CN114843225A - 一种集成MIS-HEMT器件和GaN肖特基二极管的方法及应用 - Google Patents

一种集成MIS-HEMT器件和GaN肖特基二极管的方法及应用 Download PDF

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CN114843225A
CN114843225A CN202110141718.2A CN202110141718A CN114843225A CN 114843225 A CN114843225 A CN 114843225A CN 202110141718 A CN202110141718 A CN 202110141718A CN 114843225 A CN114843225 A CN 114843225A
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张斌
王金延
李梦军
陶倩倩
王鑫
汪晨
吴文刚
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Abstract

本发明公开了一种集成MIS‑HEMT器件和GaN肖特基二极管的方法及应用,属于电力电子技术中功率半导体器件领域。本发明将MIS‑HEMT器件和GaN肖特基二极管在器件宽度方向上进行交叉设置,形成叉指并联结构,且MIS‑HEMT器件和GaN肖特基二极管采用同样的湿法刻蚀工艺。与现有技术相比,本发明制备的开关器件具有正向阈值电压、更高正、反向导通电流以及更低反向开启电压,从而提升整个器件的击穿电压,实现更低的开关损耗、更小的占用面积以及更高的转换速率以及更高的工作电压。

Description

一种集成MIS-HEMT器件和GaN肖特基二极管的方法及应用
技术领域
本发明属于电力电子技术中功率半导体器件领域,具体涉及一种集成MIS-HEMT器件和 GaN肖特基二极管的方法。
背景技术
电力电子技术是应用于电力领域的电子技术,主要是使用电力电子器件对电能进行变换 和控制的技术,其变换的功率从1W以下到GW以上。通常所拥有的电力为直流或交流电, 为了对这些电力进行应用,需要对其进行变化,包括整流、直流斩波、交流控制和逆变。在 电能转换电路中,需要用到晶体管作为开关器件实现变换功能,而在部分电路的应用中,如 DC-AC逆变器中,晶体管在实现正向导通的同时,还需要为电路提供一个低损耗的反向续流 通路,来防止由于晶体管的突然关断而引入的反向电压尖刺。如果不对该电压尖刺加以抑制, 那么瞬时的高压可能会导致器件的寿命下降,甚至引发器件击穿。相比于传统的Si基电力电 子器件,GaN基HEMT器件拥有高击穿电压、高电子迁移率以及高转换效率等优点,但是传 统的GaN器件为耗尽型器件,为了保证器件关断,通常需要设计复杂的驱动电路;另一方面, GaN基HEMT器件缺少内部集成的反向续流二极管,需要在外部并联一个二极管,然而,并 联的二极管会增加器件的导通电阻和芯片面积。因此,将GaN基HEMT器件和具有低导通 电压的二极管集成在一起至关重要。
发明内容
本发明的目的在于提供一种集成MIS-HEMT器件和GaN肖特基二极管的方法及应用。 本发明具有正阈值电压、高转换效率、高转换速率、低开关损耗以及小体积等优点。
