2010B1847                        BL46XU◳ X ⥺ග㟁Ꮚศග࡟ࡼࡿ❅໬࣒࢞ࣜ࢘⣔㟁Ꮚࢹࣂ࢖ࢫࡢ⾲㠃≧ែゎᯒ 㻔II㻕
Analysis on Surface Condition for GaN-based Electron Device
by HAXPES 㻔II㻕⯓㔝 Ὀ⠊ a, 㥖㇂ ົ b, Ⲩ㇂ Ẏ a, Ἑෆ ๛ᚿ a, ಴▱ ಇ௓ b, ᩪ⸨ ྜྷᗈ a
Yasunori Tatenoa, Tsutomu Komatanib, Takeshi Arayaa, Tsuyoshi Kouchia,
Shunsuke Kurachib, and Yoshihiro Saitoaaaఫ཭㟁Ẽᕤᴗ㻔ᰴ㻕 , b ఫ཭㟁ᕤࢹࣂ࢖ࢫ࣭࢖ࣀ࣮࣋ࢩࣙࣥ㻔ᰴ㻕
Sumitomo Electric Industries, Ltd., bSumitomo Electric Device Innovations, Inc.

㟁Ꮚࢹࣂ࢖ࢫ⏝ࡢ n ᆺ❅໬࣒࢞ࣜ࢘㻔n-GaN㻕࡜❅໬ࢩࣜࢥࣥ㻔SiNx㻕ಖㆤ⭷ࡢ⏺㠃≧ែ࡟㛵ࡋࠊ◳ X⥺ග㟁Ꮚศග㻔HAXPES㻕࡟ࡼࡿศᯒࢆ⾜ࡗࡓࠋヨᩱ࡟ࡣࠊO2 ࣉࣛࢬ࣐ฎ⌮ࡋࡓ n-GaN ⾲㠃࡟ SiN⭷ࢆሁ✚ࡋࡓࡶࡢࠊཬࡧࠊ᭦࡟㧗 ࢔ࢽ࣮ࣝࢆ᪋ࡋࡓࡶࡢࠊࡢ 2 ✀㢮ࢆ⏝ពࡋࡓࠋࡲࡓࠊࢳ࣮ࣕࢪ࢔ࢵࣉᢚไࡢࡓࡵࠊヨᩱ⾲㠃࡟ⷧ࠸ AuPd ࢆ⵨╔ࡋ࡚࠸ࡿࠋࢹ࣮ࢱゎᯒ࡛ࡣࠊAuPd ࡢ Au4f ࢫ࣌ࢡࢺࣝࢆ⏝࠸࡚ࢳ࣮ࣕࢪ࢔ࢵࣉ⿵ṇࢆ⾜ࡗࡓୖ࡛ࠊヨᩱ㛫࡛ Ga2p ࢫ࣌ࢡࢺࣝࡢẚ㍑ࢆ⾜ࡗࡓࠋࡑࡢ⤖ᯝࠊ࢔ࢽ࣮ࣝ࡟ࡼࡾ SiNx/GaN ⏺㠃࡟ࡣ㔠ᒓ≧ Ga ࡀ⏕ᡂࡋ࡚࠸ࡿྍ⬟ᛶࡀ♧၀ࡉࢀࡓࠋ࣮࣮࢟࣡ࢻ㸸 GaNࠊSiNxࠊ㧗࢔ࢽ࣮ࣝࠊ◳ X ⥺ග㟁Ꮚศග⫼ᬒ࡜◊✲┠ⓗ㸸
