TW201909252A - 半導體元件與其製造方法 - Google Patents

半導體元件與其製造方法 Download PDF

Info

Publication number
TW201909252A
TW201909252A TW106123363A TW106123363A TW201909252A TW 201909252 A TW201909252 A TW 201909252A TW 106123363 A TW106123363 A TW 106123363A TW 106123363 A TW106123363 A TW 106123363A TW 201909252 A TW201909252 A TW 201909252A
Authority
TW
Taiwan
Prior art keywords
dielectric layer
layer
semiconductor device
gate
disposed
Prior art date
Application number
TW106123363A
Other languages
English (en)
Other versions
TWI621162B (zh
Inventor
許修文
葉俊瑩
羅振達
李元銘
Original Assignee
帥群微電子股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 帥群微電子股份有限公司 filed Critical 帥群微電子股份有限公司
Priority to TW106123363A priority Critical patent/TWI621162B/zh
Priority to US15/888,074 priority patent/US20190019869A1/en
Application granted granted Critical
Publication of TWI621162B publication Critical patent/TWI621162B/zh
Publication of TW201909252A publication Critical patent/TW201909252A/zh

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76Unipolar devices, e.g. field effect transistors
    • H01L29/772Field effect transistors
    • H01L29/78Field effect transistors with field effect produced by an insulated gate
    • H01L29/7801DMOS transistors, i.e. MISFETs with a channel accommodating body or base region adjoining a drain drift region
    • H01L29/7802Vertical DMOS transistors, i.e. VDMOS transistors
    • H01L29/7813Vertical DMOS transistors, i.e. VDMOS transistors with trench gate electrode, e.g. UMOS transistors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/401Multistep manufacturing processes
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/402Field plates
    • H01L29/407Recessed field plates, e.g. trench field plates, buried field plates
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/41Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
    • H01L29/423Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions not carrying the current to be rectified, amplified or switched
    • H01L29/42312Gate electrodes for field effect devices
    • H01L29/42316Gate electrodes for field effect devices for field-effect transistors
    • H01L29/4232Gate electrodes for field effect devices for field-effect transistors with insulated gate
    • H01L29/42324Gate electrodes for transistors with a floating gate
    • H01L29/42336Gate electrodes for transistors with a floating gate with one gate at least partly formed in a trench
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/41Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
    • H01L29/423Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions not carrying the current to be rectified, amplified or switched
    • H01L29/42312Gate electrodes for field effect devices
    • H01L29/42316Gate electrodes for field effect devices for field-effect transistors
    • H01L29/4232Gate electrodes for field effect devices for field-effect transistors with insulated gate
    • H01L29/42356Disposition, e.g. buried gate electrode
    • H01L29/4236Disposition, e.g. buried gate electrode within a trench, e.g. trench gate electrode, groove gate electrode
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/43Electrodes ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/49Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
    • H01L29/51Insulating materials associated therewith
    • H01L29/511Insulating materials associated therewith with a compositional variation, e.g. multilayer structures
    • H01L29/512Insulating materials associated therewith with a compositional variation, e.g. multilayer structures the variation being parallel to the channel plane
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/43Electrodes ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/49Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
    • H01L29/51Insulating materials associated therewith
    • H01L29/511Insulating materials associated therewith with a compositional variation, e.g. multilayer structures
    • H01L29/513Insulating materials associated therewith with a compositional variation, e.g. multilayer structures the variation being perpendicular to the channel plane
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007Multistep manufacturing processes
    • H01L29/66075Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
    • H01L29/66409Unipolar field-effect transistors
    • H01L29/66477Unipolar field-effect transistors with an insulated gate, i.e. MISFET
    • H01L29/66674DMOS transistors, i.e. MISFETs with a channel accommodating body or base region adjoining a drain drift region
    • H01L29/66712Vertical DMOS transistors, i.e. VDMOS transistors
    • H01L29/66734Vertical DMOS transistors, i.e. VDMOS transistors with a step of recessing the gate electrode, e.g. to form a trench gate electrode
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76Unipolar devices, e.g. field effect transistors
    • H01L29/772Field effect transistors
    • H01L29/78Field effect transistors with field effect produced by an insulated gate
    • H01L29/7801DMOS transistors, i.e. MISFETs with a channel accommodating body or base region adjoining a drain drift region
    • H01L29/7816Lateral DMOS transistors, i.e. LDMOS transistors
    • H01L29/7825Lateral DMOS transistors, i.e. LDMOS transistors with trench gate electrode
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/28Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
    • H01L21/28008Making conductor-insulator-semiconductor electrodes
    • H01L21/28017Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon
    • H01L21/28158Making the insulator
    • H01L21/28229Making the insulator by deposition of a layer, e.g. metal, metal compound or poysilicon, followed by transformation thereof into an insulating layer
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/41Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
    • H01L29/417Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions carrying the current to be rectified, amplified or switched
    • H01L29/41725Source or drain electrodes for field effect devices
    • H01L29/41741Source or drain electrodes for field effect devices for vertical or pseudo-vertical devices
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/41Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
    • H01L29/417Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions carrying the current to be rectified, amplified or switched
    • H01L29/41725Source or drain electrodes for field effect devices
    • H01L29/41766Source or drain electrodes for field effect devices 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
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/41Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
    • H01L29/423Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions not carrying the current to be rectified, amplified or switched
    • H01L29/42312Gate electrodes for field effect devices
    • H01L29/42316Gate electrodes for field effect devices for field-effect transistors
    • H01L29/4232Gate electrodes for field effect devices for field-effect transistors with insulated gate
    • H01L29/42372Gate electrodes for field effect devices for field-effect transistors with insulated gate characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out
    • H01L29/42376Gate electrodes for field effect devices for field-effect transistors with insulated gate characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out characterised by the length or the sectional shape
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/43Electrodes ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/49Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
    • H01L29/51Insulating materials associated therewith
    • H01L29/518Insulating materials associated therewith the insulating material containing nitrogen, e.g. nitride, oxynitride, nitrogen-doped material