本发明提供如下技术方案:
一种集成GaN增强型凹槽结构MIS-HEMT器件和GaN肖特基二极管的方法,具体包括以下步骤:
1)外延片准备:Si衬底上通过MOCVD技术生长的带有GaN帽层的AlGaN/GaN异质结结构;
2)采用干法刻蚀技术刻蚀MIS-HEMT器件栅下及二极管阳极区的GaN帽层,露出AlGaN 层,未刻蚀区域的GaN帽层作为氧化腐蚀的掩膜层;
3)将外延片放置于620~680℃的高温氧化炉中,通入氧气氧化40~60分钟,在该温度下,GaN材料无法被氧化,而AlGaN材料则很容易被氧化,因此只有MIS-HEMT器件栅下及二 极管阳极未被GaN帽层覆盖的区域的AlGaN材料被完全氧化;
4)将氧化后的外延片放置于70~80℃的TMAH或KOH液体中腐蚀50~70分钟,使得MIS-HEMT器件栅下及二极管阳极被氧化的AlGaN层完全腐蚀掉,MIS-HEMT器件栅下形 成凹槽结构,同时二极管的阳极也形成凹槽结构,MIS-HEMT器件和二极管的凹槽结构在 同一工艺步骤中制作在同一宽度方向上。由于该刻蚀工艺能够自停止在GaN缓冲层,因此能 够在保证不损伤界面的情况下,实现较高的正向阈值电压;除了MIS-HEMT器件栅以外,有 源区部分的二维电子气得到保留,因此能够在导通时实现高的导通电流;
5)生长栅介质层;
6)在MIS-HEMT器件的源端和漏端区域制作欧姆接触金属,其中,漏端的欧姆接触金属 同时也是二极管的阴极金属;
7)通过F离子注入的手段破坏非器件部分的晶格,形成电学隔离;
8)对二极管阳极部分的介质层进行刻蚀,露出GaN材料;
9)生长二极管的阳极金属,阳极金属直接接触底部的GaN材料形成肖特基接触,且由于 阳极金属直接接触GaN,其导通电压能够从传统AlGaN基二极管的1.12V下降到0.6V;而 由于阳极金属在侧面和AlGaN/GaN界面的二维电子气直接接触,因此器件的正向导通电阻也 会明显下降。二极管的阳极金属同时覆盖在MIS-HEMT器件源极的欧姆接触上,而阴极则与 MIS-HEMT器件漏极共用一个电极,在步骤6中制备漏端欧姆接触金属时,二极管的阴极金 属也同时被制作得到,GaN肖特基二极管与MIS-HEMT器件形成并联结构;
10)生长介质层,作为MIS-HEMT器件栅和二极管阳极之间的隔离层;
11)制作MIS-HEMT器件栅金属;
12)对金属电极进行开孔,最终完成MIS-HEMT器件和GaN肖特基二极管的集成。
上述制备方法中,所述步骤5)具体为,ALD生长3~5nm的AlN层,LPCVD生长20~30nm 的SiN层作为栅介质。
上述制备方法中,所述步骤6)具体为,光刻露出欧姆接触部分,采用ICP刻蚀该区域 的SiN介质层,并腐蚀AlN层,随后电子束蒸发生长金属叠层,剥离后在欧姆接触的位置留 下金属叠层,紧接着在快速退火形成欧姆接触,所述金属叠层为Ti/Al/Ni/Au。
上述制备方法中,所述步骤8)具体为,光刻露出二极管阳极,而GaN MIS-HEMT部分则由光刻胶覆盖,采用ICP刻蚀二极管阳极的SiN介质层,再采用5:1BOE腐蚀阳极的AlN 层,使得二极管阳极的GaN层裸露在外。或者,光刻露出二极管的阳极部分,而MIS-HEMT 部分则由光刻胶覆盖,采用ICP刻蚀阳极的SiN介质层,再采用5:1BOE腐蚀阳极的AlN层, 使得阳极的GaN层裸露在外,并保留二极管阳极的凹槽边缘的介质层。
