FR2656740A1 - SEMICONDUCTOR WITH JUNCTION COMPRISING A HETEROJUNCTION STRUCTURE. - Google Patents

SEMICONDUCTOR WITH JUNCTION COMPRISING A HETEROJUNCTION STRUCTURE. Download PDF

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FR2656740A1
FR2656740A1 FR9003009A FR9003009A FR2656740A1 FR 2656740 A1 FR2656740 A1 FR 2656740A1 FR 9003009 A FR9003009 A FR 9003009A FR 9003009 A FR9003009 A FR 9003009A FR 2656740 A1 FR2656740 A1 FR 2656740A1
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aun
layer
dno
gaas
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Nam Chun-Woo
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Samsung Electronics Co Ltd
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Samsung Electronics Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor 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
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/06—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor 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
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
    • H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227—Multistep 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
    • H01L29/66409—Unipolar field-effect transistors
    • H01L29/66431—Unipolar field-effect transistors with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor 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
    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/06—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions
    • H01L29/08—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions with semiconductor regions connected to an electrode carrying current to be rectified, amplified or switched and such electrode being part of a semiconductor device which comprises three or more electrodes
    • H01L29/0843—Source or drain regions of field-effect devices
    • H01L29/0891—Source or drain regions of field-effect devices of field-effect transistors with Schottky gate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor 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
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
    • H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227—Multistep 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
    • H01L29/66409—Unipolar field-effect transistors
    • H01L29/66446—Unipolar field-effect transistors with an active layer made of a group 13/15 material, e.g. group 13/15 velocity modulation transistor [VMT], group 13/15 negative resistance FET [NERFET]
    • H01L29/66462—Unipolar field-effect transistors with an active layer made of a group 13/15 material, e.g. group 13/15 velocity modulation transistor [VMT], group 13/15 negative resistance FET [NERFET] with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00—Semiconductor 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
    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68—Types 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
    • H01L29/76—Unipolar devices, e.g. field effect transistors
    • H01L29/772—Field effect transistors
    • H01L29/778—Field effect transistors with two-dimensional charge carrier gas channel, e.g. HEMT ; with two-dimensional charge-carrier layer formed at a heterojunction interface
    • H01L29/7786—Field effect transistors with two-dimensional charge carrier gas channel, e.g. HEMT ; with two-dimensional charge-carrier layer formed at a heterojunction interface with direct single heterostructure, i.e. with wide bandgap layer formed on top of active layer, e.g. direct single heterostructure MIS-like HEMT
    • H01L29/7787—Field effect transistors with two-dimensional charge carrier gas channel, e.g. HEMT ; with two-dimensional charge-carrier layer formed at a heterojunction interface with direct single heterostructure, i.e. with wide bandgap layer formed on top of active layer, e.g. direct single heterostructure MIS-like HEMT with wide bandgap charge-carrier supplying layer, e.g. direct single heterostructure MODFET

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  • Condensed Matter Physics & Semiconductors (AREA)
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  • Computer Hardware Design (AREA)
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  • Junction Field-Effect Transistors (AREA)
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Abstract

Il est créé un dispositif de semi-conducteur à jonction et son procédé de fabrication qui présente une caractéristique de haute mobilité des électrons due à une structure à hétérojonction. Le dispositif de semi-conducteur à jonction présente une nouvelle structure qui peut diminuer une résistance de source en amenant directement des couches de recouvrement (19) en contact avec une couche d'électron bi-dimensionnel. Pour réaliser ce but, le dispositif de semi-conducteur à jonction comprend une première couche tampon conductrice (13), des première et seconde couches de recouvrement (19) d'un premier type de conduction, des première et seconde électrodes de courant (21, 23), une couche d'écartement (15), une première couche de source (17) conductrice et une électrode de commande (25).There is created a junction semiconductor device and its manufacturing process which exhibits a characteristic of high mobility of electrons due to heterojunction structure. The junction semiconductor device has a novel structure which can decrease source resistance by directly bringing cover layers (19) into contact with a two-dimensional electron layer. To achieve this object, the junction semiconductor device comprises a first conductive buffer layer (13), first and second cover layers (19) of a first conduction type, first and second current electrodes (21 , 23), a spacer layer (15), a first conductive source layer (17) and a control electrode (25).

Description

La présente invention concerne un dispositif de semi-The present invention relates to a semiconductor device

conducteur à jonction et son procédé de fabrication et, en particulier, un dispositif de semi-conducteur à jonction et un procédé de fabrication pour un dispositif de semi-conducteur à jonction présentant une caractéristique de haute mobilité des électrons due à une  junction conductor and its method of manufacture and, in particular, a junction semiconductor device and a manufacturing method for a junction semiconductor device having a characteristic of high electron mobility due to a

structure à hétérojonction.heterojunction structure.

D'une manière récente, en rapport avec une progression rapide vers une société privilégiant l'information et la communication, le besoin d'un ordinateur à ultrahaute vitesse, d'une ultrahaute fréquence et d'une communication de fibre optique sont  Recently, in relation to a rapid progression towards an information and communication-oriented society, the need for an ultra-high-speed, ultra-high-frequency computer and fiber optic communication is

encore renforcées.further strengthened.

Le dispositif utilisant le Si antérieur ayant toutefois trouvé des limitations dans son aptitude à  The device using the prior Si, however, having found limitations in its ability to

satisfaire ce besoin, une étude axée sur les semi-  meeting this need, a semi-

conducteurs à jonction dont les caractéristiques  junction conductors whose characteristics

importantes soient b'onnesa été activement menée.  important have been actively pursued.

Parmi les semi-conducteurs à jonction, le Ga As ,5} présentant les caractéristiques d'une haute mobilité des électrons, d'une vitesse élevée des électrons et une semi-isolatione celui-ci offre les avantages d'une haute efficacité, d'une haute fréquence, d'un faible niveau de bruit et d'une faible consommation de puissance électrique, etc, en regard des  Among the junction semiconductors, the Ga As, 5} exhibiting the characteristics of a high electron mobility, a high electron velocity and a semi-isolation it offers the advantages of a high efficiency, a high frequency, a low noise level and a low power consumption, etc., with regard to

caractéristiques de Si.characteristics of Si.

Ainsi, en utilisant les bonnes caractéristiques du Sa As, des recherches concernant la fabrication d'un circuit d'hyperfréquence monolithique à faible niveau de bruit et d'un circuit digital d'ultrahaute vitesse à faible consommation de puissance électrique ont été  Thus, by using the good characteristics of Sa As, research on the manufacture of a low-noise monolithic microwave circuit and an ultrahigh-speed digital circuit with low power consumption has been carried out.

activement menées.actively conducted.