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Ceramic Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Manufacturing & Machinery (AREA)
  • Insulated Gate Type Field-Effect Transistor (AREA)
  • Electrodes Of Semiconductors (AREA)
  • Element Separation (AREA)

Abstract

一種半導體元件的製造方法包含以下步驟。首先,形成磊晶層於基板上。然後,形成體區於磊晶層的上半部分。接著,形成第一溝渠於磊晶層中。之後,依序形成第一介電層、第二介電層以及第三介電層於磊晶層上,其中第三介電層形成第二溝渠,第二溝渠位於第一溝渠中。然後,形成屏蔽層於第二溝渠中。接著,移除第三介電層的上半部分,以使屏蔽層的上半部分凸出於第三介電層。之後,形成第四介電層覆蓋於屏蔽層的上半部分。然後,形成閘極於第三介電層上。最後,形成源極於位於閘極之四周的磊晶層中。

Description

半導體元件與其製造方法
本發明是有關於一種半導體元件與其製造方法。
功率半導體仍是許多電力電子系統的主要元件。在現今功率半導體的應用領域中,能源使用效率的提升、耐壓能力以及降低導通電阻的表現是非常重要的能力指標,其中功率元件特性能力提升與封裝寄生電性減少為兩大主要改善方向。
為了進一步改善功率半導體的各項特性,相關領域莫不費盡心思開發。如何能提供一種具有較佳特性的功率半導體,實屬當前重要研發課題之一,亦成為當前相關領域亟需改進的目標。
本發明之一技術態樣是在提供一種半導體元件與其製造方法,藉由適當的結構設計,使半導體元件具有較高的崩潰電壓、較低的導通電阻。另外,利用特殊的製程設計,將能有效降低製造成本。
根據本發明一實施方式,一種半導體元件的製造方法包含以下步驟。首先,形成磊晶層於基板上。然後,形成體區於磊晶層的上半部分。接著,形成第一溝渠於磊晶層中。之後,依序形成第一介電層、第二介電層以及第三介電層於磊晶層上,其中第三介電層形成第二溝渠,第二溝渠位於第一溝渠中。然後,形成屏蔽層於第二溝渠中。接著,移除第三介電層的上半部分,以使屏蔽層的上半部分凸出於第三介電層。之後,形成第四介電層覆蓋於屏蔽層的上半部分。然後,形成閘極於第三介電層上。最後,形成源極於位於閘極之四周的磊晶層中。
於本發明之一或複數個實施方式中,第四介電層為藉由熱氧化屏蔽層而形成。
於本發明之一或複數個實施方式中,屏蔽層的頂面的高度在體區頂面的高度與底面高度之間。
於本發明之一或複數個實施方式中,形成閘極於第三介電層的步驟前,更包括移除第二介電層的上半部分。
於本發明之一或複數個實施方式中,第四介電層的頂面設置高度大於磊晶層的頂面的設置高度。
根據本發明另一實施方式,一種半導體元件包含基板、磊晶層、體區、第三介電層、屏蔽層、第四介電層、閘極以及源極。磊晶層位於基板上。體區位於磊晶層的上半部分中。第三介電層設置於磊晶層的第一溝渠中,並形成第二溝渠。屏蔽層具有上半部分與下半部分,其中下半部分設 置於第二溝渠內,上半部分凸出於第三介電層。第四介電層覆蓋屏蔽層的上半部分。閘極設置於磊晶層中與第三介電層上,其中至少部分第四介電層設置於屏蔽層的上半部分與閘極之間。源極設置於位於閘極之四周的磊晶層中。
於本發明之一或複數個實施方式中,至少部分該閘極位於該屏蔽層的該上半部分的上方。
於本發明之一或複數個實施方式中,半導體元件更包含第一介電層與第二介電層。第一介電層設置於磊晶層與第三介電層之間,其中第一介電層之材質為二氧化矽。第二介電層設置於第一介電層與第三介電層之間,其中第二介電層之材質為氮化矽。
於本發明之一或複數個實施方式中,第三介電層之材質為四乙氧基矽烷,第四介電層藉由熱氧化屏蔽層形成。
於本發明之一或複數個實施方式中,屏蔽層的頂面高度在體區的頂面高度與底面的高度之間。