上述制备方法中,所述步骤9)具体为,光刻露出二极管阳极区域需要生长阳极金属的 部分,而GaN MIS-HEMT区域仍由光刻胶保护,电子束蒸发生长阳极金属,剥离后的金属在 二极管阳极部分与GaN接触形成肖特基接触,同时阳极金属覆盖在源极欧姆接触上,形成电 学接触。或者,光刻露出二极管阳极需要长金属的部分,而MIS-HEMT区域仍由光刻胶保护, 电子束蒸发生长阳极金属,剥离后的金属在二极管阳极部分与GaN直接接触形成肖特基接触, 同时阳极金属覆盖在MIS-HEMT源极欧姆接触上,以及覆盖在二极管阳极的凹槽边缘的介质 层上并延伸到有源区表面的介质上,形成MIS场版结构。
上述制备方法中,所述步骤10)具体为,ALD生长20~25nm的Al2O3
本发明进一步提供了一种双向导电单极单向开关,其特征在于,包括GaN肖特基二极管 和MIS-HEMT器件,MIS-HEMT器件和GaN肖特基二极管在器件宽度方向上进行交叉设置, 形成叉指并联结构MIS-HEMT器件由源极、栅极和漏极组成,栅下形成凹槽结构,为GaN增强型凹槽MIS-HEMT器件,该器件栅下的AlGaN层被完全刻蚀,在凹槽区域生长有介质 层,源端和漏端的金属叠层与AlGaN材料形成欧姆接触;GaN肖特基二极管由阳极和阴极 组成,二极管的阳极采用凹槽结构,阳极金属直接接触底部的GaN材料形成肖特基接触,GaN 肖特基二极管的阳极和MIS-HEMT器件源极通过金属连接,且GaN肖特基二极管与 MIS-HEMT器件栅极之间采用介质层隔离,GaN肖特基二极管的阴极与MIS-HEMT器件的 漏极共用一个电极,GaN肖特基二极管与MIS-HEMT器件形成并联结构。
所述GaN肖特基二极管的阳极凹槽边缘的介质层未被刻蚀,GaN肖特基二极管的阳极 金属除了覆盖在整个凹槽结构之上,还有部分延申到有源区,并在凹槽边缘以及有源区部分 与介质层和半导体形成MIS结构。
本发明的技术效果:
1、高温氧化腐蚀工艺没有引入等离子体,因此不会在GaN MIS-HEMT器件以及GaN肖 特基二极管器件凹槽中引入损伤;
2、高温氧化腐蚀工艺具有自停止的特性,能够实现器件之间的高度统一性;
3、由于GaN MIS-HEMT器件的凹槽和GaN肖特基二极管的凹槽在同一工艺中进行,因 此没有增加工艺的复杂性;
4、与现有的GaN基开关器件相比,该工艺能够实现具有正向阈值电压、更高正、反向 导通电流以及低反向开启电压的开关器件,实现更低的开关损耗、更小的占用面积以及更高 的转换速率。
附图说明
图1为本发明集成GaN增强型凹槽结构MIS-HEMT器件和GaN肖特基二极管的双向导电单极单向开关的俯视图;
图2为本发明GaN增强型凹槽结构MIS-HEMT器件部分的剖面图;
图3(a)为本发明GaN肖特基二极管部分的剖面图;
图3(b)为本发明带有MIS场版结构的GaN肖特基二极管部分的剖面图;
图4为Si衬底上生长的GaN帽层/AlGaN/GaN外延片;
图5为刻蚀栅下GaN帽层的过程;
图6为氧化腐蚀形成凹槽结构的过程;
图7为生长介质层的过程;
图8为制备欧姆接触的过程;
图9为离子注入形成隔离的过程;
图10(a)为二极管区阳极部分介质刻蚀的过程;
图10(b)为带场版结构的二极管区阳极部分介质刻蚀的过程;
图11(a)为二极管区生长阳极金属的过程;