Parmi ces dispositifs, un transistor à haute mobilité des électrons (désigné ci-après par "HEMT") présentant les caractéristiques de faible niveau de bruit, haute fréquence et vitesse élevée est commandé par l'effet de  Among these devices, a high electron mobility transistor (hereinafter referred to as "HEMT") having the characteristics of low noise level, high frequency and high speed is controlled by the effect of

champ électrique utilisant un électron modulé.  electric field using a modulated electron.

C'est-à-dire que le transistor du type HEMT présente  That is, the HEMT type transistor has

une structure de croissance d'une couche de Ga As N-  a growth structure of a layer of GaAs N-

d'une couche de Al Ga As et d'une couche de Al Ga As N+  a layer of Al GaAs and a layer of Al GaAs N +

prenant la forme continue d'un mince film.  taking the continuous form of a thin film.

Ensuite, un électron,qui devient une source de courant, est généré à partir de la couche de source Al Ga As N+,n'existe pas avec un donneur désionisé ou une impureté,mais est commandé par l'effet de champ électrique d G à la formation d'une haute concentration entre la couche tampon Ga As N et la couche d'écartement  Then, an electron, which becomes a current source, is generated from the Al GaAs N + source layer, does not exist with a deionized donor or impurity, but is controlled by the electric field effect d G the formation of a high concentration between the GaAs N buffer layer and the spacer layer

Al Ga As.Al Ga As.

Le Si est habituellement utilisé comme matériau  Si is usually used as a material

dopant de la couche de source Al Ga As N+.  dopant of the Al GaAs N + source layer.

Les caractéristiques de faible niveau de bruit et de haute fréquence du transistor du type HEMT sont d'autant plus améliorées qu'une transconductance gm devient plus grande Ensuite, du fait que la transductance est accrue dans la mesure de la diminution d'une résistance de sources il est important de réduire la résistance de source. La figure 1 est une vue en coupe représentant une  The low noise and high frequency characteristics of the HEMT type transistor are all the more improved if a transconductance gm becomes larger. Secondly, because the transductance is increased to the extent that the resistance of the transistor is reduced. sources it is important to reduce the source resistance. FIG. 1 is a sectional view showing a

structure générale d'un transistor du type HEMT.  general structure of a transistor type HEMT.

A la figure 1, une couche tampon de Ga As N 2, une couche d'écartement Al Ga As 3 et une couche de source Al Ea As N+ 4 sont formées sur la surface entière d'un  In FIG. 1, a Ga As N 2 buffer layer, an Al Ga As 3 spacer layer and an Al Ea As N + 4 source layer are formed on the entire surface of a

substrat Ga As semi-isolant 1.GaAs semi-insulating substrate 1.

Une électrode de grille 8 est formée dans la région -30 prescrite de la surface exposée de la couche de source Al Ga As N+ 4 et une électrode de source et de drain 6, 7 sont formées en interposant une couche de recouvrement Ga As N+ 5 dans la région supérieure d'une couche de  A gate electrode 8 is formed in the prescribed region -30 of the exposed surface of the Al GaAs N + source layer 4 and a source and drain electrode 6, 7 are formed by interposing a GaAs N + 5 overlay layer. in the upper region of a layer of

source Al Ga As N+ 4 à l'exception de la région prescrite.  source Al Ga As N + 4 with the exception of the prescribed region.

zrt L'électrode de source et l'électrode de drain 6, 7 suep 55 e 9 WJ oa uos = +N s Ieg 4 uawa J Ano Da ap aqnno D aun S a u: t +N Sve 9 Ii am Dnos ap a 4 qnon apun efú s Uegl I 1 quawa U J Spoe Dop a 4 mnom aun e _h N s We 9 ap uodweq Lq 4 no D eun -sjde-1 J nbz Idxa Suawa^a F q 1 sa IWBH adÀ nip Josisue J nrip uo T;et Jqei ap gpgmo Jd un -anb T 4 uapr a z Jed aun arnbib 4 uep uori Isodwo: aun 02  zrt The source electrode and the drain electrode 6, 7 suep 55 e 9 WJ oa uos = + N s Ieg 4 uawa J Ano Da ap aqnno D aun S au: t + N Sve 9 Ii am Dnos ap a 4 qNo APUN UFE s Uegl I 1 quawa UJ Spoe Dop 4 MNom aun _h e s N ap 9 We uodweq Lq 4 no eun -sjde D-1 J nbz iDXA Suawa a F ^ q 1 IWBH its ADA nip Josisue J NRIP uo T and Jqei ap gpgmo Jd a -anb T 4 uapr az Jed aun aribib 4 uep uori Isodwo: aun 02

a 4 uassda J anbr 4 uap a Duas I+i J ap oiewnu un:a I aini F-  a 4 uassda J anbr 4 uap a Duas I + i J ap oiewnu a: a I aini F-

