公开(公告)号：US11948769B2

公开(公告)日：2024-04-02

申请号：US18261645

申请日：2023-01-12

Applicant: Applied Physics Technologies, Inc.

Inventor： Gerald G. Magera ,  Aaron M. Torok ,  Joel A. Wenrich ,  Matthew C. Zappe

IPC: H01J1/16 ,  H01J9/04 ,  H05B3/14

CPC classification number: H01J1/16 ,  H01J9/042 ,  H05B3/145

Abstract: A monolithic graphite heater for heating a thermionic electron cathode includes first and second electrically conductive arms, each one of the first and second electrically conductive arms having an electrode mount at a proximal end, a thermal apex at a distal end, and a transitional region between the electrode mount and the thermal apex; a cathode mount electrically and mechanically coupling each thermal apex to form a maximum Joule-heating region at or adjacent the cathode mount and decreasing Joule heating along each transitional region; and a press-fit aperture formed in the cathode mount, the press-fit aperture sized to receive at least a portion of the thermionic electron cathode for facilitating thermionic emission produced therefrom in response to operative heat power generation provided by the maximum Joule-heating region.

公开(公告)号：US09490098B1

公开(公告)日：2016-11-08

申请号：US14992870

申请日：2016-01-11

Applicant: Applied Physics Technologies, Inc.

Inventor： William A. Mackie ,  Gerald G. Magera

IPC: H01J1/146 ,  H01J1/148 ,  H01J19/10 ,  H01J1/14

CPC classification number: H01J1/148 ,  H01J1/14 ,  H01J1/146 ,  H01J19/10 ,  H01J37/06 ,  H01J2201/196 ,  H01J2201/2889 ,  H01J2201/30484 ,  H01J2201/317 ,  H01J2237/06316

Abstract: An electron source is made from mixed-metal carbide materials of high refractory nature. Producing field-enhanced thermionic emission, i.e., thermal-field or extended Schottky emission, from these materials entails the use of a certain low work function crystallographic direction, such as, for example, (100), (210), and (310). These materials do not naturally facet because of their refractory nature. The disclosed electron source made from transition metal carbide material is especially useful when installed in a scanning electron microscope (SEM) performing advanced imaging applications that require a high brightness, high beam current source.

Abstract translation: 电子源由具有高耐火性质的混合金属碳化物材料制成。 从这些材料产生场强增强的热离子发射，即热场或延伸的肖特基发射需要使用某种低功函数的晶体学方向，例如（100），（210）和（310） 。 这些材料由于其耐火性质而不自然而然。 所披露的由过渡金属碳化物材料制成的电子源在安装在需要高亮度，远光束电流源的先进成像应用的扫描电子显微镜（SEM）中是特别有用的。

公开(公告)号：US09240301B1

公开(公告)日：2016-01-19

申请号：US13851732

申请日：2013-03-27

Applicant: Applied Physics Technologies, Inc.

Inventor： William A. Mackie ,  Gerald G. Magera

IPC: H01J1/14 ,  H01J1/146 ,  H01J19/10 ,  H01J1/148

CPC classification number: H01J1/148 ,  H01J1/14 ,  H01J1/146 ,  H01J19/10 ,  H01J37/06 ,  H01J2201/196 ,  H01J2201/2889 ,  H01J2201/30484 ,  H01J2201/317 ,  H01J2237/06316

Abstract: An electron source is made from mixed-metal carbide materials of high refractory nature. Producing field-enhanced thermionic emission, i.e., thermal-field or extended Schottky emission, from these materials entails the use of a certain low work function crystallographic direction, such as, for example, (100), (210), and (310). These materials do not naturally facet because of their refractory nature. The disclosed electron source made from transition metal carbide material is especially useful when installed in a scanning electron microscope (SEM) performing advanced imaging applications that require a high brightness, high beam current source.

Abstract translation: 电子源由具有高耐火性质的混合金属碳化物材料制成。 从这些材料产生场强增强的热离子发射，即热场或延伸的肖特基发射需要使用某种低功函数的晶体学方向，例如（100），（210）和（310） 。 这些材料由于其耐火性质而不自然而然。 所披露的由过渡金属碳化物材料制成的电子源在安装在需要高亮度，远光束电流源的先进成像应用的扫描电子显微镜（SEM）中是特别有用的。

公开(公告)号：US12237138B2

公开(公告)日：2025-02-25

申请号：US18596561

申请日：2024-03-05

Applicant: Applied Physics Technologies, Inc.

Inventor： Gerald G. Magera ,  Aaron M. Torok ,  Joel A. Wenrich ,  Matthew C. Zappe

IPC: H01J1/16 ,  H01J9/04 ,  H05B3/14

Abstract: A monolithic graphite heater for heating a thermionic electron cathode includes first and second electrically conductive arms, each one of the first and second electrically conductive arms having an electrode mount at a proximal end, a thermal apex at a distal end, and a transitional region between the electrode mount and the thermal apex; a cathode mount electrically and mechanically coupling each thermal apex to form a maximum Joule-heating region at or adjacent the cathode mount and decreasing Joule-heating along each transitional region; and a press-fit aperture formed in the cathode mount, the press-fit aperture sized to receive at least a portion of the thermionic electron cathode for facilitating thermionic emission produced therefrom in response to operative heat power generation provided by the maximum Joule-heating region.

公开(公告)号：US10083812B1

公开(公告)日：2018-09-25

申请号：US15359436

申请日：2016-11-22

Applicant: Applied Physics Technologies, Inc.

Inventor： William A. Mackie ,  Gerald G. Magera ,  Joshua M. Lovell

IPC: H01J1/304 ,  H01J9/02

CPC classification number: H01J1/3044 ,  H01J9/025 ,  H01J2201/30407 ,  H01J2201/30484 ,  H01J2209/0223

Abstract: An electron source emitter is made from transition metal carbide materials, including hafnium carbide (HfC), zirconium carbide (ZrC), titanium carbide (TiC), vanadium carbide (VC), niobium carbide (NbC), and tantalum carbide (TaC), which are of high refractory nature. Preferential evaporating and subsequent development of different crystallographic planes of the transition metal carbide emitter having initially at its apex a small radius (50 nm-300 nm) develop over time an on-axis, sharp end-form or tip that is uniformly accentuated circumferentially to an extreme angular form and persists over time. An emitter manufactured to the (110) crystallographic plane and operating at high electron beam current and high temperature for about 20 hours to 40 hours results in the (110) plane, while initially not a high emission crystallographic orientation, developing into a very high field emission orientation because of the geometrical change. This geometrical change allows for a very high electric field and hence high on-axis electron emission.