图11(b)为带场版的二极管区生长阳极金属的过程;
图12(a)为GaN MIS-HEMT部分生长介质层的过程;
图12(b)为GaN肖特基二极管部分生长介质层的过程;
图12(c)为带场版的GaN肖特基二极管部分生长介质层的过程;
图13(a)为GaN MIS-HEMT部分制作栅金属的过程;
图13(b)为制作完栅金属后GaN肖特基二极管部分的剖面图;
图13(c)为制作完栅金属后带场版的GaN肖特基二极管部分的剖面图;
图中,1—硅衬底;2—氮化镓缓冲层;3—铝镓氮势垒层;4—氮化镓帽层;5—欧姆接触 金属叠层;6—介质层1;7—介质层2;8—介质层3;9—栅金属叠层;10—阳极金属叠层。
具体实施方式
以下结合附图,通过具体的实施例子对本发明所述的集成GaN增强型凹槽结构MIS-HEMT器件和GaN肖特基二极管制备的双向导电单极单向开关实施方法做进一步的说明
本发明集成MIS-HEMT和GaN肖特基二极管的方法制备的双向导电单极单向开关,如 图1所示。该器件采用GaN增强型凹槽MIS-HEMT器件,该GaN增强型凹槽MIS-HEMT 器件和GaN肖特基二极管在器件宽度方向上进行交叉设置,形成叉指并联结构。对图1器件 俯视图沿着A1-A2直线做剖面,得到如图2所示的GaN增强型凹槽MIS-HEMT器件部分的 剖面图,该器件由源极、栅极和漏极组成,栅下形成凹槽结构,即栅下的AlGaN层被完全刻 蚀,导致栅下无二维电子气,因此可以实现增强型的特性,同时在凹槽区域生长有介质层, 以减小栅的漏电并提高栅击穿电压,源端和漏端的金属叠层通过高温退火工艺与AlGaN材料 形成欧姆接触;沿着图1俯视图中B1-B2方向做剖面,得到GaN肖特基二极管部分的剖面图 如图3所示,该器件由阳极和阴极组成,二极管的阳极采用凹槽结构,即刻蚀阳极区域的 AlGaN层形成凹槽,生长的阳极金属Ni/Au会直接接触底部的GaN材料形成肖特基接触,由 于Ni金属与GaN之间的势垒高度低于Ni金属与AlGaN之间的势垒高度,且Ni金属可以直 接接触沟道内的二维电子气,因此能够显著降低导通电压和导通电阻。其中,图3(a)为凹槽 内介质层完全刻蚀的普通二极管结构;而图3(b)则为带MIS场版结构的肖特基二极管,即凹 槽边缘的介质层未被刻蚀,阳极金属除了覆盖在整个凹槽结构之上,还有部分延申到有源区, 并在凹槽边缘以及有源区部分与介质层和半导体形成MIS结构的场版,该结构能够缓解阳极 边缘的高电场,并显著提升肖特基二极管的击穿电压,因而提升整个器件的击穿电压。二极管的阳极和MIS-HEMT器件源极通过金属连接,且GAN肖特基二极管与MIS-HEMT器件栅 极之间采用介质层隔离,二极管的阴极与MIS-HEMT器件的漏极共用一个电极,两者形成并 联结构。当MIS-HEMT器件栅端电压大于阈值电压,MIS-HEMT器件漏端电压为正时,GaN MIS-HEMT器件开启并正向导通,为电流提供正向通路;当MIS-HEMT器件栅上电压为零, 且电路中存在反向电流时,GaN-MISHEMT器件关断,而与其叉指并联的二极管正向导通, 为电路提供反向续流通路,防止因GaN基MIS-HEMT器件突然关断而引入的电压尖刺。
图4到13为制备本发明集成GaN增强型凹槽结构MIS-HEMT器件和GaN肖特基二极管的双向导电单极单向开关的主要工艺步骤.