於本發明之一或複數個實施方式中,第四介電層的設置高度大於磊晶層的頂面的設置高度。
本發明上述實施方式藉由設置屏蔽層於磊晶層中,使半導體元件在逆向偏壓操作時屏蔽層會產生電場夾擠效應,因而達成電荷平衡(Charge Balance)與電場舒緩效果(Reduce Surface Field,RESURF)的效果,進而使汲極與閘極之間形成較和緩的電場分佈。於是,汲極與閘極之 間的距離不用太長即可使半導體元件有較高的崩潰電壓,並因而降低半導體元件的導通電阻與體積。
另外,利用熱氧化屏蔽層的方式,僅需要使用一個製程就可以形成設置於閘極與屏蔽層之間的介電層。於是,相較於傳統製程,製造半導體元件所需的製程將能大幅減少,進而有效降低製造成本。
100‧‧‧半導體元件
110‧‧‧基板
120‧‧‧磊晶層
120t、140t‧‧‧頂面
121‧‧‧溝渠
122‧‧‧體區
129‧‧‧接觸窗
131‧‧‧第一介電層
132‧‧‧第二介電層
133‧‧‧第三介電層
134‧‧‧第二溝渠
135‧‧‧第四介電層
136‧‧‧第五介電層
138‧‧‧第三溝渠
140‧‧‧屏蔽層
140d‧‧‧下半部分
140u‧‧‧上半部分
150‧‧‧閘極
160‧‧‧源極
171‧‧‧金屬層
第1A圖至第1G圖繪示依照本發明一實施方式之半導體元件的製造方法各步驟的剖面圖。
第2A圖至第2C圖繪示依照本發明另一實施方式之半導體元件的製造方法各步驟的剖面圖。
以下將以圖示揭露本發明之複數個實施方式,為明確說明起見,許多實務上的細節將在以下敘述中一併說明。然而,應瞭解到,這些實務上的細節不應用以限制本發明。也就是說,在本發明部分實施方式中,這些實務上的細節是非必要的。此外,為簡化圖式起見,一些習知慣用的結構與元件在圖式中將以簡單示意的方式繪示之。
第1A圖至第1G圖繪示依照本發明一實施方式之半導體元件100的製造方法各步驟的剖面圖。具體而言,半導體元件100為功率半導體元件。
如第1A圖所繪示,首先,形成磊晶層120於基板110上。具體而言,基板110之材質可為單晶矽。磊晶層120之材質可為單晶矽。
然後,形成體區122於磊晶層120的上半部分中。具體而言,體區122的形成方法為離子佈植(Ion Implantation)與驅入擴散(Drive In)。
接著,形成第一溝渠121於磊晶層120中。具體而言,第一溝渠121的形成方法例如為蝕刻。
然後,依序形成第一介電層131、第二介電層132以及第三介電層133於磊晶層120上,其中第三介電層133形成第二溝渠134,第二溝渠134位於第一溝渠121中。具體而言,第一介電層131之材質可為二氧化矽。第二介電層132之材質可為氮化矽。第三介電層133之材質可為四乙氧基矽烷(Tetraethoxysilane,TEOS)。第一介電層131可藉由熱氧化磊晶層120而形成。第二介電層132、第三介電層133可分別藉由物理氣相沉積、化學氣相沉積或其組合而形成。
如第1B圖所繪示,形成屏蔽層140於第二溝渠134中。具體而言,首先形成屏蔽層140於第三介電層133上(即第二溝渠134中與第三介電層133的頂面上)。然後,移除屏蔽層140的上半部分,僅留下位於第二溝渠134中的屏蔽層140。屏蔽層140之材質可為多晶矽。屏蔽層140可藉由物理氣相沉積、化學氣相沉積或其組合而形成。屏蔽層 140的移除方法可為蝕刻。另外,屏蔽層140的頂面的高度在體區122的頂面的高度與底面的高度之間。
如第1C圖所繪示,移除第三介電層133的上半部分而保留位於第一溝渠121中的第三介電層133,以使屏蔽層140的上半部分140u凸出於第三介電層133。具體而言,第三介電層133的移除方法可為濕蝕刻。
如第1D圖所繪示,形成第四介電層135於屏蔽層140的上半部分140u上,因而使第四介電層135覆蓋屏蔽層140的上半部分140u。具體而言,第四介電層135之材質可為二氧化矽。第四介電層135為藉由熱氧化屏蔽層140而形成。此處需要注意的是,第二介電層132可以在熱氧化屏蔽層140的時候保護位於其下的其他結構(例如介電層131)不受影響。