GaN ⣔ࡢ㧗㟁Ꮚ⛣ືᗘ㟁⏺ຠᯝࢺࣛࣥࢪࢫࢱ㻔HEMT㻕ࡣࠊ㧗ฟຊቑᖜ⣲Ꮚ࡜ࡋ࡚ᦠᖏ㟁ヰᇶᆅ
ᒁࡸ⾨ᫍ㏻ಙ⏝㏵࡞࡝࡬ࡢᛂ⏝ࡀᣑ኱ࡋ࡚࠸ࡿࡀࠊᮦᩱᅛ᭷ࡢ⌧㇟ࡢ⌮ゎࡀࡲࡔ୙༑ศ࡛࠶ࡿࠋ≉࡟ࠊ༙ᑟయ࡜⤯⦕ಖㆤ⭷ࡢ⏺㠃≧ែࡣࠊࢹࣂ࢖ࢫ≉ᛶ࡟኱ࡁ࡞ᙳ㡪ࢆ୚࠼ࡿせ⣲࡛࠶ࡿࠋලయⓗ࡟ࡣࠊ⏺㠃࡟Ꮡᅾࡍࡿࢺࣛࢵࣉ࡟㟁Ꮚࡀᤕ⋓ࡉࢀࠊᐤ⏕ⓗ࡞✵ஈᒙࡀᣑ኱ࡍࡿࡇ࡜࡛ࠊHEMTࡢ㟁ὶࢳࣕࢿࣝ⊃✽࡜ฟຊపୗࢆࡶࡓࡽࡍࡇ࡜ࡀ▱ࡽࢀ࡚࠸ࡿ[1] [2]ࠋࡇࡢࡓࡵࠊ⏺㠃ࢺࣛࢵࣉࡢపῶࡣࠊᕤᴗⓗ࡟㔜せ࡞ㄢ㢟࡜࡞ࡗ࡚࠸ࡿࠋ
ᡃࠎࡣࠊ2010 ᖺ A ᮇ࡟ᘬࡁ⥆ࡁࠊ◳ X ⥺ග㟁Ꮚศග㻔HAXPES㻕࡟ࡼࡿ GaN/SiNx ⏺㠃≧ែศᯒࢆ⾜ࡗࡓࠋ௒ᅇࡣࠊ≉࡟ࢳ࣮ࣕࢪ࢔ࢵࣉ⿵ṇἲ࡟ࡘ࠸࡚ヲࡋࡃ᳨ウࡋࡓୖ࡛ࠊ࢔ࢽ࣮ࣝࡢ᭷↓࡟ࡼࡿ⏺㠃≧ែࡢኚ໬࡟ࡘ࠸࡚ㄪᰝࢆ⾜ࡗࡓࠋᐇ㦂㸸ᅗ 1 ࡟ヨᩱ᩿㠃ࡢᵓ㐀ᶍᘧᅗࢆ♧ࡍࠋヨᩱ#1 ࡣࠊ࢟ࣕࣜ࢔⃰ᗘ 51016/cm3 ࡢ n-GaN ⾲㠃ࢆ O2ࣉࣛࢬ࣐ฎ⌮ࡋࡓᚋࠊࣉࣛࢬ࣐ CVD ࡛ཌࡳ⣙ 4nm ࡢ SiNx ⭷ࢆሁ✚ࡋࡓࡶࡢ࡛࠶ࡿࠋヨᩱ#2 ࡛ࡣࠊ᭦࡟㧗 ࡛ࡢ࢔ࢽ࣮ࣝࢆ㏣ຍࡋ࡚࠸ࡿࠋ࢔ࢽ࣮ࣝ᮲௳ࡣࠊ ᗘ>600Υࠊ㑏ඖ㞺ᅖẼ୰㸦ࣉࣟࢭࢫ᫬㛫㹼⣙ 15 ศ㸧࡜ࡋࡓࠋ࡞࠾ࠊࢳ࣮ࣕࢪ࢔ࢵࣉᢚไࡢࡓࡵࠊヨᩱ⾲㠃࡟ࡣཌࡳ 3 nm ࡲࡓࡣ 6 nm
ࡢ AuPd ྜ㔠ࢆ⵨╔ࡋࡓࠋ
HAXPES ᐃࡣࠊSPring-8 ࡢ BL46XU ࡟࡚ᐇ᪋ࡋࡓࠋບ㉳ X ⥺࢚ࢿࣝࢠ࣮ࡣ 7.9keVࠊග㟁Ꮚྲྀฟ