具体实施例一:
1)外延片是Si衬底上生长的带有GaN帽层的AlGaN/GaN异质结结构,AlGaN/GaN外延片的具体结构及厚度为2.5nm GaN/25nm AlGaN/420nm i-GaN/4.2um buffer/1000umSi,外延 层的厚度视实际工艺而定,没有严格限制,如图4所示,
2)首先采用干法刻蚀技术刻蚀MIS-HEMT器件栅下及二极管阳极区的GaN帽层,露出 AlGaN层,如图5所示,未刻蚀区域的GaN帽层作为氧化腐蚀的掩膜层;
3)将外延片放置于620~680℃的高温退火炉中,通入氧气氧化40~60分钟,在该温度下, GaN材料无法被氧化,而AlGaN材料则很容易被氧化,因此只有MIS-HEMT器件栅下及二 极管阳极露出的AlGaN层被完全氧化;
4)将氧化后的外延片放置于70~80℃的TMAH或KOH液体中腐蚀50~70分钟,将MIS-HEMT器件栅下及二极管阳极被氧化的AlGaN层完全腐蚀掉,同时形成GaN凹槽HEMT 器件的栅极和GaN凹槽GAN肖特基二极管器件的阳极。由于只有AlGaN层被氧化,因此腐 蚀会自停止在GaN层,形成光滑的表面,如图6所示;
5)ALD生长5nm的AlN层,LPCVD生长20nm的SiN层作为栅介质,如图7所示;
6)光刻露出欧姆接触部分,采用ICP刻蚀该区域的SiN介质、5:1BOE腐蚀AlN层,随后电子束蒸发生长Ti/Al/Ni/Au,剥离后在欧姆接触的位置留下金属叠层,紧接着在860℃的 快速退火炉中退火33s形成欧姆接触,如图8所示;
7)再次光刻露出非器件部分,采用高能F离子注入破坏非器件部分的晶格,在器件之间 形成电学隔离,注入角度为7°,三次注入的能量和计量分别为150keV、3e14 cm-3,80keV、 1e14 cm-3,40keV、6e13 cm-3,如图9所示;
8)第三次光刻只露出二极管的阳极部分,而GaN MIS-HEMT部分则由光刻胶覆盖,采 用ICP刻蚀阳极的SiN介质层,再采用5:1BOE腐蚀阳极的AlN层,使得阳极的GaN层裸 露在外,如图10(a)所示;
9)第四次光刻只露出二极管阳极需要长金属的部分,而GaN MIS-HEMT区域仍由光刻 胶保护,电子束蒸发生长阳极金属Ni/Au,剥离后的金属在二极管阳极部分与GaN直接接触 形成肖特基接触,由于Ni金属直接与GaN材料接触,二极管的正向导通电压从传统的AlGaN 基二极管的1.12V下降到0.6V,同时阳极金属覆盖在源极欧姆接触上,形成电学接触,如图 11(a)所示;
10)ALD生长20nm的Al2O3,作为二极管阳极和MIS-HEMT器件栅极之间的隔离层,GaNMIS-HEMT部分如图12(a)所示,GaN肖特基二极管部分如图12(b)所示;
11)电子束蒸发生长Ni/Au,并剥离形成栅金属,GaN-MISHEMT部分形成凹槽栅结构, 如图13(a)所示,GaN肖特基二极管部分的阳极金属则和栅极金属用介质层隔离,如图13(b) 所示;
12)对欧姆接触电极部分的Al2O3采用5:1BOE开孔,最终形成本文发明所描述的叉指 型开关器件,其俯视图如图1所示,其中GaN-MISHEMT部分如图2所示,GaN肖特基二极 管部分如图3(b)所示。
具体实施例二:
1)外延片是Si衬底上生长的带有GaN帽层的AlGaN/GaN异质结结构,AlGaN/GaN外延片的具体结构及厚度为2.5nm GaN/25nm AlGaN/420nm i-GaN/4.2um buffer/1000umSi,外延 层的厚度视实际工艺而定,没有严格限制,如图4所示,
2)首先采用干法刻蚀技术刻蚀MIS-HEMT器件栅下及二极管阳极区的GaN帽层,露出 AlGaN层,如图5所示,未刻蚀区域的GaN帽层作为氧化腐蚀的掩膜层;
3)将外延片放置于620~680℃的高温退火炉中,通入氧气氧化40~60分钟,在该温度下, GaN材料无法被氧化,而AlGaN材料则很容易被氧化,因此只有MIS-HEMT器件栅下及二 极管阳极露出的AlGaN层被完全氧化;
