HEMT semiconductor component with field plates

• US 8,866,191 B2
• Filed: 02/21/2008
• Issued: 10/21/2014
• Est. Priority Date: 02/22/2007
• Status: Active Grant

• Current Assignee: Ferdinand-Braun-Institut Ggmbh Leibniz-Institut Fur Hochstfrequenztechnik
• Original Assignee: Forschungsverbund Berlin E.V.
• Inventors: Bahat-Treidel, Eldat, Sidorov, Victor, Wuerfl, Joachim
• Primary Examiner(s): Jackson, Jr., Jerome
• Assistant Examiner(s): BUDD, PAUL A
• Application Number:
  US12/449,700
• Publication Number:
  US 20110221011A1
• Time in Patent Office: 2,434 Days
• Field of Search: 257/194, 257/195, 257/487, 257/488, 257/E29.246, 257/E29.247, 257/192
• US Class Current: 257/192
• CPC Class Codes: H01L 29/0619 with a supplementary region doped oppositely to or in rectifying contact with the semiconductor containing or contacting region, e.g. guard rings with PN or Schottky junction
• CPC Class Codes: H01L 29/2003 Nitride compounds
• CPC Class Codes: H01L 29/404 Multiple field plate structures
• CPC Class Codes: H01L 29/42316 for field-effect transistors
• CPC Class Codes: H01L 29/47 Schottky barrier electrodes H01L29/435 takes precedence
• CPC Class Codes: H01L 29/66462 with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT
• CPC Class Codes: H01L 29/66871 Processes wherein the final gate is made after the formation of the source and drain regions in the active layer, e.g. dummy-gate processes
• CPC Class Codes: H01L 29/7786 with direct single heterostructure, i.e. with wide bandgap layer formed on top of active layer, e.g. direct single heterostructure MIS-like HEMT
• CPC Class Codes: H01L 29/812 with a Schottky gate H01L29/7725, H01L29/775, H01L29/778, H01L29/806 take precedence; with Schottky contact on top of heterojunction gate H01L29/802

Abstract

A transistor in which the electric field is reduced in critical areas using field plates, permitting the electric field to be more uniformly distributed along the component, is provided, wherein the electric field in the active region is smoothed and field peaks are reduced. The semiconductor component has a substrate with an active layer structure, a source contact and a drain contact located on said active layer structure. The source contact and the drain contact are mutually spaced and at least one part of a gate contact is provided on the active layer structure in the region between the source contact and the drain contact, a gate field plate being electrically connected to the gate contact. In addition, at least two separate field plates are placed directly on the active layer structure or directly on a passivation layer.

Claims

1. A semiconductor component, comprising:

a substrate with an active layer structure disposed thereon, comprising at least one layer made of a semiconducting material, a source contact and a drain contact being disposed on the active layer structure and the source contact and the drain contact being spaced apart from each other,

a gate contact, at least a part of the gate contact being disposed on the active layer structure in an area between the source contact and the drain contact,

a gate field plate electrically connected to a gate electric potential of the gate contact and disposed directly on a passivation layer disposed on the active layer structure, and

at least two separate field plates of which at least one separate field plate is disposed directly on the active layer structure, wherein the passivation layer is patterned accordingly.

2. The semiconductor component according to claim 1,

wherein the at least one separate field plate is at least one of at least two field plates formed in a stripe shape and parallel to each other.

3. The semiconductor component according to one of claims 1 and 2, wherein

the active layer structure has a first layer made of a first semiconducting material and a second layer made of a second semiconducting material, and the band gap of the first semiconducting material is different from the band gap of the second semiconducting material and/or the spontaneous or piezoelectric polarization of the first semiconducting material is different from the spontaneous or piezoelectric polarization of the second semiconducting material, and the first semiconducting material and the second semiconducting material are chosen such that a two-dimensional electron gas forms in a boundary layer between the first layer and the second layer.

4. The semiconductor component according to one of claims 1 and 2, wherein

the at least one other separate field plate of the at least two separate field plates is connected to the drain potential or is connected to the source potential.

5. The semiconductor component according to one of claims 1 and 2, wherein

the at least one separate field plate is disposed unearthed directly on the active layer structure.

6. The semiconductor component according to one of claims 1 and 2, wherein

the gate field plate and the at least one separate field plate are coated with a protective film.