el ap ain 4 N 4 S aun V 6 anb Tuoit uoze 4 ueldwi uoi 5 g saun que 4 norie us aewjo F 4 ss Z s ani 6 el sp sain 4 mnss el =-ags Tsiegi q e anbtuoi uo eue Ildwil linbalsi Jns Jnaz Que 1 i W 3 H adÀq np jo 4 sisue i unp a Jn Dnis,Z el quequesg Jda J adno D ua an A aun S sa u a Jn 5 Oz el -D Jinos ap a Duevsise el Jinu Tw p ap que 4 aw Jad anb Tuo uoize 4 ueldw '1 i W 3 H adÀ np o 045 ssu:A un aar O aa 'e fawvlqo D d am ap u Os Te J u 3 t; oz +N s Veg I as D Jnos ap as 4 noz el ap e 2 s Vegt I uawa I Je I Sp asq Dno D e I ap aleqo-l S Duess S aun Z _ N s Ve L ap uodwv 4 aqmnom el Sa Q s IJ S 19 f 4 uawaq Je 3 ep a 4 Dno D el et +N s Veg I a D Jnos Sp a Sqno D el ada us o TI Jzeq sp;E ue Ssts> aunrp agnl T;suo D qsa inb a Djnos ap a Due 4 sisi aun s S V sanp amuanbj arineq 4 ap sainail+u T sunb s T Dse Je sap:a nea A Tu alq Tes ap Tin-q ap sa D Jo T-p Qw sanbi; sii 4 Deie D sap sio+asno; a 4 uaseid T ain 5 bi+ el V quasjdda D îe Jeu 95 1 i W 3 H ad 4 nrp J Os Tsus Li; un -a Dez J-iauip jlaiuasod ap sqrnd un suep i au Tjuoo us;e aeldip as I Suuolsuw Tp-Tq uo-daji un lrlanbel suep uo T;e^;ep a Smno D awwo D aqsl Tqrn sa Z _N se 59 ap uodwe 4 amqno D e I a et +N s Ve 9 IV an Jnos ap aqnnom el ap iqjed s snpod slauiuoisuaw Tp -Tq suo J 4 alg sep e 4 TI Tqow I ja uswrine a 4 sisuo Tnb g al OJ un snld ap anor i s Ve SIU 4 uawa Sje Dp aq Dno D el a Uuoisugwmp-Iq uo_ 4-ali un a J Qu 95 t +N s Ve 59 a Drnos ap a Dno D el ia q +N seg :uawa J Anoza J ap aqmno D el na Ae anbiw 4 o q De:uon un 4 uawio J 0 t V 999 Z l'ordre sur la surface d'un substrat Ga As semi- isclant t par la méthode d'épitaxie par faisceau moléculaire (désignée ci- après "MBE") ou par la méthode de déposition de vapeur organo-m étallique (désignée ci-après "MOCVD") Ensuite, une impureté telle que Si est implantée ioniquement à une certaine profondeur dans une partie de couche tampon 2 à l'exception d'une région de grille et une région d'implantation ionique 9 est formée par un processus de  el ain ap 4 N 4 S aun V 6 anb Tuoit uoze 4 ueldwi uoi 5 g saun that 4 norie us aewjo F 4 Z ss s ani 6 el sp healthy 4 MNSS el = -ags Tsiegi qe anbtuoi uo had Ildwil linbalsi Jns What Jnaz 1 i W 3 H adaq np jo 4 sisue i unp a Jn Dnis, Z el quequesg Jda J adno D ua an A au n S sa ua Jn 5 Oz el -D Jinos ap a Duevsise el Jinu Twp ap that 4 aw Jad anb Tuo uoize 4 ueldw '1 i W 3 H ada np o 045 ssu: Has a oo y ee dd am ap u Os Te J u 3 t; oz + N s Veg I as D Jnos ap ac 4 noz el ap e 2 s Vegt I uawa I I Spasq Dno D e D aleqo-l S Duess S aun Z _ N s Ve L ap uodwv 4 aqmnom el Sa Q s IJ S 19 f 4 uawaq I 3 ep a 4 Dno D el and + N s veg i a D Jnos Sp a Sqno D el ada us o TI Jzeq spe E ue Ssts> aunrp agnl T; suo D qsa inb a N os ap ap 4 4 san san san san san san san san san san san Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je Je ifi 4 Deie D sap sio + asno; a 4 uaseid T ain 5 bi + el V quasjdda D Thu 95 1 i W 3 H ad 4 nrp Y Os Tsus Li; a -a Dez J-iauip jlaiuasod ap sqrnd a Suep i au Tjuoo us e eeeldipas I Suuolsuw Tp-Tq uo-daji a lrlanbel suep uo T; e ^; ep a Smno D awwo D aqsl Tqrn sa Z _N se 59 ap uodwe 4 amqno D e I a and N s + Ve 9 IV year Jnos ap ap aqnnom el iqjed s snpod slauiuoisuaw Tp -tq suo J alg September 4 e 4 TI Tqow I ja uswrine 4 g Sisuo Tnb al OJ a SNLD ap anor is Ve SIU 4 uawa Sje Dp aq Dno D el Uuoisugwmp-Iq uo_ 4-ali a a J Q 95 t + N s Ve 59 a Drnos ap a Dno D el ia q + N seg: uawa J Anoza J ap aqmno The following describes the order on the surface of a GaAs semiselective substrate by the method of molecular beam epitaxy (hereinafter referred to as "the molecular beam epitaxy"). MBE ") or by the method of organometallic vapor deposition (hereinafter referred to as" MOCVD "). Next, an impurity such as Si is implanted ionically at a certain depth in a buffer layer portion 2 except for a gate region and an ion implantation region 9 is formed p ar a process of

recuit.annealing.

Une électrode de source et une électrode de drain 6, 7 sont ensuite formées sur la surface de la couche de  A source electrode and a drain electrode 6, 7 are then formed on the surface of the

recouvrement Ga As Ni 5.GaAs Ni 5 recovery.

Après ces opérations, en éliminant par photolithographie une couche de recouvrement Ea As Ns 5 de la région prescrite dans laquelle la région à implantation ionique 9 n'est pas formée, une couche de source Al Ga As N+ 4 èst exposée et une électrode de grille  After these operations, by photolithographically removing a cover layer Ea As Ns 5 from the prescribed region in which the ion-implanted region 9 is not formed, an Al GaAs N + 4 source layer is exposed and a gate electrode

a est formée.a is formed.

Une résistance de source d'un transistor du type HEMT formée de la manière décrite précédemment est diminuée en raison de la région à implantation ionique formée dans une partie de la couche de recouvrement Ga As N+ et de la couche de source Al Ba As N+, de la couche d'écartement Al Ga As et de la couche tampon de Ga As N dans la partie  A source resistor of a HEMT type transistor formed as previously described is decreased due to the ion implantation region formed in a portion of the GaAs N + cover layer and the Al BaAs N + source layer, of the Al GaAs spacer layer and the GaAs N buffer layer in the

inférieure de cette couche de recouvrement.  lower of this covering layer.

En raison de ce qu'un donneur ionisé de la couche de source Al Ga As N+ est diffusé dans une couche d'électrons bi-dimensionnels formée dans une haute concentration i.'0 entre la couche d'écartement Al Ga As et la couche tampon de Ga As N du fait d'un processus de recuit dans la formation d'une région à implantation ionique de sorte que la mobilité des électrons est diminuée, un transistor  Due to the fact that an ionized donor of the Al GaAs N + source layer is diffused in a bi-dimensional electron layer formed in a high concentration i.'0 between the Al GaAs spacer layer and the layer Ga As N buffer due to an annealing process in the formation of an ion-implanted region so that the mobility of the electrons is decreased, a transistor

du type HEMT décrit ci-dessus présente des caractéristi-  of the HEMT type described above has characteristics

v= 5 quesmédiocresde bruit de faible niveau et de a I 4 Dno D aun 4 uew Joj uo D 4 Duor v ina Dnpuo D-was ap:  v = 5 low-level noise and a low noise level in a 4 Dno D 4

+.;sods p uncp uoi e Dl Tqe ap gpeo rd un suep luo Tzuau.  +, sods p u tp uo and Dl Tqe ap gpeo r a Suu luo Tzuau.