如第1D圖與第1E圖所繪示,移除第二介電層132的上半部分(即設置高度大於第三介電層133的頂面的設置高度的部分),以使第二介電層132的頂面高度與介電層133的頂面高度大致相同。具體而言,第二介電層132的移除方法可為濕蝕刻。需要注意的是,在其他實施方式中,第二介電層132的上半部分可能不會被移除。
然後,形成閘極150於磊晶層120中的第三溝渠138中和第三介電層133上。具體而言,首先形成閘極150於第三溝渠138中與第一介電層131的頂面上。然後,移除閘極150的上半部分,僅留下位於磊晶層120中第三溝渠138中的閘極150。於是,閘極150設置於介電層132、133、135 上且直接接觸第一介電層131。閘極150之材質可為多晶矽。閘極150可藉由物理氣相沉積、化學氣相沉積或其組合而形成。閘極150的移除方法可為蝕刻。
如第1F圖所繪示,形成源極160於位於閘極150之四周的體區122(磊晶層120)中。源極160的形成方法為離子佈植與驅入擴散。
如第1G圖所繪示,形成介電層136於介電層131與閘極150上。具體而言,介電層136之材質可為二氧化矽或氮化矽。介電層136可藉由物理氣相沉積、化學氣相沉積或其組合而形成。
然後,形成穿過介電層131、136且直接接觸體區122與源極160的金屬層171。具體而言,首先形成接觸窗129於體區122、介電層131、136與源極160中。接觸窗129的形成方式可為蝕刻。然後,形成金屬層171於接觸窗129中與介電層136的頂面上。再來,移除金屬層171的上半部分,僅留下位於接觸窗129中的金屬層171。金屬層171之材質可為鋁或銅或鎢等金屬所構成。金屬層171可藉由電化學沉積製程(Electrochemical Deposition)、物理氣相沉積製程、化學氣相沉積製程或其組合形成。金屬層171的上半部分可藉由化學機械平坦化製程(Chemical Mechanical Planarization,CMP)而移除。
在半導體元件100中,基板110作為汲極。藉由設置屏蔽層140於磊晶層120中,半導體元件100在逆向偏壓操作時屏蔽層140會產生電場夾擠效應,因而達成電荷平 衡(Charge Balance)與電場舒緩(Reduce Surface Field,RESURF)的效果,進而使基板110與閘極150之間形成較和緩的電場分佈。於是,基板110與閘極150之間的距離不用太長即可使半導體元件100具有較高的崩潰電壓,並因而降低半導體元件100的導通電阻。於是,半導體元件100的其他參數(舉例來說,磊晶層120的厚度與阻值)將可以有更大的最佳化調整空間。
另外,利用熱氧化屏蔽層140的方式,僅需要使用一個製程就可以形成設置於閘極150與屏蔽層140之間的第四介電層135。於是,相較於傳統製程,製造半導體元件100所需的製程將能大幅減少,進而有效降低製造成本。
本製造方法可以相容於傳統功率半導體元件的相關製程,因此僅需微調原有製程即可製造半導體元件100。另外,屏蔽層140可以為接地或浮接。屏蔽層140亦可以使半導體元件100具有較佳的電容特性,而較低的導通電阻與較佳的電容特性將能減少半導體元件100導通與切換時的效能損失。
第2A圖至第2C圖繪示依照本發明另一實施方式之半導體元件100的製造方法各步驟的剖面圖。本實施方式的製造方法與前述實施方式的製造方法大致相同,以下主要將介紹其相異處。
如第2A圖所繪示,在移除屏蔽層140的上半部分的時候,使最後氧化過的屏蔽層140的頂面140t的設置高度小於或等於體區122的頂面120t的設置高度,即屏蔽層 140的頂面的高度在體區122的頂面的高度與底面的高度之間。在此實施例為屏蔽層140的頂面140t接近等於體區122的頂面120t的設置高度。
如第2B圖所繪示,屏蔽層140的頂面140t接近等於體區122的頂面120t的設置高度,在第四介電層135覆蓋到屏蔽層140後,第四介電層135頂面高於體區122的頂面120t的設置高度,所以閘極150將不會設置於第四介電層135上方而是位於第四介電層135兩側。
