Mhedzisiro yeSiC substrate uye epitaxial zvinhu pane MOSFET mudziyo maitiro

Triangular defect

Triangular defects ndiyo inouraya zvakanyanya morphological defects muSiC epitaxial layers. Nhamba yakawanda yezvinyorwa zvinyorwa zvakaratidza kuti kuumbwa kwematatu akaremara kwakabatana ne3C crystal fomu. Zvisinei, nekuda kwemaitiro ekukura akasiyana, morphology yezvizhinji zvetriangular defects pamusoro pe epitaxial layer yakasiyana zvakasiyana. Inogona kukamurwa zvakaenzana mumhando dzinotevera:

(1) Pane kukanganiswa kwematriangular ane zvimedu zvakakura kumusoro

Rudzi urwu rwehutatu hurema hune hombe spherical particle kumusoro, iyo inogona kukonzerwa nekudonha kwezvinhu panguva yekukura. Nzvimbo diki ine mativi matatu ine nzvimbo yakakasharara inokwanisa kucherechedzwa zvichidzika kubva mumusoro. Izvi zvinokonzerwa nekuti panguva ye epitaxial process, maviri akasiyana-siyana e3C-SiC akaumbwa akatevedzana munzvimbo yetriangular, iyo iyo yekutanga tambo ine nucleated pane iyo interface uye inokura kuburikidza ne4H-SiC nhanho inoyerera. Sezvo kukora kwe epitaxial layer kunowedzera, chikamu chechipiri che 3C polytype nucleates uye inokura mumakomba maduku ane triangular, asi danho rekukura re 4H harina kuvhara zvachose 3C polytype nzvimbo, zvichiita kuti V-shaped groove nzvimbo ye 3C-SiC ichiri zvakajeka. zvinooneka

(2) Pane twudiki twudiki kumusoro uye hurema hwekatatu hwakakasharara

Zvimedu zviri pa vertices yerudzi urwu rwekuremara kwetriangular zvidiki zvakanyanya, sezvakaratidzwa mumufananidzo 4.2. Uye yakawanda yenzvimbo yetriangular yakafukidzwa nenhanho inoyerera ye4H-SiC, ndiko kuti, iyo yose 3C-SiC layer yakanyatsobatanidzwa pasi pe4H-SiC layer. Chete nhanho dzekukura dze4H-SiC dzinogona kuoneka pane triangular chirema chepamusoro, asi matanho aya akakura kupfuura akajairwa 4H crystal kukura matanho.

(3) Zvikanganiso zvetriangular zvine nzvimbo yakatsetseka

Rudzi urwu rwehutatu hurema hune morphology yakatsetseka, sezvakaratidzwa mumufananidzo 4.3. Nokuda kwehurema hwakadaro katatu, 3C-SiC layer yakafukidzwa nenhanho inoyerera ye 4H-SiC, uye 4H crystal fomu pamusoro pepamusoro inokura zvakanaka uye yakatsetseka.

Epitaxial gomba defects

Epitaxial pits (Makomba) ndeimwe yeanowanzo zivikanwa pamusoro morphology kuremara, uye iwo akajairwa pamusoro morphology uye chimiro chechimiro chinoratidzwa muMufananidzo 4.4. Nzvimbo ye threading dislocation (TD) corrosion pits yakacherechedzwa mushure meKOH etching kuseri kwechigadziro ine tsamba yakajeka nenzvimbo ye epitaxial pits isati yagadzirirwa mudziyo, zvichiratidza kuti kuumbwa kwe epitaxial gomba defects kune chokuita ne threading dislocations.

karoti kukanganisa

Karoti kuremara kwakajairwa pamusoro pekuremara mu4H-SiC epitaxial layers, uye yavo yakajairika morphology inoratidzwa muMufananidzo 4.5. Iyo karoti defect inonzi inoumbwa nekusangana kweFranconia uye prismatic stacking zvikanganiso zviri pane basal ndege yakabatana nenhanho-senge dislocations. Izvo zvakare zvakashumwa kuti kuumbwa kwekaroti kukanganisa kwakabatana neTSD mune substrate. Tsuchida H. et al. akawana kuti kuwanda kwehurema hwekaroti mu epitaxial layer inoenzana nekuwanda kweTSD mune substrate. Uye nekuenzanisa iyo yepamusoro morphology mifananidzo isati yasvika uye mushure mekukura epitaxial, zvese zvakacherechedzwa karoti hurema hunogona kuwanikwa hunoenderana neTSD mune substrate. Wu H. et al. akashandisa Raman kuparadzira bvunzo maitiro kuti aone kuti karoti yakaremara yakanga isina iyo 3C crystal fomu, asi chete 4H-SiC polytype.

