3 A/40 V新型肖特基勢壘二極管的設計與研制

王富強,馬行空,瞿宜斌

(93856部隊,甘肅 蘭州　730070)

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3 A/40 V新型肖特基勢壘二極管的設計與研制

王富強,馬行空,瞿宜斌

(93856部隊,甘肅 蘭州730070)

摘要為提高傳統肖特基二極管的擊穿電壓,減小了器件的漏電流,提高芯片利用率,文中設計研制了適合于裸片封裝的新型肖特基勢壘二極管(SBD)。利用Silvaco Tcad軟件模擬,在器件之間采用PN結隔離,器件周圍設計了離子注入形成的保護環,實現了在濃度和厚度分別為7.5×1012cm-3和5 μm的外延層上,制作出了反向擊穿電壓45 V和正向導通壓降0.45 V的3 A/45 V肖特基二極管,實驗和仿真結果基本吻合。此外,還開發了改進SBD結構、提高其電特性的工藝流程。

關鍵詞肖特基勢壘;結隔離;保護環;擊穿電壓

Design and Fabrication of 3 A/40 V Schottky Potential Barrier Diode

WANG Fuqiang,MA Xingkong,QU Yibin

(Troop 93856,PLA,Lanzhou 730070,China)

AbstractA novel Schottky potential barrier diode (SBD) suitable for die package has been successfully designed and fabricated to increase the breakdown voltage,decrease the leakage current and improve the utilization ration of chip area.The PN junction isolation is performed by simulation in Silvaco Tcad between devices surrounding which a protecting ring is designed using implantation technique.A 3 A/45 V Schottky diode with breakdown voltage of 45 V and forward voltage of 0.45 V was fabricated on 5 μm epitaxial layer doped at N-concentration of 7.5×1012cm-3.The simulated characteristics of SBD are verified by the measurement results.The structure and technological processes for improving the performances of SBD are also presented.

KeywordsSchottky potential barrier diode;junction isolation;protecting ring;breakdown voltage

隨著電子科技技術的不斷發展,電子產品更加小型化、便攜化。整機設計尺寸的變小,要求內部芯片占用比例縮小。傳統肖特基二極管陽極和陰極分別位于硅片兩側,芯片厚度較大,同時多個肖特基二極管串并聯占用空間較大。因此,在保證設計要求的前提下,采用肖特基二極管裸片封裝很有必要[1-4]。

本文設計和試制了反向擊穿電壓45 V和正向導通壓降0.45 V的肖特基二極管,提出了利用PN結隔離的方法。在同一個芯片內部集成多個靠近結終端處結構彼此基本相同、遠離終端處結構相似的肖特基二極管小單元(稱為元胞),各元胞之間利用結隔離的方法實現電學絕緣[5-7]。另外,利用穿通光刻工藝將二極管產品的負極引到正面,將正、負兩極間隔布置,做在芯片的同一平面上,減小了單個二極管的厚度,也便于多個晶體管連接,實現了整片封裝。……