High Voltage Semiconductor Power Switching Device

• US 20160079237A1
• Filed: 11/23/2015
• Published: 03/17/2016
• Est. Priority Date: 10/28/2013
• Status: Active Grant

• Current Assignee: Mosway Semiconductor Limited
• Original Assignee: Mosway Semiconductor Limited
• Inventors: Chan, On-Bon Peter, Tang, Chi-keung, Tse, Chiu-Sing Celement
• Granted Patent: US 9,553,085 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 21/8249 Bipolar and MOS technology
• CPC Class Codes: H01L 21/84 the substrate being other than a semiconductor body, e.g. being an insulating body
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 23/535 including internal interconnections, e.g. cross-under constructions internal lead connections H01L23/481
• CPC Class Codes: H01L 27/0635 in combination with bipolar transistors and diodes, or resistors, or capacitors
• CPC Class Codes: H01L 27/0647 Bipolar transistors in combination with diodes, or capacitors, or resistors, e.g. vertical bipolar transistor and bipolar lateral transistor and resistor
• CPC Class Codes: H01L 27/0825 Combination of vertical direct transistors of the same conductivity type having different characteristics,(e.g. Darlington transistors)
• CPC Class Codes: H01L 27/1203 the substrate comprising an insulating body on a semiconductor body, e.g. SOI three-dimensional layout H01L27/0688
• CPC Class Codes: H01L 29/0634 Multiple reduced surface field (multi-RESURF) structures, e.g. double RESURF, charge compensation, cool, superjunction (SJ), 3D-RESURF, composite buffer (CB) structures
• CPC Class Codes: H01L 29/0804 Emitter regions of bipolar transistors
• CPC Class Codes: H01L 29/0821 Collector regions of bipolar transistors
• CPC Class Codes: H01L 29/0847 of field-effect transistors with insulated gate H01L29/0653 takes precedence; with a passive supplementary region between source or drain and substrate related to punch-through, capacity or isolation phenomena H01L29/1079; with LDD or DDD structure H01L29/7833; for thin film transistors H01L29/78618
• CPC Class Codes: H01L 29/1004 Base region of bipolar transistors
• 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 29/41708 Emitter or collector electrodes for bipolar transistors
• CPC Class Codes: H01L 29/41758 for lateral devices with structured layout for source or drain region, i.e. the source or drain region having cellular, interdigitated or ring structure or being curved or angular H01L29/41733 - H01L29/4175 take precedence
• CPC Class Codes: H01L 29/42304 Base electrodes for bipolar transistors
• CPC Class Codes: H01L 29/42356 : Disposition, e.g. buried gate electrode H01L29/42324 and H01L29/4234 take precedence
• CPC Class Codes: H01L 29/42364 : characterised by the insulating layer, e.g. thickness or uniformity H01L29/42324 and H01L29/4234 take precedence
• CPC Class Codes: H01L 29/45 : Ohmic electrodes
• CPC Class Codes: H01L 29/4916 : the conductor material next to the insulator being a silicon layer, e.g. polysilicon doped with boron, phosphorus or nitrogen H01L29/4908, H01L29/4983 take precedence
• CPC Class Codes: H01L 29/872 : Schottky 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 2924/13055 : Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]

Abstract

A three terminal high voltage Darlington bipolar transistor power switching device includes two high voltage bipolar transistors, with collectors connected together serving as the collector terminal. The base of the first high voltage bipolar transistor serves as the base terminal. The emitter of the first high voltage bipolar transistor connects to the base of the second high voltage bipolar transistor (inner base), and the emitter of the second high voltage bipolar transistor serves as the emitter terminal. A diode has its anode connected to the inner base (emitter of the first high voltage bipolar transistor, or base of the second high voltage bipolar transistor), and its cathode connected to the base terminal. Similarly, a three terminal hybrid MOSFET/bipolar high voltage switching device can be formed by replacing the first high voltage bipolar transistor of the previous switching device by a high voltage MOSFET.

Claims

1. A method of fabricating a three terminal high voltage Darlington bipolar power switching device having a connector terminal, a base terminal with a base pin, and an emitter terminal with an emitter pin and including the steps of:

conductive die attaching first and second high voltage bipolar transistors each having a substrate as a collector terminal to a main die pad of a three pin power device package in which the main die pad is also electrically connected to the collector terminal of the switching device;

conductive die attaching a diode having a cathode and an anode with the cathode as a substrate to the base bonding pin of the base terminal of the three pin power device package;

bonding the base of the first high voltage bipolar transistor to the base terminal of the three pin power device package;

inter-chip bonding of the emitter of the first high voltage bipolar transistor to the base of the second high voltage bipolar transistor;

bonding of the emitter of the first high voltage bipolar transistor and/or the base of the second high voltage bipolar transistor to the anode of the diode;

bonding of the emitter of the second high voltage bipolar transistor to the emitter pin of the three pin power package; and

subsequent standard moulding and follow on process to complete a device packaging.

