公开(公告)号：WO2005112128A3

公开(公告)日：2006-03-09

申请号：PCT/US2005014336

申请日：2005-04-26

Applicant: SILICONIX INC

Inventor： PATTANAYAK DEVA N ,  BAI YUMING ,  TERRILL KYLE ,  YUE CHRISTIANA ,  XU ROBERT ,  LUI KAM HONG ,  CHEN KUO-IN ,  SHI SHARON

IPC: H01L29/78 ,  H01L21/336 ,  H01L29/06 ,  H01L29/40 ,  H01L29/417 ,  H01L29/423

CPC classification number: H01L29/7813 ,  H01L29/0696 ,  H01L29/407 ,  H01L29/41741 ,  H01L29/4236 ,  H01L29/42368 ,  H01L29/42376 ,  H01L29/4238 ,  H01L29/66734

Abstract: In a trench MOSFET, the lower portion of the trench contains a buried source electrode, which is insulated from the epitaxial layer and semiconductor substrate but in electrical contact with the source region. When the MOSFET is in an "off" condition, the bias of the buried source electrode causes the "drift" region of the mesa to become depleted, enhancing the ability of the MOSFET to block current. The doping concentration of the drift region can therefore be increased, reducing the on-resistance of the MOSFET. The buried source electrode also reduces the gate-to-drain capacitance of the MOSFET, improving the ability of the MOSFET to operate at high frequencies. The substrate may advantageously include a plurality of annular trenches separated by annular mesas and a gate metal layer that extends outward from a central region in a plurality of gate metal legs separated by source metal regions.

Abstract translation: 在沟槽MOSFET中，沟槽的下部包含与外延层和半导体衬底绝缘但与源极区域电接触的掩埋源电极。 当MOSFET处于“关闭”状态时，掩埋源电极的偏置导致台面的“漂移”区域耗尽，增强了MOSFET阻止电流的能力。 因此，可以增加漂移区的掺杂浓度，从而降低MOSFET的导通电阻。 埋入式源极还降低了MOSFET的栅 - 漏电容，提高了MOSFET在高频下的工作能力。 衬底可以有利地包括由环形台面分隔开的多个环形沟槽和从源极金属区域分开的多个栅极金属腿中的中心区域向外延伸的栅极金属层。

公开(公告)号：WO03015180A2

公开(公告)日：2003-02-20

申请号：PCT/US0224782

申请日：2002-08-05

Applicant: SILICONIX INC

Inventor： DARWISH MOHAMED N ,  YUE CHRISTINA ,  GILES FREDERICK P ,  LUI KAM HONG ,  CHEN KUO-IN ,  TERRILL KYLE ,  PATTANAYAK DEVA N

IPC: H01L21/28 ,  H01L21/336 ,  H01L29/06 ,  H01L29/08 ,  H01L29/423 ,  H01L29/51 ,  H01L29/78

CPC classification number: H01L29/42368 ,  H01L21/28185 ,  H01L21/28194 ,  H01L29/0878 ,  H01L29/7813

Abstract: A trench MOSFET (40) includes active corner regions (25) and a thick insulative layer (33) centrally located at the bottom of the trench (19). A thin gate insulative layer (15) lines the sidewall and peripheral portion of the bottom surface of the trench (19). A gate (14) fills the trench, adjacent to the thin insulative layer (15). The gate (14) is adjacent to the sides and top of the thick insulative layer (33). The thick insulative layer (33) separates the gate (14) from the drain conductive region (13) at the bottom of the trench (19) yielding a reduced gate-to-drain capacitance and making the MOSFET (40) particularly suitable for high frequency applications.

Abstract translation: 沟槽MOSFET（40）包括中心位于沟槽（19）的底部的有源角区域（25）和厚绝缘层（33）。 薄栅绝缘层（15）将沟槽（19）的底表面的侧壁和周边部分排列。 栅极（14）填充与薄绝缘层（15）相邻的沟槽。 栅极（14）与厚绝缘层（33）的侧面和顶部相邻。 厚的绝缘层（33）在沟槽（19）的底部处将栅极（14）与漏极导电区域（13）分离，产生降低的栅极 - 漏极电容，并使MOSFET（40）特别适用于高 频率应用。