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0 Z 9599 Z0 Z 9599 Z

auams Jd el ap -àJ-d uolzest Lep ap 2 pow np uoi 4 disp f Dsp" el i a Dej 5 S 4 ua Jedd E snld 4 uo Jpuai Aap U Oi 4 Ua A Ui T  auams Jd el ap-en-uolzest Lep ap 2 pow np uoi 4 disp f Dsp "el i a Dej 5 S 4 ua Jedd E snld 4 uo Jpuai Aap U Oi 4 Ua A Ui T

a Buamsid el ap sa 5 eque Ae sai 4 ne 4 a snssap z sqnq sa-  a Buamsid el ap sa 5 ece Ae sai 4 n 4 a snssap z sqnq sa-

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s Jna 14 npuo D-iwas sap 7 uos rnb a BDJTD Tnpuo D a Bleixez Tde a D Jnos ap a L Dn OD a J Qiwa Jd aun a la Txe rde 4 uawa 4 the I pagpno D aun Jawo 1 + l 4 ue 1 s Tsuo D Uo T 1 Jedo auin Ios F lwas uo T 4 UDU V Jna Tqnpuom-iwas 4 ei 4 yrs a year ago qq qqsqns no anb Tuap T uo T Duo t ina 4 npuo D-iwas a qsa Tnb ale Txe 4 Tde uodwe anom DD aun dawi Jo i that Cs Tsuo D uoiqegdo aun: pua Adwo Dalianb a) ua asz Sde I n qsa Uo Ti D Uor V san Di JD Tnpuo D-Twas saq 4 Dno D ap s Tua J + pj-T ua Bwallan 4 nw his Jua B sap a De L Ja BF UI V xnezjgew his D ap Tm UI ++ ep a Dua B + Tp aun V llp a O e + Jaqu T p la Tuaqod ap S 4 nd a suep siauuoisuawip-Tq suojdal Ip 0 t Z 999 Z aew Jo sa a D Jnos ap eq Dn OD a 44 a Da Ae Aio 4 JS 4 "o: e 4 uo D a 4 uew Jo + Z al IT 5 ap apo; 4 Dal aun ajip- _-_ sae 3 apuewwmo D ap apo JIB Dal aun 4 to his A 14 Dadsa J 61 _N se 9 4 ua Bwa J An O Da J ap saq Dno D sal ns seaw Joo 4 uos 4 uawai Ano Da J ap saq Mno D sa D My Ae Anbi Twqo qe Duo D a queiw Jo D ús 4 Z ul e ap ap apo 4 malp aun qa azinos ap apoj Dalp aun al Tp-i O -4 sa BD i 4 Ue Jno D ap sapo J 4 al apuomas 4 a ai Tmwa Jd sas sveg Iv quewa B Jen Up aq Bno D el ap o 4 D al Da Ae: e 4 uoz ua ual A 61 _N s Ve 9 4 ua Wa J Ano Da J ap a 4 Dno D el esnld a (Eesaw ain T 4 D Tn J 4 s el ap I uodwe 4 aq Dnoz el ep a Tojp 4 aa 4 Dneti sg-q I sa Jns a Wo JDJ 4 its 61 _N s Ve 9 Ua W Ba J An ODBJ ap a 4 Dno D aun 2 T _N s Ve 9 ap uoddw aq Dno D el ap uoi Dqa Co Jd u B a 4 Jed aunp Ba De Jr S ns e Jns the Txe Td asouess To JD Jed sasw JO + U Os / LT _N salt V a 2 Dnos 7 ap a B Dno D aun: ka gl s Ve Sl U 4 Uw Ba W Jemp to 4 Dnom to B 4 TJDSB Jd uoibei

el a 4 a-o Jd as allanbel suep esaw ainwnn-qs aun ua B Dwjo-  el a 4 a-o Jd as allanbel suep esaw ainwnn-qs aun au B Dwjo-