2. The method of claim 1, wherein the diode is a Schottky diode.

3. A method of fabricating a three terminal high voltage Darlington bipolar power switching device having a connector terminal, a base terminal having a base bonding pin and an emitter terminal with an emitter pin including the steps of:

conductive die attaching a single semiconductor chip high voltage Darlington bipolar transistor having a collector, a first base, an inner base, and an emitter, with a substrate as the collector terminal, to a main die pad of a three pin power device package in which the main die pad is also electrically connected to the collector terminal of the switching device;

conductive die attaching a diode having a cathode and an anode with the cathode as a substrate to the base bonding pin of the base terminal of the three pin power device package;

bonding the first base of the high voltage Darlington bipolar transistor to the base terminal of the three pin power device package;

bonding the base of the high voltage Darlington bipolar transistor to the anode of the diode;

bonding the emitter of the high voltage Darlington bipolar transistor to the emitter pin of the three pin power package; and

subsequent standard moulding and follow on process to complete a device packaging.

4. The method of claim 3, wherein the diode is a Schottky diode.

5. A method of fabricating a three terminal high voltage hybrid MOSFET/bipolar transistor power switching device having a collector terminal, a gate bonding terminal with a gate bonding pin and an emitter with an emitter pin, including the steps of:

conductive die attaching a high voltage MOSFET and a high voltage bipolar transistor having a substrate as a drain and a collector terminal respectively, to a main die pad of a three terminal power device, which serves as the collector terminal for the power switching device;

conductive die attaching a diode having a cathode and an anode with the cathode as a substrate to the gate bonding pin of the gate terminal of the three terminal power device;

bonding a gate of the high voltage MOSFET to the gate terminal of the three terminal power device package;

inter-chip bonding of a source of the high voltage MOSFET to a base of the high voltage bipolar transistor;

bonding of the source of the high voltage MOSFET and/or a base of the high voltage bipolar transistor to the anode of the diode;

bonding of an emitter of the high voltage bipolar transistor to the emitter pin of the three pin power; and

subsequent standard moulding and follow on process to complete the device.

6. The method of claim 5, wherein the diode is a Schottky diode.

7. A monolithic three terminal high voltage hybrid bipolar MOSFET/bipolar power switching semiconductor integrated circuit having a collector terminal, a gate terminal and an emitter terminal fabricated by a high voltage planer process including:

a high voltage MOSFET having a body, a gate and a high voltage bipolar transistor, with a substrate having a dopant type as a drain and a collector respectively such that the substrate serves as the collector terminal for the power switching integrated circuit via high doping concentration region of the same type at a back side;

two semiconductor well regions with an opposite dopant type to the substrate serving as a body and a base region for the high voltage MOSFET and high voltage bipolar transistor, respectively;

semiconductor electrodes of the same dopant type as the substrate with high doping density inside the body and base regions serving as a source and an emitter for the high voltage MOSFET and high voltage bipolar transistors, respectively;

poly-silicon thin oxide gate electrodes overlapping the body and the substrate regions serving as the gate for the MOSFET;

wherein;

the gate of the high voltage MOSFET serves as the gate terminal for the power switching integrated circuit;

source of the high voltage MOSFET connecting to the base of the high voltage bipolar transistor;

the body of the high voltage MOSFET connecting either to the source of the high voltage MOSFET, or as an alternative, to an emitter of the high voltage bipolar transistor;

the emitter of the high voltage bipolar transistor serving as an emitter terminal for the power switching integrated circuit; and

a diode having an anode and a cathode with the anode connected to the base of the high voltage bipolar transistor and the cathode connected to the gate terminal of the power switching integrated circuit;

wherein;

the diode is a diode connected bipolar transistor with the following;

a collector with a dopant type opposite to the main substrate as a well on the high voltage collector substrate of the high voltage power switching integrated circuit similar to the body of the high voltage MOSFET, or the base of the high voltage bipolar transistor;

a base inside the collector well with a dopant type opposite from that of the collector well with interconnections to other parts via electrodes similar to the emitter of the high voltage bipolar transistor, or the source of the high voltage MOSFET;

an emitter, either as semiconductor of the same type as the collector at much higher doping density, or as barrier metal silicide; and

the base and collector having terminals which are connected and serve as the cathode while the emitter serves as the anode of the diode.