如第2C圖所繪示,本實施方式所形成的半導體元件100基本上與第1G圖所形成的半導體元件100相同,主要差異在於,在本實施方式中,第四介電層135的頂面高度大於或等於磊晶層120的頂面120t的設置高度(源極160為形成於體區122中),所以閘極150沒有設置於第四介電層135的頂面上。
本發明另一實施方式提供一種半導體元件100。如第1G圖所繪示,半導體元件100包含基板110、磊晶層120、介電層131、132、133、135、136、屏蔽層140、閘極150、體區122、源極160以及金屬層171。
磊晶層120設置於基板110上。介電層133設置於磊晶層120中。屏蔽層140具有上半部分140u與下半部分140d,其中下半部分140d設置於第三介電層133中,上半部分凸出於第三介電層133。第四介電層135覆蓋屏蔽層140的上半部分140u。閘極150設置於磊晶層120中與第三介電層133上,其中部分第四介電層135設置於屏蔽層140的上 半部分140u與閘極150之間。源極160設置於位於閘極150之四周的磊晶層120中。
具體而言,至少部分閘極150位於屏蔽層140的上半部分140u的上方。換句話說,部分閘極150設置於第四介電層135的頂面上。
第三介電層133之材質可為四乙氧基矽烷(Tetraethoxysilane,TEOS)。第四介電層135之材質可為二氧化矽。
具體而言,第一介電層131設置於磊晶層120與第三介電層133之間,其中第一介電層131之材質為二氧化矽。第一介電層131亦設置於源極160與閘極150之間與源極160的頂面上。
具體而言,第二介電層132設置於第一介電層131與第三介電層133之間,其中第二介電層132之材質為氮化矽,但並不限於此。在一些實施方式中,第二介電層132亦設置於源極160與閘極150之間。
具體而言,體區122設置於位於閘極150之四周的磊晶層120中且設置於源極160下方。第一介電層131亦設置於體區122與閘極150之間。
具體而言,第五介電層136設置於閘極150的頂面上與第一介電層131的頂面上(即源極160的上方)。金屬層171穿過介電層131、136而和體區122與源極160直接接觸。
本發明又一實施方式提供一種半導體元件100。如第2C圖所繪示,本實施方式的半導體元件100基本上與第1G圖的半導體元件100大致相同,以下主要將描述其差異處。
屏蔽層140具有頂面140t,磊晶層120具有頂面120t,第四介電層135的設置高度大於磊晶層120的頂面120t的設置高度。
在此同時,閘極150沒有設置於屏蔽層140的上半部分140u的上方。換句話說,閘極150沒有設置於第四介電層135的頂面上。
在半導體元件中,基板作為汲極。藉由設置屏蔽層於磊晶層中,半導體元件在逆向偏壓操作時屏蔽層會產生電場夾擠效應,因而達成電荷平衡與電場舒緩的效果,進而使基板與閘極之間形成較和緩的電場分佈。於是,基板與閘極之間的距離不用太長即可使半導體元件具有較高的崩潰電壓,並因而降低半導體元件的導通電阻。於是,半導體元件的其他參數(舉例來說,磊晶層的厚度與阻值)將可以有更大的最佳化調整空間。
另外,利用熱氧化屏蔽層的方式,僅需要使用一個製程就可以形成設置於閘極與屏蔽層之間的介電層。於是,相較於傳統製程,製造半導體元件所需的製程將能大幅減少,進而有效降低製造成本。
本製造方法可以相容於傳統功率半導體元件的相關製程,因此僅需微調原有製程即可製造半導體元件。另 外,屏蔽層可以為接地或浮接。屏蔽層亦可以使半導體元件具有較佳的電容特性,而較低的導通電阻與較佳的電容特性將能減少半導體元件導通與切換時的效能損失。
雖然本發明已以實施方式揭露如上,然其並非用以限定本發明,任何熟習此技藝者,在不脫離本發明之精神和範圍內,當可作各種之更動與潤飾,因此本發明之保護範圍當視後附之申請專利範圍所界定者為準。

