Low turn-on voltage inp schottky device and method
AssigneeHRL Laboratories, LLC
InventorsADELE E. SCHMITZ, ROBERT H. WALDEN, MARK LUI, MARK K. YU
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Abstract
A Schottky diode, and a method of making the same, which is fabricated on InP material and a Schottky layer including InxAl1-xAs with x>0.6, or else including a chirped graded superlattice in which successive periods of the superlattice contain progressively less GaInAs and progressively more AlInAs, the increase in AlInAs being terminated before the proportion of AlInAs within the last period (adjacent the anode metal) exceeds 80%. Such fabrication creates an InP-based Schottky diode having a low turn-on voltage which may be predictably set within a range by adjusting the fabrication parameters.
Claims20
A Schottky diode comprising a cathode contact layer and a semiconductor Schottky layer adjacent a Schottky anode metallization,
- wherein said Schottky layer is a superlattice having a plurality of layer periods from a first layer period nearest the cathode contact layer to a last layer period nearest the anode metallization, each layer period having a thickness and including a first sublayer of GaInAs having a thickness and a second sublayer of AlinAs having a thickness, and each layer period having a proportion of GaInAs to AlInAs;
- and
- wherein the thickness of the first and second sublayers is varied between adjacent layer periods such that the proportion of GaInAs to AlInAs varies stepwise between adjacent layer periods, and
- the thickness of AlInAs in said last layer period is less than 80% of the thickness of said last layer period.
A Schottky diode comprising:
- an InP substrate;
- a Schottky anode metallization;
- and
- a semicondoctor Schottky layer adjacent the Schottky anode metallization, wherein said Schottky layer is predominantly InxAl1-xAs with x greater than 0.6.
A method of making a Schottky diode comprising steps of:
- preparing an InP substrate;
- growing a doped cathode contact layer of GaInAs above the substrate;
- growing a semiconductor Schottky layer above the cathode contact layer, the Schottky layer being either:
- (a) a truncated chirped superlattice of GaInAs and AlIAs, or
- (b) predominantly InxAl1-xAs with x greater than 0.6;
- and depositing a metal anode contact of the Schottky layer.
Dependencies are inferred from the claim text.