Power semiconductor devices integrated with clamp diodes having separated gate metal pads to avoid breakdown voltage degradation

• US 8,378,411 B2
• Filed: 03/24/2011
• Issued: 02/19/2013
• Est. Priority Date: 05/18/2009
• Status: Active Grant

• Current Assignee: Force Technology
• Original Assignee: Force Technology
• Inventors: Hsieh, Fu-Yuan
• Primary Examiner(s): Doan, Theresa T
• Application Number:
  US13/070,755
• Publication Number:
  US 20110180844A1
• Time in Patent Office: 698 Days
• Field of Search: 257327-328, 257/140, 257/334, 257341-343, 257/E27.016, 257/E27.013, 257/E29.199, 438/268, 438/270
• US Class Current: 257/327
• CPC Class Codes: H01L 2224/04042 Bonding areas specifically adapted for wire connectors, e.g. wirebond pads
• CPC Class Codes: H01L 2224/05 of an individual bonding area
• CPC Class Codes: H01L 2224/05552 in top view
• CPC Class Codes: H01L 2224/0603 Bonding areas having different sizes, e.g. different heights or widths
• CPC Class Codes: H01L 2224/06051 Bonding areas having different shapes
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/4813 Connecting within a semiconductor or solid-state body, i.e. fly wire, bridge wire
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49111 the connectors connecting two common bonding areas, e.g. Litz or braid wires
• CPC Class Codes: H01L 2224/49113 the connectors connecting different bonding areas on the semiconductor or solid-state body to a common bonding area outside the body, e.g. converging wires
• CPC Class Codes: H01L 2224/4917 Crossed wires
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 24/05 of an individual bonding area
• CPC Class Codes: H01L 24/06 of a plurality of bonding areas
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• CPC Class Codes: H01L 27/0255 using diodes as protective elements
• CPC Class Codes: H01L 27/0629 : in combination with diodes, or resistors, or capacitors
• 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 29/0696 : 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 29/1095 : Body region, i.e. base region, of DMOS transistors or IGBTs cell layout H01L29/0696
• CPC Class Codes: H01L 29/402 : Field plates
• CPC Class Codes: H01L 29/407 : Recessed field plates, e.g. trench field plates, buried field plates
• CPC Class Codes: H01L 29/41766 : with at least part of the source or drain electrode having contact below the semiconductor surface, e.g. the source or drain electrode formed at least partially in a groove or with inclusions of conductor inside the semiconductor H01L29/41733 - H01L29/41758 take precedence
• CPC Class Codes: H01L 29/42372 : characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out H01L29/42324 takes precedence
• CPC Class Codes: H01L 29/4238 : characterised by the surface lay-out
• CPC Class Codes: H01L 29/456 : on silicon
• CPC Class Codes: H01L 29/7397 : and a gate structure lying on a slanted or vertical surface or formed in a groove, e.g. trench gate IGBT
• CPC Class Codes: H01L 29/7809 : having both source and drain contacts on the same surface, i.e. Up-Drain VDMOS transistors
• CPC Class Codes: H01L 29/7811 : with an edge termination structure guard regions per se H01L29/0619; field plates per se H01L29/402
• 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 29/7821 : the other device being a breakdown diode, e.g. Zener diode
• CPC Class Codes: H01L 29/866 : Zener diodes
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/12035 : Zener diode
• CPC Class Codes: H01L 2924/1305 : Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 : Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/19043 : being a resistor

Abstract

A structure of power semiconductor device integrated with clamp diodes having separated gate metal pads is disclosed. The separated gate metal pads are wire bonded together on the gate lead frame. This improved structure can prevent the degradation of breakdown voltage due to electric field in termination region blocked by polysilicon or gate metal.

Claims

1. A semiconductor power device comprising:

a source region of a first conductivity type;

a body region of a second conductivity type encompassing said source region;

a first drain region of said first conductivity type disposed outside of edge termination;

a gate separated by an insulating layer from channel region of said body region;

a source metal layer connected to said source regions and said body regions;

a first gate metal connected to said gate;

a first drain metal connected to said first drain region;

said source region, said body region, said gate and said first drain region formed in a top side of semiconductor chip;

a gate-drain clamp diode connected between a second gate metal on the gate-drain clamp diode and said first drain metal, composed of multiple back-to-back polysilicon Zener diodes disposed outside of edge termination area without having said polysilicon Zener diode or said second gate metal cross over said edge termination;

a second drain region formed on a bottom side of said semiconductor chip;

a second drain metal layer connected to said second drain region; and

said first and second gate metals connected together at a gate lead frame through at least one bonding wire.

2. The semiconductor power device of claim 1 is a trench IGBT wherein:

said gate is a trenched gate;

said source region is an emitter region of said first conductivity type;

said body region is a base region of said second conductivity type;

said first drain region is a first collector region of said first conductivity type;

said source metal is a emitter metal;

said first drain metal is a first collector metal; and

said gate-drain clamp diode is a gate-collector clamp diode.

3. The semiconductor power device of claim 2 further comprises an on-resistance reduction implantation region having same conductivity type as said emitter region surrounding trench bottom of each said trenched gate.

4. The semiconductor power device of claim 2 is a PT trench IGBT further comprising:

a heavily doped substrate of said second conductivity type;

a first epitaxial layer of said first conductivity type grown on said substrate;

a second epitaxial layer of said first conductivity type grown on said first epitaxial layer, having less doping concentration than said first epitaxial layer; and

a second collector region of said second conductivity type is disposed on said bottom side of said substrate.

5. The semiconductor power device of claim 2 is a NPT trench IGBT further comprising:

a lightly doped substrate of said first conductivity type; and

a second collector region of said second conductivity type is disposed on the bottom side of said lightly doped substrate.

6. The semiconductor power device of claim 2 is a NPT trench IGBT further comprising:

a lightly doped substrate of said first conductivity type; and

a second collector region comprising alternately heavily doped regions with said first and second type conductivity formed on the bottom side of said lightly doped substrate.