Claims (11)

  1. 一種半導體元件的製造方法,包含:形成一磊晶層於一基板上;形成一體區於該磊晶層的上半部分;形成一第一溝渠於該磊晶層中;依序形成一第一介電層、一第二介電層以及一第三介電層於該磊晶層上,其中該第三介電層形成一第二溝渠,該第二溝渠位於該第一溝渠中;形成一屏蔽層於該第二溝渠中;移除該第三介電層的一上半部分,以使該屏蔽層的一上半部分凸出於該第三介電層;形成一第四介電層覆蓋於該屏蔽層的該上半部分;形成一閘極於該第三介電層上;以及形成一源極於位於該閘極之四周的該磊晶層中。
  2. 如請求項1所述半導體元件的製造方法,其中該第四介電層為藉由熱氧化該屏蔽層而形成。
  3. 如請求項1所述半導體元件的製造方法,其中該屏蔽層的頂面高度在該體區的頂面高度與底面的高度之間。
  4. 如請求項1所述半導體元件的製造方法,形成該閘極於該第三介電層的步驟前,更包括移除該第二介電層的上半部分。
  5. 如請求項1所述半導體元件的製造方法,其中該第四介電層的頂面設置高度大於該磊晶層的頂面設置高度。
  6. 一種半導體元件,包含:一基板;一磊晶層,位於該基板上;一體區,位於該磊晶層的上半部分中;一第三介電層,設置於該磊晶層的一第一溝渠中,並形成一第二溝渠;一屏蔽層,具有一上半部分與一下半部分,其中該下半部分設置於該第二溝渠內,該上半部分凸出於該第三介電層;一第四介電層,覆蓋該屏蔽層的該上半部分;一閘極,設置於該磊晶層中與該第三介電層上,其中至少部分該第四介電層設置於該屏蔽層的該上半部分與該閘極之間;以及一源極,設置於位於該閘極之四周的該磊晶層中。
  7. 如請求項6所述之半導體元件,其中至少部分該閘極位於該屏蔽層的該上半部分的上方。
  8. 如請求項6所述之半導體元件,更包含:一第一介電層,設置於該磊晶層與該第三介電層之間,其中該第一介電層之材質為二氧化矽;以及 一第二介電層,設置於該第一介電層與該第三介電層之間,其中該第二介電層之材質為氮化矽。
  9. 如請求項6所述之半導體元件,其中該第三介電層之材質為四乙氧基矽烷,該第四介電層藉由熱氧化該屏蔽層形成。
  10. 如請求項6所述之半導體元件,其中該屏蔽層的頂面高度在體區的頂面高度與底面的高度之間。
  11. 如請求項6所述之半導體元件,其中該第四介電層的設置高度大於磊晶層的頂面的設置高度。
TW106123363A 2017-07-12 2017-07-12 半導體元件與其製造方法 TWI621162B (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
TW106123363A TWI621162B (zh) 2017-07-12 2017-07-12 半導體元件與其製造方法
US15/888,074 US20190019869A1 (en) 2017-07-12 2018-02-04 Semiconductor device and method for manufacturing the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
TW106123363A TWI621162B (zh) 2017-07-12 2017-07-12 半導體元件與其製造方法