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0 Z 9599 Z0 Z 9599 Z

W 3 H i: ad A; np Jos Tsue J 4 un;p a Dueinpuo Dsue J; el 4 ue Jol Ilwe ua aessieqe ads qnad I Tnas ap uoisua aun 'isumj -ainpgd ad V ar^ij e a Dinos ap a Bue 4 sis Je el anb a 4 os ap ad 43 ejedsip e;uauua TA s Veg IV quawa Jenp aqmnom el ap;a +N s Vegl V a D Jnos ap a 4 fno D ma 4 a D ap sa Due 4sts 5 O J sal B (Z a Jn 61 i el 'a I T ari ET+ e V ua BDU 9-J) ainazdque anbiu 4 ua; el ap _N Sfe 9 ap uodweq a 4 qnon el qa s Veg 91 V; uawamde 4 je p a Lpno D el 4 +N sveg Iv ad Jn Os ap a Lpno D el azqua uo; zrnpuon ap apueq aun;p 9 znuiquoms Tp aun V sanp aiq Xa-q ep sa Due:sts 9 d xn Bp sal Ba:zrns Jed = Iauuo isuaw P -rq uod 4 alep aqonnon un B a Ae ze Luo D ua uawa Da Jip 4 ua^A 61 4 uawa J^noad J ap aqmno D a,4,a D anb a B 4 os ap sú 2 úIZ U Izedp ap apo J 4 D Ia I; ap qa ainos ap apoj 43 a Ie BTI ap a-nai Jg+ui a Tied el suep agw Jo J sa 6ST +N s Veg ci Uaw J Aino Dap no el anas al ap no D elsuoi el suep quawalnas saq Twil queqq SI s Veg L 9 4 uawa 4 Jemqp aqmno D el;a LI _N s Ve 9 j B az Jnos ap a 4 qno D el Bajlno U 3 úZ; u Tedp ap apojq Da II a TZ a D Jnos ap apo J Dal BI a B Jua uo Tsuaq ap a Duad I++Tp aun e r P úp _Ni N s Ve 9 ap uodweq aq Dnon el ap a De+jns el V ewio+ leuen al sia Aed 4 e S 5 a Jndw T s Bal ed uoisjadsip sues assa BTA ane 4 L V a 3 eldep as Iauuoisuaw Tp-Tq uod a Iel ea 4 Tns de d 21 _N sye 9 ap uodwe; aq Bno D el ap a ST s Veg IJ quawa 4 je D 9 p a Bgno DD a T el ap a Bekja 4 uilI i uoqe Ju 3 auo 3 B arneq aun B ue Luasud ISUUO SU Wapp-Fq uo J Da I 9;p a Bqno D aun s Jole aw Jdo eiu 96 Ia UU Ol SUBW Ip-Tq uodj Da Tf-l '-Ip Ue 5;T Os lauuo Zsuaw 7 p -Tq uo JD Bal un nb uoàe ap s Tuo T qsa LI _N s Ve B Iv a Dldnos ap aq 4 Dnoz el ap Jdiauuop un SZ alij T 5 ap apo J;ala Ip aun 1 l agnb F Ildde qsa uo Tsua B aun zs Ssnssap-Tn aq T zdp ain 4 njs el ap 1 WBH ad Aq np J Ostslet Vs un sueo _LT _N S Ve DIV am Jn Os ap a 4 Dno D el ap a 5 sodxa a B Di L- jns e I ins B   W 3 H i: ad A; Jos Tsue J 4 a; p a Dueinpuo Dsue J; and 4 ue Jol Ilwe ua aessieqe ads qnad I Tnas ap uoisua to the isumj -ainpgd ad V ar ^ ij ea Dinos ap a bue 4 sis I el anb a 4 bones ad ad 43 ejedsip e u u ua ua ve Veg IV quawa Jenp aqmnom el ap; a + N s Vegl V a D Jnos ap a 4 fno D ma 4 a D ap sa Due 4sts 5 OJ sal B (Z a Jn 61 i el a ariad and ee V ua BDU 9-J) ainazdque anbiu 4 ua; el ap _N Sfe 9 ap uodweq a 4 qnon el qa s Veg 91 V; uawamde 4 I p a Lpno D el 4 + N sveg Iv ad Jn Os ap Lpno D el azqua uo; r 9 9 9 9 9 9 Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due Due-------------- Jip 4 ua ^ A 61 4 uawa J ^ noad J ap aqmno D a, 4, a D ab a B 4 os ap sú 2 úIZ U Izedp ap apo J 4 D Ia I; ap qa ainos ap apoj 43 a BTI ap a-nai Jg + ui a Tied el suep agw Jo J his 6ST + N s Veg ci Uaw J Aino Dap no el anas al ap no D elsuoi el suep quawalnas saq Twil queqq SI s Veg L 9 4 uawa 4 Jemqp aqmno D el; a LI _N s Ve 9 j B az Jnos ap a 4 qno D el Bajlno U 3 úZ; u Ted ap apojq Da II a TZ a D Jnos ap apo J Dal BI a B Jua uo Tsuaq ap a Duad I ++ Tp aun er P úp _Ni N s Ve 9 ap uodweq aq Dnon el ap a De + jns el V ewio + alen A ss 4 th S 5 a Jndw T s Bal ed uoisjadsip sues assa BTA ane 4 LV to 3 eldep as Iauuoisuaw Tp-Tq uod a lel ee 4 Tns de d 21 _N sye 9 ap uodwe; aq Bno D el ap a ST s Veg IJ quawa 4 I D 9 pa Bgno DD a T el ap a Bekja 4 uilI i uoqe Ju 3 auo 3 B arneq au B ue Luasud ISUUO SU Wapp-Fq uo J Da I 9; pa Bqno D aun s Jole aw Jdo eiu 96 Ia UU OIL I-Tp-Tq-tp-Tp-Ip Ue 5; T Os lauuo Zsuaw 7 p -Tq uo JD Bal a nb uoàe ap Tuo T qsa LI _N s Ve B a a ddnos ap aq 4 Dnoz el ap Jdiauuop a SZ alij T 5 ap apo J; ala Ip aun 1 l agnb F Ildde qsa uo Tsua B aun zs Ssnssap-Tn aq Tpdp ain 4 njs el ap 1 WBH ad Aq np J Ostslet Vs a sueo _LT _N S Ve DIV am Jn Os ap a 4 Dno D el ap a 5 sodxa a B Di L- jns e I ins B