4)将氧化后的外延片放置于70~80℃的TMAH或KOH液体中腐蚀50~70分钟,将MIS-HEMT器件栅下及二极管阳极被氧化的AlGaN层完全腐蚀掉,同时形成GaN凹槽HEMT 器件的栅极和GaN凹槽GAN肖特基二极管器件的阳极。由于只有AlGaN层被氧化,因此腐 蚀会自停止在GaN层,形成光滑的表面,如图6所示;
5)ALD生长5nm的AlN层,LPCVD生长20nm的SiN层作为栅介质,如图7所示;
6)光刻露出欧姆接触部分,采用ICP刻蚀该区域的SiN介质、5:1BOE腐蚀AlN层,随后电子束蒸发生长Ti/Al/Ni/Au,剥离后在欧姆接触的位置留下金属叠层,紧接着在860℃的 快速退火炉中退火33s形成欧姆接触,如图8所示;
7)再次光刻露出非器件部分,采用高能F离子注入破坏非器件部分的晶格,在器件之间 形成电学隔离,注入角度为7°,三次注入的能量和计量分别为150keV、3e14 cm-3,80keV、 1e14 cm-3,40keV、6e13 cm-3,如图9所示;
8)第三次光刻只露出二极管的阳极部分,而GaN MIS-HEMT部分则由光刻胶覆盖,采 用ICP刻蚀阳极的SiN介质层,再采用5:1BOE腐蚀阳极的AlN层,使得阳极的GaN层裸 露在外,凹槽边缘部分的介质层没有被刻蚀,作为后续工艺中场版结构的重要组成部分,如图10(b)所示;
9)第四次光刻只露出二极管阳极需要长金属的部分,而GaN MIS-HEMT区域仍由光刻 胶保护,电子束蒸发生长阳极金属Ni/Au,剥离后的金属在二极管阳极部分与GaN直接接触 形成肖特基接触,由于Ni金属直接与GaN材料接触,二极管的正向导通电压从传统的AlGaN 基二极管的1.12V下降到0.6V,同时阳极金属覆盖在源极欧姆接触上,形成电学接触,阳极 金属覆盖在凹槽边缘的栅介质上并延伸到有源区表面的介质上,形成MIS场版结构,该结构 能够缓和阳极边缘的高电场,是的器件的击穿电压得到提升,如图11(b)所示;
10)ALD生长20nm的Al2O3,作为二极管阳极和MIS-HEMT器件栅极之间的隔离层,GaNMIS-HEMT部分如图12(a)所示,带场版的GaN肖特基二极管部分如图12(c)所示;
11)电子束蒸发生长Ni/Au,并剥离形成栅金属,GaN-MISHEMT部分形成凹槽栅结构, 如图13(a)所示,带场版的GaN肖特基二极管部分的阳极金属则和栅极金属用介质层隔离, 如图13(c)所示;
12)对欧姆接触电极部分的Al2O3采用5:1BOE开孔,最终形成本文发明所描述的叉指 型开关器件,其俯视图如图1所示,其中GaN-MISHEMT部分如图2所示,带场版的GaN 肖特基二极管部分如图3(b)所示。
虽然本发明已以较佳实施例披露如上,然而并非用以限定本发明。任何熟悉本领域的技 术人员,在不脱离本发明技术方案范围情况下,都可利用上述揭示的方法和技术内容对本发 明技术方案作出许多可能的变动和修饰,或修改为等同变化的等效实施例。因此,凡是未脱 离本发明技术方案的内容,依据本发明的技术实质对以上实施例所做的任何简单修改、等同 变化及修饰,均仍属于本发明技术方案保护的范围内。

Claims (10)

1.一种集成MIS-HEMT器件和GaN肖特基二极管的方法,其特征在于,包括以下步骤:
1)外延片准备:Si衬底上通过MOCVD技术生长的带有GaN帽层的AlGaN/GaN异质结结构;
2)采用干法刻蚀技术刻蚀MIS-HEMT器件栅下及二极管阳极区的GaN帽层,露出AlGaN层,未刻蚀区域的GaN帽层作为氧化腐蚀的掩膜层;
3)将外延片放置于620~680℃的高温氧化炉中,通入氧气氧化40~60分钟,在该温度下,GaN材料无法被氧化,而AlGaN材料则很容易被氧化,因此MIS-HEMT器件栅下及二极管阳极未被GaN帽层覆盖的区域的AlGaN材料被完全氧化;
4)将氧化后的外延片放置于70~80℃的TMAH或KOH液体中腐蚀50~70分钟,使得MIS-HEMT器件栅下及二极管阳极被氧化的AlGaN层完全腐蚀掉,MIS-HEMT器件栅下形成凹槽结构,同时二极管阳极也形成凹槽结构;
