FIELD PLATE TRENCH TRANSISTOR AND METHOD FOR PRODUCING IT

• US 20110095362A1
• Filed: 01/04/2011
• Published: 04/28/2011
• Est. Priority Date: 08/31/2005
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Meyer, Thorsten, Hirler, Franz, Pfirsch, Frank, Klein, Wolfgang, Rieger, Walter
• Granted Patent: US 8,334,564 B2
• Time in Patent Office: Days
• US Class Current: 257/334
• CPC Class Codes: H01L 27/04 the substrate being a semiconductor body
• CPC Class Codes: H01L 27/0727 in combination with diodes, or capacitors or resistors
• CPC Class Codes: H01L 29/0696 of cellular field-effect devices, e.g. multicellular DMOS transistors or IGBTs
• CPC Class Codes: H01L 29/0878 Impurity concentration or distribution
• CPC Class Codes: H01L 29/404 Multiple field plate structures
• CPC Class Codes: H01L 29/407 Recessed field plates, e.g. trench field plates, buried field plates
• CPC Class Codes: H01L 29/42368 the thickness being non-uniform
• CPC Class Codes: H01L 29/66734 with a step of recessing the gate electrode, e.g. to form a trench gate electrode
• CPC Class Codes: H01L 29/732 Vertical transistors
• CPC Class Codes: H01L 29/735 Lateral transistors
• CPC Class Codes: H01L 29/7803 structurally associated with at least one other device assemblies H01L25/00; integrated circuits H01L27/00
• CPC Class Codes: H01L 29/7808 the other device being a breakdown diode, e.g. Zener diode
• CPC Class Codes: H01L 29/7813 with trench gate electrode, e.g. UMOS transistors trench gate electrodes per se H01L29/4236
• CPC Class Codes: H01L 29/861 Diodes

Abstract

A field plate trench transistor having a semiconductor body. In one embodiment the semiconductor has a trench structure and an electrode structure embedded in the trench structure. The electrode structure being electrically insulated from the semiconductor body by an insulation structure and having a gate electrode structure and a field electrode structure. The field plate trench transistor has a voltage divider configured such that the field electrode structure is set to a potential lying between source and drain potentials.

Claims

1. A field plate trench transistor having a semiconductor body comprising:

a trench structure;

an electrode structure embedded in the trench structure, the electrode structure being electrically insulated from the semiconductor body by an insulation structure and having a gate electrode structure and a field electrode structure arranged below and/or alongside the gate electrode structure and electrically insulated from the latter; and

a voltage divider which is integrated into the field electrode structure or provided within the mesa zones (adjoining trenches containing field plates), the voltage divider being configured such that the field electrode structure is set to a potential lying between source and drain potentials and/or gate and drain potentials,

wherein the voltage divider is realized as a series circuit comprising at least one resistor and at least one diode which is forward-biased with respect to the drain potential or as a series circuit comprising a plurality of diodes which are forward-biased with respect to the source potential, which are connected between source and drain potentials.

2. The field plate trench transistor as claimed in claim 1, wherein the at least one diode is a zener diode.