Publications (2)

Publication Number Publication Date
TWI621162B TWI621162B (zh) 2018-04-11
TW201909252A true TW201909252A (zh) 2019-03-01

Family

ID=62639904

Family Applications (1)

Application Number Title Priority Date Filing Date
TW106123363A TWI621162B (zh) 2017-07-12 2017-07-12 半導體元件與其製造方法

Country Status (2)

Country Link
US (1) US20190019869A1 (zh)
TW (1) TWI621162B (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4009378A1 (en) * 2020-12-01 2022-06-08 Nexperia B.V. A semiconductor device and a method of manufacturing of a semiconductor device

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8497549B2 (en) * 2007-08-21 2013-07-30 Fairchild Semiconductor Corporation Method and structure for shielded gate trench FET
US8044459B2 (en) * 2008-11-10 2011-10-25 Infineon Technologies Austria Ag Semiconductor device with trench field plate including first and second semiconductor materials
JP2013115225A (ja) * 2011-11-29 2013-06-10 Toshiba Corp 電力用半導体装置およびその製造方法
DE102014108966B4 (de) * 2014-06-26 2019-07-04 Infineon Technologies Ag Halbleitervorrichtung mit thermisch gewachsener Oxidschicht zwischen Feld- und Gateelektrode und Herstellungsverfahren
US9917184B2 (en) * 2015-07-24 2018-03-13 Semiconductor Components Industries, Llc Semiconductor component that includes a clamping structure and method of manufacturing the semiconductor component

Also Published As

Publication number Publication date
TWI621162B (zh) 2018-04-11
US20190019869A1 (en) 2019-01-17

Similar Documents

Publication Publication Date Title
TWI484567B (zh) 半導體結構與其製造方法
KR100970282B1 (ko) 트렌치 mosfet 및 그 제조방법
CN104157688A (zh) 具有槽屏蔽电极结构的半导体器件
CN101740612A (zh) 用于具有槽屏蔽电极的半导体器件的接触结构和方法
US6800509B1 (en) Process for enhancement of voltage endurance and reduction of parasitic capacitance for a trench power MOSFET
JP2018082114A (ja) 半導体装置の製造方法
TWI615889B (zh) 功率金氧半導體場效電晶體的製造方法
TWI599041B (zh) 具有底部閘極之金氧半場效電晶體功率元件及其製作方法
TWI567931B (zh) 半導體元件與其製造方法
TWI639232B (zh) 溝槽式功率半導體元件及其製造方法
JP2008118011A (ja) ワイドバンドギャップ半導体縦型mosfetとその製造方法。
TW201724218A (zh) 積體電路
US20180337236A1 (en) Trench power semiconductor component and method of manufacturing the same
US11855201B2 (en) Semiconductor structure
JP5556863B2 (ja) ワイドバンドギャップ半導体縦型mosfet
TWI751431B (zh) 具有低閃爍雜訊的半導體裝置及其形成方法
CN107403838B (zh) 功率金氧半导体场效晶体管
TWI643253B (zh) 功率金氧半導體場效電晶體的製造方法
CN114284149B (zh) 一种屏蔽栅沟槽场效应晶体管的制备方法
TWI621162B (zh) 半導體元件與其製造方法
US9543427B2 (en) Semiconductor device and method for fabricating the same
US11081556B2 (en) Silicon carbide semiconductor device
CN109585547B (zh) 沟槽式功率半导体元件及其制造方法
CN108962972B (zh) 沟槽式功率半导体元件及其制造方法
TW201444082A (zh) 功率半導體元件之製法及結構