0 Z 9599 Z0 Z 9599 Z

+N s Ve 9 ap Bq Dno D el a P a De_ ns el ins 4 uawalloip ap a pmo Jd el J 2 d LT +N s Ve YSI a Djnos ap aq Lno D el ap B nari Btdns a Tpjed e I 3 p uo T 4 da D Xal V aue Wsa J a T 4 Jed el ins sapw Jo+ a B;Tnsua,uos 'új TZ UT Jep ap apo D Bai U aun a a Djnos ap apojmagl aunl -Buaww Bap J Ad apuuo Tzuaw O^ 30 W no SW apoq 4 wm el Jed oz LI +N sfeg 9 I ap a Bqnom ap aj Dnos el ap 4 a ú agsodxa _N s Veg ap uodwe 4 aqmno D el Jns agwjo O; sa agsi Xiueld ajq hnad ae Jjns el 4 uop tu ú uo JT Aua B p Jnassied 5 aun,ue/Ae +N s Veg ap a Bmnom aun B Sgt a Uin'Li el ap ade B;B I V uawal T De iawioj as es q quawe sai nnad u Te p-aminos 4 uejno D ap s:nooz Xd un îST sfeg 19 4 uewa Bje D;p aq Dno D el ap a Jnal B Su T ai 4 led el suep uozqa Co Jd ua L 1 uodwe L a B Un OD el q Ue WJO+ U 3 -a 4 TJ 3 sa Jd Jnapuo D+o-jd el V _N s Ve J ap a 4 nnon el ap a Jn^ejb 5 jed awjo+ sa úT _N s Ve 9 ap uodwe 4 aqno D oz aun 4 snld ap esa aplwnq a Jn Ae BJ ap no a Unps a Jn Ate WJ ap apoq 4 gw aun Jed as T Ile a 4 Tnsua 4 sa a Jn Ae SB aunl a J Ieu Tp Jo a Tqde LJ 5 oqfl TO 4 od el jed s Veg IV ap ay 4 no D el 4 a +N s V We 9 V 1 ap a Bmno Z el a Jp-o I su Wp 4 Wue Aej 5 ua agwio Wj 4 uos T s Vi/91 J 4 uawaqjpmgp ay Dnon q aun a LI +N sveglv a D Inos ap aq Mno Z aun ea 4 TI Dsa Jd U O o Ib 5 el suep esaw ewmq Ds un Jawjoj ap UT -Ie a 4 T ns U 3 94 a Jndw T awwo D es TI Tx N siole qsa TS al OAJ 3 WJ no 3 GW apo 4 gw el ed IT Uel Wosl T was syeg ap 4 e Jsqns el ins a Bipiol S auep S Bw JLO r+ 4 UOS V 00 & 1 002 ap inassiede Sun 4 / W/8 T O T X ú BTOI x IT ap se 4 a Jndw T ua uoi 4 ej 4 ua Buo D aun 4 ueÀe N sveg Iv ap ae Dnom aun 4 a ' Ot 1 00 Qs ap Jnassi Ted U aun queÀe s Ve 9 IV ap aq Dno D sun e W 4 Z e g O ap Jnassi Ted aun qa l W/It OT X I V a Jnamjgjuz ssqaindwi ua uo Be Uua Duo aun U uequas Ud _N s Veg ap aqmno D sun sz ain 5 rl el sp eade;,I suea -snssap q U Uo I 4 Ua W 2 a-n Fbti el ap uoe T 4 L Diqe 4 2 p pgo D O Jd  + N s Ve 9 ap Bq Dno D el a P a De ns el ins 4 uawalloip ap a pmo Jd el J 2 d LT + N s Ve YSI a Djnos ap aq Lno D el ap B nari Btdns a Tpjed e I 3 p uo T 4 da D Xal V aue Wsa J a T 4 Jed el ins sapw Jo + a B; Tnsua, uos' új TZ UT Jep ap apo D Bai U aun aa Djnos ap apojmagl aunl -Buaww Bap J Ad apuuo Tzuaw O ^ 30 W no SW apoq 4 wm el Jed oz LI + N sfeg 9 I ap a Bqnom ap aj Dnos el ap 4 a ú agsodxa _N s Veg ap uodwe 4 aqmno D el Jns agwjo O; its AGSI Xiueld ajq hnad ae Jjns el 4 uop you ú uo JT Aua B p Jnassied 5 aun, eu / Ae + N ap s Veg has Bmnom aun Sgt B has Uin'Li el ap ade B; BIV uawal T De iawioj you're q quaqe sai nnad u Te p-aminos 4 uejno D ap s: nooz Xd an ISST sfeg 19 4 uewa Bje D; p aq Dno D el ap a Jnal B Su T ai 4 led el suep uozqa Co Jd ua L uodwe L a B a OD el q Ue WJO + U 3 -a 4 TJ 3 his Jd Jnapuo D + o-jd el V _N s Ve J ap a 4 nnon el a nd a jn ^ ejb 5 jed awjo + his úT _N s Ve 9 ap uodwe 4 aqno D oz aun 4 snld ap esa aplwnq a Jn Ae BJ ap no a Unp a Jn Ate WJ ap apoq 4 gw aun Jed as T Ile a 4 Tnsua 4 sa to Jn Ae SB aunl a J aeu Tp Jo a Tqde LJ 5 oqfl TO 4 od el jed s Veg IV ap ay 4 no D el 4 a + N s V We 9 V 1 ap a Bmno Z el a Jp-o I su Wp 4 Wue Aej 5 ua agwio Wj 4 uos T s Vi / 91 J 4 uawaqjpmgp ay DNo q Aun LI + D has N sveglv Inos ap aq Mno Z aun Others 4 TI Dsa Jd OU o el 5 Ib suep ESAW ewmq Ds an ap Jawjoj UT -ië 4 ns T U 3 94 a Jndw T awwo D es TI Tx N siole qsa TS al OAJ 3 WJ no 3 GW apo 4 gw ed IT Uel Wosl T was sy eg ap 4 e Jsqns el ins a Bipiol S aup S Bw JLO r + 4 UOS V 00 & 1 002 ap acted on Sun 4 / W / 8 TOTX ú BTOI x IT ap se 4 a Jndw T ua uoi 4 ej 4 ua Buo D aun 4 UeA N sveg Iv ap ae Dnom au 4 a 'Ot 1 00 Qs ap Jnassi Ted U aun ase s Ve 9 IV ap aq Dno D sun O W 4 Z eg O ap Jnassi Ted aun w w w w it XIV a Jnamjgjuz ssqaindwi ua uo Be Uua Duo aun U uequas Ud _N s Veg ap aqmno D sun sz ain 5 rl el sp eade;, I suea -snssap q U Uo I 4 Ua W 2 yy F u lth u p t 4 L Diqe 4 2 p pgo DO Jd

un 4 ue W Jsnl I' adno D ua san A sap 4 uos 3 1 Vt ' rk sa-  a 4 W ow to the Adno D ua san A sap 4 uos 3 1 Vt 'rk

0 Z 9599 Z0 Z 9599 Z

1 ic L'électrode de source et l'électrode de drain 21, 23 sont formées dans un métal ohmique, par exemple,  1 ic The source electrode and the drain electrode 21, 23 are formed of an ohmic metal, for example

Au Ge/Ni/Au.At Ge / Ni / Au.

La fenftre 24 est formée en continu en éliminant la couche de Ga As N+ sur la surface supérieure de la couche de source Al Ga As N+ 17 par photolithographie Des couches de recouvrement Ga As N+ 19 sont ensuite formées par les couches de Ga As N+ sur la partie supérieure de la couche  The window 24 is formed continuously by eliminating the GaAs N + layer on the upper surface of the Al GaAs N + 17 source layer by photolithography GaAs N + 19 overlay layers are then formed by GaAs N + layers on the upper part of the layer

tampon de Ga As N 13.buffer of GaAs N 13.

Une électrode de grille 25 est alors formée sur la couche de source Al Ga As N+ exposée 17 de façon qu'une structure identique à une structure de la figure 4 C soit réalisée. L'électrode de grille 25 est ensuite formée en métal  A gate electrode 25 is then formed on the exposed Al GaAs N + source layer 17 so that a structure identical to a structure of FIG. 4C is realized. The gate electrode 25 is then formed of metal

Schottky, par exemple, Ti/Pt/Au.Schottky, for example, Ti / Pt / Au.

Comme décrit ci-dessus, du fait que la couche de source Al Ga As N+ et la couche d'écartement Al Ga As sont formées dans la seul'e région de grille et que la couche de recouvrement Ga As N+ est formée sur la couche tampon de Ga As N dans la région de source et dans la région de drain de sorte qu'une résistance de source peut Etre réduite en amenant directement ces couches de  As described above, since the source layer Al Ga As N + and the spacer layer Al Ga As are formed in the only gate region and the GaAs N + cover layer is formed on the layer GaAs N buffer in the source region and in the drain region so that a source resistance can be reduced by directly bringing these layers of

recouvrement en contact avec une couche d'électron bi-  covering in contact with a bi-layer of electron