ࡋゅ㻔TOA㻕ࡣ 80r࡜ 30rࡢ 2 Ỉ‽࡛⾜ࡗࡓࠋග㟁Ꮚ᳨ฟ࡟ࡣ༙⌫ᆺ㟁Ꮚ࢔ࢼࣛ࢖ࢨࢆ⏝࠸ࠊ50meVࢫࢸࢵࣉ࡛ࢫ࢖࣮ࣉࢆ⾜ࡗࡓࠋ ᐃࡣࠊGa2p ࡞࡝ࡢ௚ࠊࢳ࣮ࣕࢪ࢔ࢵࣉ⿵ṇࢆ┠ⓗ࡜ࡋ࡚ AuPd ୰ࡢ Au4f ࡟ࡘ࠸࡚ࡶ⾜ࡗࡓࠋᅗ 1㸬ศᯒ⏝ヨᩱࡢ᩿㠃ᵓ㐀⤖ᯝ࠾ࡼࡧ⪃ᐹ㸸
㻔1㻕ࢳ࣮ࣕࢪ࢔ࢵࣉ⿵ṇ
ࡲࡎࠊAuPd ࡢ ᐃ⤖ᯝ࡟ࡘ࠸࡚ヲࡋࡃ᳨ウࡋࡓࠋᮏ◊✲ࡢ AuPd ྜ㔠ࡣ Pd ⃰ᗘࡀ 40%࡜኱ࡁࡃࠊ༢యࡢ Au ࡟ẚ࡭࡚໬Ꮫࢩࣇࢺࢆ
ᣢࡗ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡗࡓࠋࡑࡇ࡛ࠊᅗ 2 ࡢ
ࡼ࠺࡟ Au ࡜ AuPd ࡀྠ㟁఩࡜࡞ࡿࡼ࠺࡞ཌ⭷ࡢ✚ᒙヨᩱࢆู㏵స〇ࡋࠊ㏻ᖖࡢග㟁Ꮚศග⿦⨨࡛ Au4f ࡢ ᐃࢆ⾜ࡗ࡚࠸ࡿࠋࡑࡢ⤖ᯝࠊAuPd ࡣ Au ࡟ᑐࡋࠊప࢚ࢿࣝࢠ࣮ഃ࡟
0.394 eV ࡢ໬Ꮫࢩࣇࢺࢆᣢࡘࡇ࡜ࡀศ࠿ࡗࡓࠋ
༶ࡕࠊAu㸻84 eV ࡜ࡋ࡚ࠊAuPd㸻83.606 eV࡟࡞ࡿࠋᅗ 3 ࡣࠊHAXPES ヨᩱ࡟⵨╔ࡋࡓ AuPd ࡢAu4f ࢫ࣌ࢡࢺࣝᐇ ౛࡛࠶ࡿࠋẚ㍑ࡢࡓࡵࠊAu ᶆ‽ヨᩱࡢࢫ࣌ࢡࢺࣝࠊཬࡧࠊ
ୖグࡢ AuPd
㸻83.606 eV ࡢࣆ࣮ࢡ఩⨨ࡶేグࡋ࡚࠶ࡿࠋཌ
ࡳ 3 nm ࡢ AuPd ࡛ࡣࠊᮏ᮶ࡢࣆ࣮ࢡ఩⨨࡛࠶
ࡿ 83.606 eV ࠿ࡽࠊ⣙ 0.7 eV 㧗࢚ࢿࣝࢠ࣮ഃ
࡟ࢩࣇࢺࡋ࡚࠸ࡿࠋ୍᪉ࠊཌࡳ 6 nm ࡛ࡣࠊࢩࣇࢺࡣ 0.1eV ⛬ᗘ࡛࠶ࡗࡓࠋ࡞࠾ࠊࢩࣇࢺ
㔞ࡣಶࠎࡢヨᩱ࡟ࡼࡗ࡚ᑡࡋࡎࡘ␗࡞ࡿࡶࡢࡢࠊᴫࡡྠᵝࡢ࡛ࣞ࣋ࣝ࠶ࡗࡓࠋ
⤖ㄽ࡜ࡋ࡚ࠊ3 nm ཌࡢ AuPd ࡛ࡣࢳ࣮ࣕࢪ࢔ࢵࣉ࡟ࡼࡿࢩࣇࢺࡀ㢧ⴭ࡛࠶ࡿࡢ࡟ᑐࡋࠊ