5)生长栅介质层;
6)在MIS-HEMT器件的源端和漏端区域制作欧姆接触金属,其中,漏端的欧姆接触金属同时也是二极管的阴极金属;
7)通过F离子注入的手段破坏非器件部分的晶格,形成电学隔离;
8)对二极管阳极部分的介质层进行刻蚀,露出GaN材料;
9)生长二极管的阳极金属,阳极金属直接接触底部的GaN材料形成肖特基接触,二极管的阳极金属同时覆盖在MIS-HEMT器件源极的欧姆接触上,而二极管的阴极则与MIS-HEMT器件漏极共用一个电极,构成GaN肖特基二极管与MIS-HEMT器件并联结构;
10)生长介质层,作为MIS-HEMT器件栅和二极管阳极之间的隔离层;
11)制作MIS-HEMT器件栅金属;
12)对金属电极进行开孔,最终完成MIS-HEMT器件和GaN肖特基二极管的集成。
2.如权利要求1所述的方法,其特征在于,所述步骤5)具体为,ALD生长3~5nm的AlN层,LPCVD生长20~30nm的SiN层作为栅介质。
3.如权利要求1所述的方法,其特征在于,所述步骤6)具体为,光刻露出欧姆接触部分,采用ICP刻蚀该区域的SiN介质层,并腐蚀AlN层,随后电子束蒸发生长金属叠层,剥离后在欧姆接触的位置留下金属叠层,紧接着在快速退火形成欧姆接触。
4.如权利要求1所述的方法,其特征在于,所述步骤8)具体为,光刻露出二极管的阳极部分,而MIS-HEMT部分则由光刻胶覆盖,采用ICP刻蚀二极管阳极的SiN介质层,再采用5:1BOE腐蚀阳极的AlN层,使得二极管阳极的GaN层裸露在外。
5.如权利要求4所述的方法,其特征在于,所述步骤9)具体为,光刻露出二极管阳极区域需要生长阳极金属的部分,而MIS-HEMT区域仍由光刻胶保护,电子束蒸发生长阳极金属,剥离后的金属在二极管阳极部分与GaN接触形成肖特基接触,同时阳极金属覆盖在MIS-HEMT源极欧姆接触上,形成电学接触。
6.如权利要求1所述的方法,其特征在于,所述步骤8)具体为,光刻露出二极管的阳极部分,而MIS-HEMT部分则由光刻胶覆盖,采用ICP刻蚀阳极的SiN介质层,再采用5:1BOE腐蚀阳极的AlN层,使得阳极的GaN层裸露在外,并保留二极管阳极的凹槽边缘的介质层。
7.如权利要求6所述的方法,其特征在于,所述步骤9)具体为,光刻露出二极管阳极需要长金属的部分,而MIS-HEMT区域仍由光刻胶保护,电子束蒸发生长阳极金属,剥离后的金属在二极管阳极部分与GaN直接接触形成肖特基接触,同时阳极金属覆盖在MIS-HEMT源极欧姆接触上,以及覆盖在二极管阳极的凹槽边缘的介质层上并延伸到有源区表面的介质上,形成MIS场版结构。
8.如权利要求1所述的方法,其特征在于,所述步骤10)具体为,ALD生长20~25nm的Al2O3
9.一种采用权利要求1所述方法制备的双向导电单极单向开关,其特征在于,MIS-HEMT器件和GaN肖特基二极管在器件宽度方向上进行交叉设置,其中MIS-HEMT器件由源极、栅极和漏极组成,栅下形成凹槽结构,该器件栅下的AlGaN层被完全刻蚀,在凹槽区域生长有介质层,源端和漏端的金属叠层与AlGaN材料形成欧姆接触;GaN肖特基二极管由阳极和阴极组成,GaN肖特基二极管的阳极采用凹槽结构,阳极金属直接接触底部的GaN材料形成肖特基接触,GaN肖特基二极管的阳极和MIS-HEMT器件源极通过金属连接,且GaN肖特基二极管与MIS-HEMT器件栅极之间采用介质层隔离,GaN肖特基二极管的阴极与MIS-HEMT器件的漏极共用一个电极,MIS-HEMT器件和GaN肖特基二极管形成并联结构。
10.如权利要求9所述的方法制备的双向导电单极单向开关,其特征在于,所述GaN肖特基二极管的阳极凹槽边缘的介质层未被刻蚀,GaN肖特基二极管的阳极金属除了覆盖在整个凹槽结构之上,还有部分延申到有源区,并在凹槽边缘以及有源区部分与介质层和半导体形成MIS场版结构。