dimensionnel formée à la surface de la couche tampon, les caractéristiques de bruit de faible niveau et de haute fréquence d'un transistor du type HEMT peuvent tre améliorées. I -N ad/4 np qsa uo T 4 npuoz ap _ ad Aq ja Twe Jd q Tpa I anb am ua szBoe De ' uotetipu B Aai e 1 T q o S uoi 4 DUO( i Jn Dnpuo D-TW Bs ap + 41 Tsods O 'ú s Il 9 T-uo 1 uo C V Jn;a 1 npuo-Tlwas Un qsa (T) 4 uawa 1 eqzp a 4 Dno D eap Pe I anb an ua 4 a svfe 9-uo T 4 uor F Jni 4 nnp UOD-Twas un 02 -sa;e 4 sqns r Tpal anb a D ua sii 4 eie D 4 T uo Iqe Dlpua AJ el U O olas uo 1 Duoc v Jna Dnpuo D-Twas ap I Tsods Ta -Z (LI) Dm Jn OS ap a 4 mnon el Ins am Dnos ap aq Dnom el Da Ae A)44 o L Ds 4 De 4 uoo un 4 uew JO apuewwo D ap apo Ji Dal I aunf 4 a S ST -uawa-4-emip, aumno D el Jns (*I) Iuawa-Je Dp a Dno D el V anb-4 uapl uol Duor v una Do+ u npuo-Wun Jed aw Jouo npuo ap ad Ja Tiwai Bd un;p (LT) e D Jnos ap Baqno D aun i ( 61) 4 Ua Wa JA^no Da ap saq Dno D aw Q Txnap O z e I 4 a a J Twaj Id el a J 4 ua ( 21) uodwe 4 aqno D e I ns uodwe 4 aqmno D agpe I ap quam;Tp uoim Duof V i Jna Dnpuo D -Twas un ed agwio (g T) 4 uawa B 4 Jez Dp a Bmno D aun l ( 6 T) uaw J^Anom D De J ap sa 4 Dno D apu O Des 4 a a JQ Twaed sal q UBWBAATD 3 dsai Da Ae anbiwqo 4 De 4 uo un g T uewjo I;ueen DD ap sa POJ 4 DB Il apuo Das 4 a Ba I Twaid sap (úI) uodweq Bq no D a P 4 pel ns Tu Tip a Ie A^aku T un jed a J 4 ne;I ap aun I sajedes 4 uos Fnb ( 2 T) uodwe 4 a Lqnom a 4 Tpe I a nb 14 uap T uo Dguo C e ina Bm Dnpuom -Twas un Jed saewioj uot;npuo D ap ad A 4 ja Twa Jd unp 01 ( 61) 4 uawa J Anoma J ap sa Dqmno D apuoms qa a BQ Twa Jd sap ;kejsqns 4 Tpa I ins 4 e;sqns -4 pne anb T 4 uapl uoruor V ina 4 Dnpuoz-iwas un jed agwioj uo;qnpuo D ap ad AÀ -azwaid unp (s El) uodwel aq Dno D aun (TT) 4 ueelos 5 T-Iwa S uoimuor V Jnaqnpuo D-Iwas;e isqns un puaidwo D 1 inb a B ua estiqeie D luoi Tuor l inaqnpuo D-Iwas ap T 4 Isods-TU 'T  formed on the surface of the buffer layer, the low-level and high-frequency noise characteristics of a HEMT type transistor can be improved. I -N ad / 4 np qsa uo T 4 npuoz ap _ ad Aq ja Twe Jd q Tpa I anb am ua szBoe De uotetipu B Aai e 1 T qo S uoi 4 DUO (i Jn Dnpuo D-TW Bs ap + 41 Tsods O 'ú s Il 9 T-uo 1 uo CV Jn; a 1 npuo-Tlwas A qsa (T) 4 uawa 1 eqzp a 4 Dno D eap P anb an ua 4 a svfe 9-uo T 4 uor F Jni 4 nnp UOD-Twas a 02 -sa; e 4 sqns r Tpal anb a D ua sii 4 eie D 4 T uo Iqe Dlpua AJ el UO olas uo 1 Duoc v Jna Dnpuo D-Twas ap I Tsods Ta -Z (LI) Dm Jn OS ap a 4 Miss El Ins am Dnos ap aq Dnom el Da Ae A) 44 o L ds 4 of 4 uoo a 4 uew JO apuewwo D ap apo Ji Dal I aunf 4 a S ST -uawa-4-emip, Jnos (1) Iuawa-Je Dp a Dno D el V anb-4 uapl uol Duor v una Do + u npuo-Wun Jed aw Jouo npuo ad ad Ja Tiwai Bd a; p (LT) e D Jnos ap Baqno D aun i (61) 4 Ua Wa JA ^ no Da apaq Dno D aw Q Txnap O ze I 4 aa J Twaj Id el a J 4 ua (21) uodwe 4 aqno D e I ns uodwe 4 aqmno D agpe I ap quam; Tp uoim Duof V i Jna Dnpuo D -Twas a ed agwio (g T) 4 uawa B 4 Jez Dp a Bmno D aun l (6 T) uaw J ^ Anom D From J ap sa 4 Dno D apu O 4 aa JQ Twaed sal q UBWBAATD 3 DSAI Da Ae anbiwqo 4 of 4 uo a g T uewjo I; ueen DD ap its POJ 4 DB It APUO Das 4a Ba I Twaid sap (UI) uodweq Bq No. D P 4 pel Do you know what you think about it? Do you know what you think about it? Do you have a lesson? Do you have a lesson? Do you know how to do it? a Jed saewioj uot; npuo D ap ad A 4 ja Twa Jd unp 01 (61) 4 uawa J Anoma J ap sa Dqmno D apnoms qa a BQ Twa Jd sap; kejsqns 4 Tpa I ins 4 e; sqns -4 pne anb T 4 uapl uoruor V ina 4 Dnpuoz-iwas a jed agwioj uo; qnpuo D ap ad A-azwaid unp (s El) uodwel aq Dno Dnn (TT) 4 ueelos 5 T-Iwa S uoimuor V Jnaqnpuo D-Iwas; e isqns a puaidwo D 1 inb a B ua estiqeie D luoi Tuor l inaqnpuo D-Iwas ap T 4 Isods-TU 'T

: SNOI V 3 IGNB 3 A 3: SNOI V 3 IGNB 3 A 3

ITIT

0 Z 9599 Z0 Z 9599 Z

I 2 4 Dispositif de semi-conducteur à jonction selon la revendication 1, caractérisé en ce que ladite couche d'écartement ( 15) et ladite couche de source ( 17) sont formées sur ladite couche tampon ( 13 > en une structure mesa. Dispositif de semi-conducteur à jonction selon la revendication 4, caractérisé en ce que lesdites première et seconde couches de recouvrement ( 19) sont formées par  A junction semiconductor device according to claim 1, characterized in that said spacer layer (15) and said source layer (17) are formed on said buffer layer (13) into a mesa structure. semiconductor device according to claim 4, characterized in that said first and second cover layers (19) are formed by

couverture d'un c 8 té incliné d'une structure mesa.  cover of an inclined tee of a mesa structure.