Mhedzisiro yehutatu hurema pane MOSFET mudziyo maitiro

Mufananidzo 4.7 ihistogram yekugoverwa kwenhamba yezvimiro zvishanu zvemudziyo une hurema hwematatu. Mutsetse webhuruu une doti ndiwo mutsara unopatsanura wekuderedzwa kwechishandiso, uye mutsara une doti dzvuku ndiwo mutsara wekupatsanura wekutadza kwemudziyo. Pakutadza kwechishandiso, kukanganisika kwematriangular kune kukanganisa kukuru, uye mwero wekutadza unodarika 93%. Izvi zvinonyanya kukonzerwa nekukanganiswa kwematriangular kukanganisa pane reverse leakage maitiro emidziyo. Kusvika 93% yemidziyo ine triangular kuremara yakawedzera zvakanyanya reverse leakage. Pamusoro pezvo, kukanganiswa kwematriangular kunewo kukanganisa kwakakomba pamagedhi ekudonha maitiro, ane degradation rate ye60%. Sezvinoratidzwa muTebhurari 4.2, pakudzikira kwemagetsi echikumbaridzo uye kushatiswa kwemuviri diode hunhu, kukanganisa kwetrianngular kukanganisa kudiki, uye kuwanda kweiyo 26% uye 33% zvichiteerana. Mukutaura kwekukonzera kuwedzera kwe-kupikisa, kukanganisa kwehutatu hurema husina simba, uye chiyero chekuora chinenge 33%.

Mhedzisiro ye epitaxial gomba kukanganisa pane MOSFET mudziyo hunhu

Mufananidzo 4.8 ihistogram yekugoverwa kwenhamba yezvimiro zvishanu zvemudziyo une epitaxial pit defects. Mutsetse webhuruu une doti ndiwo mutsara unopatsanura wekuderedzwa kwechishandiso, uye mutsara une doti dzvuku ndiwo mutsara wekupatsanura wekutadza kwemudziyo. Zvinogona kuonekwa kubva pane izvi kuti nhamba yemidziyo ine epitaxial gomba defects muSiC MOSFET sampuli yakaenzana nenhamba yemidziyo ine triangular defects. Iko kukanganisa kwe epitaxial pit defects pamaitiro emudziyo kwakasiyana neiyo ye triangular defects. Panyaya yekutadza kwemudziyo, chiyero chekutadza kwemidziyo ine epitaxial gomba defects inongova 47%. Kuenzaniswa nekuremara kwematriangular, kukanganisa kwe epitaxial gomba pane reverse leakage maitiro uye gedhi leakage maitiro emudziyo akanyanya kupera simba, nekudzikira reshiyo ye53% uye 38% zvichiteerana, sezvakaratidzwa muTable 4.3. Kune rimwe divi, kukanganisa kwe epitaxial pit defects pachikumbaridzo voltage maitiro, body diode conduction maitiro uye on-resistance yakakura kupfuura iyo ye triangular defects, uye degradation reshiyo inosvika 38%.

Kazhinji, zvikanganiso zviviri zve morphological, zvinoti katatu uye epitaxial gomba, zvine chekuita nekutadza uye kuderedzwa kwehunhu hweSiC MOSFET zvishandiso. Kuvapo kwekuremara kwematriangular ndiko kunonyanya kuuraya, nekutadza kwechiyero chakakwira se93%, kunonyanya kuratidzwa sekuwedzera kwakakosha mukureverse kuvuza kwemudziyo. Midziyo ine epitaxial gomba defects yaive yakaderera yekutadza mwero we47%. Nekudaro, epitaxial pit defects ine simba rakakura pane chikumbaridzo voltage, body diode conduction maitiro uye on-resistance pane hurema hwetatu.