阅读说明：本技术 一种高效整流器及其制造方法 (A kind of high efficiency rectifier and its manufacturing method ) 是由 陈文锁 徐向涛 张成方 廖瑞金 于 2019-08-02 设计创作，主要内容包括：本发明公开了一种高效整流器及其制造方法,高效整流器包括下电极层、重掺杂第一导电类型衬底层、第一导电类型漂移层、沟槽栅介质区、沟槽栅填充区、肖特基势垒接触区、隔离介质区和上电极层。制造方法步骤为：1)准备重掺杂第一导电类型衬底层；2)形成第一导电类型漂移层；3)在第一导电类型漂移层表面刻蚀出槽型；4)形成沟槽栅介质区；5)形成沟槽栅填充区；6)形成隔离介质区；7)形成肖特基势垒接触区；8)形成上电极层；9)形成下电极层。本发明在不增加制造工艺步骤和制造成本的基础上获得反向恢复时间短,开关损耗小的性能。(The invention discloses a kind of high efficiency rectifier and its manufacturing method, high efficiency rectifier includes lower electrode layer, the first conductivity type substrate of heavy doping floor, the first conduction type drift layer, trench gate dielectric area, trench gate fill area, Schottky Barrier Contact area, spacer medium area and upper electrode layer.Manufacturing method step are as follows: 1) prepare the first conductivity type substrate of heavy doping layer；2) the first conduction type drift layer is formed；3) go out groove profile in the first conduction type drift layer surface etch；4) trench gate dielectric area is formed；5) trench gate fill area is formed；6) spacer medium area is formed；7) Schottky Barrier Contact area is formed；8) upper electrode layer is formed；9) lower electrode layer is formed.It is short that the present invention obtains reverse recovery time on the basis of not increasing manufacturing technology steps and manufacturing cost, the small performance of switching loss.)

1. a kind of high efficiency rectifier, which is characterized in that mainly include lower electrode layer (1), heavy doping the first conductivity type substrate layer (2), the first conduction type drift layer (3), trench gate dielectric area (4), trench gate fill area (5), Schottky Barrier Contact area (6), spacer medium area (7) and upper electrode layer (8)；

The first conductivity type substrate of heavy doping layer (2) is covered on lower electrode layer (1)；

The first conduction type drift layer (3) is covered on heavy doping the first conductivity type substrate layer (2).

The trench gate dielectric area (4) is U-type groove；

The trench gate dielectric area (4) is covered on the part of the surface on the first conduction type drift layer (3)；

The trench gate fill area (5) is filled in trench gate dielectric area (4)；

The Schottky Barrier Contact area (6) is covered on the part of the surface on the first conduction type drift layer (3)；

The Schottky Barrier Contact area (6) and trench gate dielectric area (4) are spaced apart；

The medium isolation (7) is completely covered on trench gate fill area (5)；

The upper electrode layer (8) is covered on Schottky Barrier Contact area (6) and medium isolation (7).

2. a kind of high efficiency rectifier according to claim 1, it is characterised in that: the trench gate fill area (5) and power on Pole layer (8) does not contact.

3. a kind of high efficiency rectifier according to claim 1 or 2, it is characterised in that: the medium isolation (7) covers ditch The part of the surface in slot gate medium area (4)；The upper electrode layer (8) goes back the part of the surface in covering groove gate medium area (4).

4. a kind of high efficiency rectifier according to claim 1, it is characterised in that: the medium isolation (7) is completely covered On trench gate dielectric area (4).

5. a kind of high efficiency rectifier according to claim 1, it is characterised in that: the trench gate dielectric area (4) is by one Or multiple repetitions and the structural unit not being connected are constituted.

6. a kind of high efficiency rectifier according to claim 1, it is characterised in that: the Schottky Barrier Contact area (6) by One or more repeats and the structural unit not being connected is constituted.

7. a kind of manufacturing method of claim 1 to 6 high efficiency rectifier, which is characterized in that mainly comprise the steps that

1) prepare the first conductivity type substrate of heavy doping layer (2)；

2) the first conduction type drift layer (3) is formed；

3) go out groove profile in first conduction type drift layer (3) surface etch；

4) trench gate dielectric area (4) are formed；

5) trench gate fill area (5) are formed；

6) spacer medium area (7) are formed；

7) Schottky Barrier Contact area (6) are formed；

8) upper electrode layer (8) are formed；

9) lower electrode layer (1) is formed.

8. a kind of manufacturing method of high efficiency rectifier according to claim 7, it is characterised in that: the heavy doping first is led Electric type substrates layer (2) and the first conduction type drift layer (3) use semiconductor material, mainly include silicon and silicon carbide.

The material of the trench gate dielectric area (4) is earth silicon material, silicon oxynitride or hafnium oxide；

The material of the trench gate fill area (5) is polysilicon；The polycrystalline silicon material passes through original flavor doping way or impurity The mode of injection after annealing is completed to adulterate；

The material of the Schottky Barrier Contact area (6) is Schottky barrier metal or advanced silicide；The advanced silicide Including titanium silicon, platinum silicon alloy and nickel platinum silicon alloy.