Oc) 6 Procédé de fabrication d'un dispositif de semi-  Oc) 6 Method of manufacturing a semiconductor device

conducteur à jonction qui forme une couche d'électron bi-  junction conductor which forms a bi-layer of electron

dimensionnel dans un puits de potentiel d'interface d; à une différence d'affinité desdits matériaux à l'interface  dimensional in an interface potential well d; at a difference in affinity of said materials at the interface

de genre mutuellement différent des couches semi-  mutually different kind of semi-

conductrices à jonction caractérisé en ce qu'il comprend: une étape consistant à former une couche tampon épitaxiale qui est un semiconducteur à jonction identique audit substrat sur le substrat semiconducteur t-0 à jonction semi-isolant t une étape consistant à former une couche d'écartement épitaxiale et une couche de source épitaxiale  junction conductive conductors characterized in that it comprises: a step of forming an epitaxial buffer layer which is a semiconductor junction identical with said substrate on the semi-insulating junction semiconductor substrate t-0; epitaxial spacing and an epitaxial source layer

d'un premier type de conduction qui sont des semi-  of a first type of conduction which are semi-

conducteurs à jonction différents de ladite couche tampon Dû' sur la couche tampon une étape consistant à graver ladite couche d'écartement ladite couche de source et une partie de ladite couche tampon afin de former une structure mesa; une étape consistant à former une couche de recouvrement épitaxiale d'un premier type de conduction qui est un semiconducteur à jonction identique à cette couche tampon sur ladite structure mesa et sur ladite couche tampon une étape consistant à former des première et seconde / -ap Twn 4 a Jn^Ae J ap uo Te-pdo aun Jed na ages a Jn Aei Jb jed apn 4 D-a+a 4 sa vsaw a Jn 4 n J 4 s a Tlpl ap uof:ew Jo+ el Jinod a Jn Aei 6 ap uo T;ejedo aun nb a B ua 9 s TJ Fe DJ sq uo 01 e Dlpua Aa J -E uo Tlas uo Tuo Dr oz I? na 4 np Uo D-1 w Bs unp Uo O Te Dl Jqe+ a P p 92 P 9 Jd -6 _N a Bc A; BT 4 sa uotpnpuo D ap ad M Jawa-wd;T Pp I anb am ua p St e / uoie D Dipu A el uoles u Oi Z Duor V Jnaqmnpuom-was un;p uoi Teit Jqe+ ap pp D J-d '8 -sev 1 V u O Tz; uor i ina B Dnpuo D ST was un qsa quawa-eivp aqpno D a B 4 pe I anb a ua wa s&Jeg uo T;Duor q inak Dnpuo D-Twas un 4 sa 4 e Jdsqns,-4 pal anb am ua ?s Tde Jei '9 uolqe D Tpua Aa J el uolas uo T:Duor e Jna:npuo D-Tw Bas unp uo T;e D-Jxqe+ ap ppp DO Jd /L -a JÀ 4 e ua:F al Tpej suep aesodxa amdnos ap aq-Dno D a pe I ins U Ba J Awdno Da B ap I 4 Dno D a Tpevl ap a B Ol S qsa Tnb apuewwo D ap apo J 4 Daje aun dawi O + e que 4 sisuoz ade 4 p aun qa eesaw a-nlpn Jàs aqpp el ap a Jnal T Jdns a Tq Jed el Jasod Xa Jnod am J 4 gua B aun Jawi JO ap u T-le uawa J Ano Da J r ap sa 4 Dno D sa B Tpsal -a^e j 5 eq ue-sisuo D ade 4 aun 4 uawa Ailnaadsai es Baw a Jnn 14 Dns f a 4 pe ap 4 o Jp xa am 4 ne D s F 94 D sap 4 uwa 1 e^noma D Bp saq Dno D sa B Tpsa I Jns sapo J Dal I r 2 T 0 t Z 9 G 9 Z  junction conductors different from said buffer layer D 'on the buffer layer; a step of etching said spacer layer with said source layer and a portion of said buffer layer to form a mesa structure; a step of forming an epitaxial covering layer of a first conduction type which is a junction semiconductor identical to this buffer layer on said mesa structure and on said buffer layer a step of forming first and second / -p Twn 4 to Jn ^ Ae J ap uo Te-pdo to Jed na ages to Jn Aei Jbjed apn 4 D-a + a 4 his vsaw to Jn 4 n J 4 his Tlpl ap uof: ew Jo + el Jinod to Jn Aei 6 ap uo T; ejedo aun nb a B ua 9 s TJ Fe DJ uo 01 01 Dlpua Aa J -E uo Tuo uo Tuo Dr oz I? ## EQU1 ## ## EQU1 ## where: ## EQU1 ## BT 4 its uotpnpuo D ap ad M Jawa-wd; T Pp I anb am ua p st e / duo D Dipu A el uoles u Oi Z Duor V Jnaqmnpuom-was a p uo Teit Jqe + ap pp D Jd '8 -sev 1 V u O Tz; or i D D D D D ST ST ST ST ST ST ST ST ST ST ST ST ST ST ST ST ST;;;;;;;;; 4 4 4 4 4 4 4 4 4 4 4 4 4 Tde Jei '9 uolqe D Tpua Aa J el uolas uo T: Duor e Jna: npuo D-Tw Bas unp uo T; e D-Jxqe + ap ppp DO Jd / L -a Ja 4 e ua: F al Tpej suep aesodxa amdnos ap aq-Dno D a pe I ins U Ba J Awdno Da B ap I 4 Dno D a Tpevl ap a B Ol S qsa Tnb apuewwo D ap apo J 4 Daje a dawi O + e that 4 sisuoz ade 4 p aun qa eesaw a-nlpn Jàs aqpp el ap a Jnal T Jdns Jd el Jasod Xa Jnod am J 4 gua B aun Jawi JO ap u T uwa J Ano Da J r ap a 4 Dno D sa B Tpsal-ae 5 eq ue-sisuo D ay 4 aun 4 uawa Ailnaadsai es Baw a Jnn 14 Dns fa 4 pe nd 4 O p xa am 4 ne D s F 94 D sap 4 uwa 1 e ^ noma D Bp saq Dno D sa B Tssa I Jns sapo J Dal I r 2 T 0 t Z 9 G 9 Z

FR9003009A 1989-12-31 1990-03-09 SEMICONDUCTOR WITH JUNCTION COMPRISING A HETEROJUNCTION STRUCTURE. Pending FR2656740A1 (en)

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KR1019890020733A KR910013568A (en) 1989-12-31 1989-12-31 Compound Semiconductor Device and Manufacturing Method Thereof

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JPH0444328A (en) * 1990-06-11 1992-02-14 Mitsubishi Electric Corp Semiconductor device and manufacture thereof
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JP6690320B2 (en) * 2016-03-11 2020-04-28 住友電気工業株式会社 High electron mobility transistor and method of manufacturing high electron mobility transistor
US11515410B2 (en) * 2020-10-30 2022-11-29 Raytheon Company Group III-V semiconductor structures having crystalline regrowth layers and methods for forming such structures

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GB2239557A (en) 1991-07-03

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