ྠ 6 nm ࡛ࡣ࠿࡞ࡾᢚไࡉࢀ࡚࠸ࡿ࡜ゝ࠼ࡿࠋ௨ୖࡼࡾࠊᮏ ᐃ࡟ࡣ AuPd ཌ㸻6 nm ࡢヨᩱࢆ⏝࠸ࡓࠋྛヨᩱࡢࢳ࣮ࣕࢪ࢔ࢵࣉ࡟ࡼࡿࢩ
ࣇࢺ࡟ࡘ࠸࡚ࡣࠊAuPd ୰ࡢ Au4f ࡀ 83.606 eV࡜࡞ࡿࡼ࠺࡟⿵ṇࢆ⾜ࡗࡓࠋ
㻔2㻕 Ga2p ࢫ࣌ࢡࢺࣝ
ᅗ 4 ࡟ Ga2p ࡢග㟁Ꮚࢫ࣌ࢡࢺࣝࢆ♧ࡍࠋ୧ヨᩱ࡜ࡶࠊTOA㸻80r࡜ 30rࡢࢫ࣌ࢡࢺࣝࢆ
㔜ࡡ࡚⾲♧ࡋ࡚࠶ࡿࠋゝ࠺ࡲ࡛ࡶ࡞ࡃࠊ30rࢫ
࣌ࢡࢺࣝࡢ᪉ࡀࠊヨᩱ⾲㠃ഃࡢᐤ୚ࡀ኱ࡁ࠸ࠋ
ࡲࡎࠊ#1㸦㸻࢔ࢽ࣮ࣝ࡞ࡋ㸧࡟ࡘ࠸࡚ࡣࠊ
80r࡟ẚ࡭ 30rࡢ᪉ࡀࠊࢃࡎ࠿࡞ࡀࡽ㧗࢚ࢿࣝࢠ࣮ഃ࡟ᗈࡀࡗ࡚࠸ࡿࡼ࠺࡟ぢ࠼ࡿࠋ୍᪉ࠊ#2㸦㸻࢔ࢽ࣮ࣝ࠶ࡾ㸧࡛ࡣࠊ80r࡟
ẚ࡭ 30rࡢ᪉ࡀప࢚ࢿࣝࢠ࣮ഃ࡟ࢸ࣮ࣝࢆᣢ
ࡗ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿࠋ
O2 ࣉࣛࢬ࣐ฎ⌮࡟ࡼࡾ GaN ⾲㠃࡟ࡣ Ga-O⤖ྜࡀ⏕ᡂࡋ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋࡲࡓࠊN ࡟ẚ࡭࡚ O ࡢ᪉ࡀ㟁Ẽ㝜ᛶᗘࡣ኱ࡁ࠸ࡇ࡜࠿ࡽࠊ
Ga-N ࡟ẚ࡭࡚ Ga-O ࡢ᪉ࡀ㧗࢚ࢿࣝࢠ࣮ഃ࡟
఩⨨ࡍࡿ࡜⪃࠼ࡽࢀࡿࠋ༶ࡕࠊ#1 ࡛ࡢ 30rࢫ࣌ࢡࢺࣝ࡟ぢࡽࢀࡿ㧗࢚ࢿࣝࢠ࣮ഃࡢᗈࡀࡾ
ࡣࠊGaN/SiNx ⏺㠃࡟Ꮡᅾࡍࡿ Ga-O ⤖ྜ࡛࠶ࡿ࡜⪃࠼ࡽࢀࡿࠋ
ḟ࡟ࠊ#2 ࡢࢸ࣮ࣝ࡟ࡘ࠸࡚⪃ᐹࡍࡿࠋGa-N

ᅗ 2㸬Au/AuPd ✚ᒙヨᩱ࡜ Au4f ග㟁Ꮚࣆ࣮ࢡ఩⨨㻤㻟㻚㻢㻜㻢㼑㼂㻌㻭㼡㻼㼐㻌㻌 㻔㻟㻌㼚㼙 ཌ㻕㻌㻤㻟㻚㻢㻜㻢㼑㼂㻌㻭㼡㻼㼐㻌㻌 㻔㻢㻌㼚㼙 ཌ㻕㻌㻌 ᅗ 3㸬AuPd ⵨╔⭷ࡢ Au4f ග㟁Ꮚࢫ࣌ࢡࢺࣝ㻌