Technical field

The present invention relates to field of semiconductor devices, specifically a kind of high efficiency rectifier and its manufacturing method.

Background technique

Schottky barrier diode (SBD) is the normal power rectifier of mesolow application field, but due to image charge Caused potential barrier reduces effect, and the levels of leakage of SBD is significantly increased with backward voltage asymptotic breakdown voltage.Trench schottky Barrier diode, also referred to as trench MOS barrier Schottky (TMBS) rectifier, due to introducing the electric field pinch off of trench MOS structure Effect makes reverse leakage level be significantly reduced, while extension drift layer electric field is enhanced, to make forward conduction voltage drop Also it is significantly reduced.But in existing TMBS structure, due to the presence of trench MOS structure, significantly increase barrier capacitance, from And the reverse recovery time of existing TMBS is longer, switching loss is larger.

Summary of the invention

Present invention aim to address problems of the prior art.

To realize the present invention purpose and the technical solution adopted is that a kind of such, high efficiency rectifier, mainly include lower electricity Pole layer, the first conductivity type substrate of heavy doping layer, the first conduction type drift layer, trench gate dielectric area, trench gate fill area, Xiao Te Ji barrier contact area, spacer medium area and upper electrode layer.

The first conductivity type substrate of heavy doping layer is covered on lower electrode layer.

The first conduction type drift layer is covered on heavy doping the first conductivity type substrate layer.

The trench gate dielectric area is U-type groove.

The trench gate dielectric area is covered on the part of the surface on the first conduction type drift layer.

Further, the trench gate dielectric area is made of one or more structural units for repeating and not being connected.

The trench gate fill area is filled in trench gate dielectric area.

Further, the trench gate fill area and upper electrode layer do not contact.

The Schottky Barrier Contact area is covered on the part of the surface on the first conduction type drift layer.

The Schottky Barrier Contact area and trench gate dielectric area are spaced apart.

Further, the Schottky Barrier Contact area is made of one or more structural units for repeating and not being connected.

The medium isolation is completely covered on trench gate fill area.

The upper electrode layer is covered on Schottky Barrier Contact area and medium isolation.

Preferably, the part of the surface in the medium isolation covering groove gate medium area.The upper electrode layer also covers ditch The part of the surface in slot gate medium area.

Preferably, the medium isolation is completely covered on trench gate dielectric area.

A kind of manufacturing method of high efficiency rectifier, mainly comprises the steps that

1) prepare the first conductivity type substrate of heavy doping layer.

2) the first conduction type drift layer is formed.

Heavy doping the first conductivity type substrate layer and the first conduction type drift layer use semiconductor material, main to wrap Include silicon and silicon carbide.

3) go out groove profile in the first conduction type drift layer surface etch.

4) trench gate dielectric area is formed.

The material of the trench gate dielectric area is earth silicon material, silicon oxynitride or hafnium oxide.

5) trench gate fill area is formed.

The material of the trench gate fill area is polysilicon.The polycrystalline silicon material passes through original flavor doping way or impurity The mode of injection after annealing is completed to adulterate.

6) spacer medium area is formed.

7) Schottky Barrier Contact area is formed.

The material in the Schottky Barrier Contact area is Schottky barrier metal or advanced silicide.The advanced silicide Including titanium silicon, platinum silicon alloy and nickel platinum silicon alloy.

8) upper electrode layer is formed.

9) lower electrode layer is formed.

The solution have the advantages that unquestionable.It is longer for device reverse recovery time, switching loss is larger etc. Problem, the present invention pass through the optimization of device new structural design and manufacturing process, reach and do not increasing manufacturing technology steps and system Cause acquisition reverse recovery time on the basis of this short, the small performance of switching loss.(also referred to as with existing trench schottky diode TMBS) rectifier is compared, and the present invention passes through the optimization of device new structural design and manufacturing process, is reached and is not being increased manufacture work Acquisition reverse recovery time is short on the basis of skill step and manufacturing cost, the small performance of switching loss.

Detailed description of the invention

Fig. 1 is a kind of 5 structural schematic diagram of embodiment of high efficiency rectifier provided by the invention；

Fig. 2 is a kind of 6 structural schematic diagram of embodiment of high efficiency rectifier provided by the invention；

Fig. 3 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

Fig. 4 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

Fig. 5 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

Fig. 6 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

Fig. 7 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

Fig. 8 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

Fig. 9 is a kind of 7 structural schematic diagram of embodiment of high efficiency rectifier manufacturing method provided by the invention；

In figure: including lower electrode layer 1, the first conductivity type substrate of heavy doping layer 2, the first conduction type drift layer 3, groove Gate medium area 4, trench gate fill area 5, Schottky Barrier Contact area 6, spacer medium area 7 and upper electrode layer 8.

Specific embodiment

Below with reference to embodiment, the invention will be further described, but should not be construed the above-mentioned subject area of the present invention only It is limited to following embodiments.Without departing from the idea case in the present invention described above, according to ordinary skill knowledge and used With means, various replacements and change are made, should all include within the scope of the present invention.