8. The integrated circuit of claim 7 comprising a mask for fabricating the wells for the body and base regions of the high voltage MOSFET and high voltage bipolar transistor, wherein the collector well of the diode connected bipolar shares the mask for fabricating the wells for the body and base regions of the high voltage MOSFET and high voltage bipolar transistor, or as a separate region fabricated by additional masking.

9. The integrated circuit of claim 7, wherein the collector well of the diode connected bipolar has high doping density regions guarding a low doping density region of the same type with a junction depth less than the high doping region wherein the high doping regions are used for withstanding a high breakdown voltage as well as connecting a low doping density collector well for making connections, the low doping density region serving as an actual collector well inside which the base and emitter of the diode connected bipolar transmitter are formed.

10. The integrated circuit of claim 7, wherein the wells for the body of the high voltage MOSFET and the base of the high voltage bipolar transistor are merged for the case in which the body of the MOSFET is electrically connected to the base of the high voltage bipolar transistor.

11. The integrated circuit of claim 7, wherein the diode is a Schottky diode having an anode and connections to semiconductor regions other than the Schottky diode anode are made via barrier metal silicide.

12. The integrated circuit of claim 7, wherein connections to base region of the high voltage bipolar transistor and the body region of the high voltage MOSFET, and the collector region of the diode connected bipolar transistor using a normal base emitter junction are made via a same kind of semiconductor electrode for the anode of the diode.

13. A monolithic three terminal high voltage hybrid bipolar MOSFET/bipolar power switching semiconductor integrated circuit having a gate terminal, an emitter terminal and a collector substrate fabricated by high voltage super-junction process including:

a high voltage MOSFET having a drain and a high voltage bipolar transistor having a collector, a base and an emitter with a substrate as the drain and collector respectively such that the substrate has a dopant type and serves as a collector terminal for the power switching integrated circuit via a high doping density region of the same type at a back side;

semiconductor well regions with an opposite dopant type to the substrate serving as a body and base regions for the high voltage MOSFET and high voltage bipolar transistor, respectively, with high doping concentration super-junction columns of opposite type of dopant as the main substrate for withstanding a high breakdown voltage;

semiconductor electrodes of the same dopant type as the substrate with high doping density inside the body and base regions serving as the source and an emitter for the high voltage MOSFET and high voltage bipolar transistor respectively;

poly-silicon thin oxide gate electrodes overlapping the body and the substrate regions serving as a gate for the MOSFET;

wherein;

the gate of the high voltage MOSFET serves as a gate terminal for the power switching integrated circuit;

a source terminal of the high voltage MOSFET connecting to the base of the high voltage bipolar transistor;

the body of the high voltage MOSFET connects to the source of the high voltage MOSFET, to the emitter of the high voltage bipolar transistor;

the emitter of the high voltage bipolar transistor serves as an emitter terminal for the power switching integrated circuit; and

a diode having an anode and a cathode with the anode connected to the base of the high voltage bipolar transistor and the cathode connected to the gate terminal of the power switching integrated circuit;

wherein

the diode is a diode connected bipolar transistor with the following;

a collector with dopant type opposite to the main substrate as a well on the high voltage collector substrate of the high voltage power switching integrated circuit similar to the body of the high voltage MOSFET, or the base of the high voltage bipolar transistor, with high doping concentration super-junction columns of opposite type of dopant of the substrate guarding the collector region for withstanding the high breakdown voltage;

a base inside the collector well with a dopant type opposite from that of the collector well with interconnections to other parts via electrodes similar to the emitter regions of the high voltage bipolar transistor, or the source of the high voltage MOSFET;

an emitter, either as semiconductor of the same type as the collector at much higher doping density, or as a barrier metal silicide; and

the base and collector having terminals which are connected and serve as the cathode while the emitter serves as the anode of the diode.

14. The integrated circuit of claim 13 comprising a mask for fabricating the wells for the body and base regions of the high voltage MOSFET and high voltage bipolar transistor, wherein the collector well for the diode connected bipolar shares the mask for fabricating the wells for the body and base regions of the high voltage MOSFET and high voltage bipolar transistors, or as a separate region fabricated by additional masking.

15. The integrated circuit of claim 13, wherein the collector well for the diode connected bipolar has high doping density regions guarding a low doping density region of the same type with a junction depth less than the high doping region, wherein the high doping regions are used for withstanding the high breakdown voltage as well as connecting the low doping density collector well for making connections, and the low doping density region is serving as the actual collector well inside which the base and emitter of the diode connected bipolar device are formed.

16. The integrated circuit of claim 13, wherein the body of the high voltage MOSFET is electrically connected to the base of the high voltage bipolar transistor, and the wells for the body of the high voltage MOSFET and the base of the high voltage bipolar transistor are merged.