ᅗ୰ࡢⅬ⥺ࡣࠊࣂࣝࢡࡢ Au ᶆ‽ヨᩱࡢࢫ࣌ࢡࢺࣝ㻳㼍㻞㼜㻌㻔㻏㻞㻙䜰䝙䞊䝹䛒䜚㻕㻌㻳㼍㻙㻺㻌㼀㻻㻭㻌㻩㻌㻤㻜㼻㻌㼀㻻㻭㻌㻩㻌㻟㻜㼻㻌㔠ᒓ≧ 㻳㼍㻌㻳㼍㻞㼜㻌㻔㻏㻝㻙䜰䝙䞊䝹䛺䛧㻕㻌㼀㻻㻭㻌㻩㻌㻤㻜㼻㻌㻳㼍㻙㻺㻌㼀㻻㻭㻌㻩㻌㻟㻜㼻㻌㻳㼍㻙㻻㻌㻌 ᅗ 4㸬SiN ⭷࡛⿕そࡉࢀࡓ GaN ࡢ Ga2p ග㟁Ꮚࢫ࣌ࢡࢺ

ࡼࡾࡶప࢚ࢿࣝࢠ࣮ഃ࡟఩⨨ࡍࡿ Ga ࡢ໬Ꮫ≧ែ࡜ࡋ࡚ࡣࠊ㔠ᒓ≧ Ga ࡀ࠶ࡿࠋࡑࡋ࡚ࠊ#1㸦㸻࢔ࢽ࣮ࣝ࡞ࡋ㸧࡟ࡣࠊࡇࡢప࢚ࢿࣝࢠ࣮ഃࡢࢸ࣮ࣝࡣ඲ࡃぢࡽࢀ࡞࠿ࡗࡓࠋᚑࡗ࡚ࠊࡇࡢ㔠ᒓ≧ Gaࡣ࢔ࢽ࣮ࣝ࡟ࡼࡗ࡚⏕ᡂࡋࡓ࡜⪃࠼ࡿࡢࡀጇᙜ࡛࠶ࡿ㻔ᅗ 5 ཧ↷㻕ࠋ⤖ㄽ࡜ࡋ࡚ࠊGaN/SiNx ⏺㠃࡟Ꮡᅾࡍࡿ Ga-O ⤖ྜࡣࠊ࢔ࢽ࣮ࣝ࡟ࡼࡿ O 㝖ཤ㸦༶ࡕࠊ㑏ඖຠᯝ㸧࡟ࡼࡗ࡚ࠊ㔠ᒓ≧ Ga ࡟ኚ໬ࡋࡓ࡜⪃࠼ࡽࢀࡿࠋ

ᅗ 5㸬࢔ࢽ࣮ࣝ࡟ࡼࡿ GaN/SiN ⏺㠃ࡢኚ໬௒ᚋࡢㄢ㢟㸸
௒ᅇࠊ࢔ࢽ࣮ࣝฎ⌮࡟ࡼࡗ࡚ SiNx/GaN ⏺㠃≧ែࡀ࡝࠺ኚ໬ࡍࡿ࠿ࡢ▱ぢࡀᚓࡽࢀࡓࠋࡇࡢ▱ぢࢆά࠿ࡋ࡚ࠊHEMT ฟຊపୗ⌧㇟ࡢ᭦࡞ࡿᢚไࢆᅗࡗ࡚࠸ࡃࠋཧ⪃ᩥ⊩㸸[1] S.C. Binari, K. Ikossi, J. A. Roussos, W. Kruppa, P. Doewon, H. B. Dietrich, D. D. Koleske, A.E.
Wickenden, R. L. Henry, IEEE Trans.Electron Devices,48, 465 㻔2001㻕.
[2] D. J. Meyer, J. R. Flemish and J. M. Redwing. Appl. Phys. Lett., 92, 193505 㻔2008㻕.