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Publication number Priority date Publication date Assignee Title
CN117276335A (zh) * 2023-11-20 2023-12-22 南京大学 一种具有解耦合反向导通能力的增强型GaN HEMT及其制作方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130087803A1 (en) * 2011-10-06 2013-04-11 Epowersoft, Inc. Monolithically integrated hemt and schottky diode
CN103579332A (zh) * 2013-10-31 2014-02-12 中航(重庆)微电子有限公司 异质结场效应管及其制作方法
CN103745992A (zh) * 2014-01-22 2014-04-23 西安电子科技大学 基于复合漏极的AlGaN/GaN MISHEMT高压器件及其制作方法
US8946724B1 (en) * 2010-06-02 2015-02-03 Hrl Laboratories, Llc Monolithically integrated self-aligned GaN-HEMTs and Schottky diodes and method of fabricating the same
CN106159671A (zh) * 2015-04-10 2016-11-23 中国科学院苏州纳米技术与纳米仿生研究所 Ⅲ族氮化物HEMT与GaN激光器的集成单片及其制作方法
CN111613671A (zh) * 2020-06-02 2020-09-01 华南师范大学 一种对称结构的GaN基MIS-HEMT器件及其制备方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8946724B1 (en) * 2010-06-02 2015-02-03 Hrl Laboratories, Llc Monolithically integrated self-aligned GaN-HEMTs and Schottky diodes and method of fabricating the same
US20130087803A1 (en) * 2011-10-06 2013-04-11 Epowersoft, Inc. Monolithically integrated hemt and schottky diode
CN103579332A (zh) * 2013-10-31 2014-02-12 中航(重庆)微电子有限公司 异质结场效应管及其制作方法
CN103745992A (zh) * 2014-01-22 2014-04-23 西安电子科技大学 基于复合漏极的AlGaN/GaN MISHEMT高压器件及其制作方法
CN106159671A (zh) * 2015-04-10 2016-11-23 中国科学院苏州纳米技术与纳米仿生研究所 Ⅲ族氮化物HEMT与GaN激光器的集成单片及其制作方法
CN111613671A (zh) * 2020-06-02 2020-09-01 华南师范大学 一种对称结构的GaN基MIS-HEMT器件及其制备方法

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117276335A (zh) * 2023-11-20 2023-12-22 南京大学 一种具有解耦合反向导通能力的增强型GaN HEMT及其制作方法
CN117276335B (zh) * 2023-11-20 2024-02-09 南京大学 一种具有解耦合反向导通能力的增强型GaN HEMT及其制作方法

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