layer formed on said superlattice structure layer; and electrodes for source drain and gate formed on said quantum well.

Claim 3

A semiconductor device according to claim 1, wherein said superlattice structure layer further comprises a multi-quantum well structure in which intrinsic-type AlGa thin layers and GaAs thin well layers are alternately formed, and wherein at least one of said well layers is doped with an atomic plane of dopant atoms.

Claim 4

A field effect semiconductor device in which is a two-dimensional electron gas is utilized comprising: a semi-insulating GaAs substrate; an intrinsic-type GaAs active layer formed on said substrate; a superlattice structure layer comprising: a first intrinsic-type AlAs thin layer formed on said active layer; a GaAs thin well layer formed on said first AlAs thin layer and including: a first undoped GaAs layer formed on said first intrinsic-type thin layer; a second undoped GaAs layer; and an atomic plane of dopant atoms formed between said first and said second undoped GaAs layers; and a second intrinsic-type AlAs thin layer formed on said doped GaAs thin layer, forming a GaAs quantum well; an n-type Al x Ga l-x As layer formed on said superlattice structure layer, where x is 0.2; electrodes for source, drain and gate formed over said n-type Al x Ga l-x As layer.

Claim 5

A field effect semiconductor device in which is a two-dimensional electron gas is utilized comprising: a semi-insulating GaAs substrate; an intrinsic-type GaAs active layer formed on said substrate; a superlattice structure layer comprising: a first intrinsic-type AlAs thin layer formed on said active layer; a GaAs thin well layer formed on said first AlAs thin layer and including: a first undoped GaAs layer formed on said first intrinsic-type thin layer; a second undoped GaAs layer; and an atomic plane of dopant atoms formed between said first and said second undoped GaAs layers; and a second intrinsic-type AlAs thin layer formed on said doped GaAs thin layer, forming a GaAs quantum well; an n-type Al x Ga l-x As layer formed on said superlattice structure layer, where x is 0.2; electrodes for source, drain and gate formed over said n-type Al x Ga l-x As layer.

Claim 6

A field effect semiconductor device in which a two-dimensional electron gas is utilized, comprising: a semi-insulating InP substrate; an intrinsic-type InGaAs active layer formed on said substrate; a superlattice structure layer comprising: a first intrinsic-type InAlAs thin layer formed on said active layer; a InGaAs thin well layer formed on said first intrinsic-type InAIAs thin layer and including: a first undoped InGasAs layer formed on said first intrinsic-type InGaAs thin layer; a second undoped InGaAs layer; and an atomic plane of dopant atoms formed between said first and said second undoped InGasAs layers; a second intrinsic-type InAlAs thin layer formed on said InGasAs thin well layer, forming a quantum well; a doped INAIGaAs layer formed on said superlattice structure layer; and electrodes for source, drain and gate formed over said quantum well.

Claim 7

A field effect semiconductor device in which a two-dimensional electron gas is utilized, comprising: a semi-insulating InP substrate; an intrinsic-type InGaAs active layer formed on said substrate; a superlattice structure layer comprising: a first intrinsic-type InAlAs thin layer formed on said active layer; a InGaAs thin well layer formed on said first intrinsic-type InAIAs thin layer and including: a first undoped InGasAs layer formed on said first intrinsic-type InGaAs thin layer; a second undoped InGaAs layer; and an atomic plane of dopant atoms formed between said first and said second undoped InGasAs layers; a second intrinsic-type InAlAs thin layer formed on said InGasAs thin well layer, forming a quantum well; a doped INAIGaAs layer formed on said superlattice structure layer; and electrodes for source, drain and gate formed over said quantum well.

Claim 8

A semiconductor device according to claim 4, wherein said superlattice structure layer further comprises a multi-quantum well structure in which intrinsic-type INAlAs thin layers and InGasAs thin well layers are alternately formed, and wherein at least one of said thin well layers is doped with an atomic plane of dopant atoms.