17. The integrated Circuit of claim 13, wherein isolation region super-junction columns for the high voltage MOSFET and the high voltage bipolar transistor are merged and isolation regions between them are eliminated.

18. The integrated circuit of claim 13, wherein the diode is a Schottky diode and connections to semiconductor regions other than the Schottky diode anode are made via barrier metal silicide.

19. The integrated circuit of claim 13, wherein connections to base region of the high voltage bipolar transistor and the body region of the high voltage MOSFET, and the collector region of the diode connected bipolar device using normal base emitter junction are made via the same kind of semiconductor electrode for the anode of the diode.

20. A monolithic three terminal high voltage hybrid bipolar MOSFET/bipolar power switching semiconductor integrated circuit having a collector terminal, a gate terminal and an emitter terminal and fabricated by high voltage semi-super-junction process comprising:

a high voltage MOSFET having a body, a gate, a source and a drain and a high voltage bipolar transistor, having a base, a collector and an emitter, with a substrate as the drain and the collector, respectively, such that the substrate has a dopant type and serves as the collector terminal for the power switching integrated circuit via a high doping density region of the same type at a back side;

semiconductor well regions with an opposite dopant type to the substrate serving as the body and base regions for the high voltage MOSFET and high voltage bipolar transistor, respectively, with high doping concentration semi-super-junction columns of opposite type of dopant as a main substrate for withstanding a high breakdown voltage;

semiconductor electrodes of the same dopant type as the substrate with high doping density inside the body and base regions serving as the source and the emitter for the high voltage MOSFET and high voltage bipolar transistor, respectively;

poly-silicon thin oxide gate electrodes overlapping the body and the substrate serving as the gate for the MOSFET;

wherein;

the gate of the high voltage MOSFET serves as the gate terminal for the power switching integrated circuit;

the source of the high voltage MOSFET connecting to the base of the high voltage bipolar transistor;

the body of the high voltage MOSFET connects to the source of the high voltage MOSFET, or to the emitter of the high voltage bipolar transistor;

the emitter of the high voltage bipolar transistor serving as the emitter terminal for the power switching integrated circuit; and

a diode having an anode and a cathode with the anode connected to the base of the high voltage bipolar transistor and the cathode connected to the gate terminal of the power switching integrated circuit;

wherein

the diode is a diode connected bipolar transistor with the following;

a collector having a region with a dopant type opposite to the main substrate as a well on the high voltage collector substrate of the high voltage power switching integrated circuit similar to the body of the high voltage MOSFET, or the base of the high voltage bipolar transistor, with high doping concentration semi-super-junction columns of opposite type of dopant of the substrate guarding the collector region for withstanding the high breakdown voltage;

a base inside the collector well with dopant type opposite from that of the collector well with interconnections to other parts via electrodes similar to the emitter regions of the high voltage bipolar transistor, or the source of the high voltage MOSFET;

an emitter, either as semiconductor of the same type as the collector at much higher doping density, or as barrier metal silicide; and

the base and collector having terminals which are connected and serve as the cathode while the emitter is serving as the anode of the diode.

21. The integrated circuit of claim 20 and comprising a mask for fabricating the wells for the body and base regions of the high voltage MOSFET and high voltage bipolar transistor, wherein the collector well of for the diode connected bipolar shares the mask for fabricating the wells for the body and base regions of the high voltage MOSFET and high voltage bipolar transistor, or as a separate region fabricated by additional masking.

22. The integrated circuit of claim 20, wherein the collector well of the diode connected bipolar has high doping density regions guarding a low doping density region of the same type with a junction depth less than the high doping region wherein the high doping regions are used for withstanding the high breakdown voltage as well as connecting the low doping density collector well for making the connection, the low doping density region serving as the actual collector well inside which the base and emitter of the diode connected bipolar transistor are formed.

23. The integrated circuit of claim 20, wherein the wells for the body of the high voltage MOSFET and the base of the high voltage bipolar transistor are merged for the case in which the body of the high voltage MOSFET is electrically connected to the base of the high voltage bipolar transistor.

24. The integrated circuit of claim 23 wherein isolation region semi-super-junction columns for the high voltage MOSFET and the high voltage bipolar transistor are merged and an isolation region between them are eliminated.

25. The integrated circuit of claim 20, wherein the diode is a Schottky diode and connections to semiconductor regions other than the Schottky diode anode are made via barrier metal silicide.

26. The integrated circuit of claim 20, wherein connections to the base region of the high voltage bipolar transistor and the body region of the high voltage MOSFET, and the collector region of the diode connected bipolar device using normal base emitter junction are made via the same kind of semiconductor electrode for the anode of the diode.