Wien filter with integrated vacuum pump

Patent metadata

Field	Value
Publication number	US-11056313-B1
Application number	US-202016904910-A
Country	US
Kind code	B1
Filing date	Jun 18, 2020
Priority date	Jun 18, 2020
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

An integral Wien filter and vacuum pump for separating charged particles or for orienting their spin direction while maintaining optimal beamline vacuum. The vacuum pump is an ion pump including one or more cylindrical Penning cells to trap and expel electrons. The Wien filter includes orthogonal electric and magnetic fields to direct particles with the desired speed through the device while deflecting particles at undesired speeds. The Wien filter includes two electrodes, one biased positive and one biased negative, a dipole magnet, and means for reversing polarity of the electrodes to flip the spin of the charged particles. Metal plates on either side of the Penning cells embed gas that is ionized by trapped electrons in the Penning cell thus creating vacuum by turning gas into solid. The two metal plates can be configured to obtain vacuum pumping via chemical gettering and for removal of noble gases.

First claim

What is claimed is:

1. A filter with integrated vacuum pump, comprising:
a Wien filter to orient the spin direction of a polarized electron beam;
an ion pump including a pair of electrodes, said electrodes including one or more cylindrical Penning cells to trap and expel electrons;
a means to apply a magnetic field parallel to the axes of each of the Penning cells to trap and expel electrons trapped in the Penning cells;
a means to apply an electric field to the Wien filter; and
metal plates on opposing sides of the Penning cells, the metal plates to embed gas ionized by trapped electrons in the Penning cells and create vacuum by turning gas into solid.

2. The filter with integrated vacuum pump of claim 1 , comprising at least one of said metal plates is constructed of titanium to provide vacuum pumping via chemical gettering.

3. The filter with integrated vacuum pump of claim 2 , comprising a second of said metal plates is a material selected from the group consisting of titanium and tantalum.

4. The filter with integrated vacuum pump of claim 1 , comprising:
a first of said metal plates is constructed of titanium to provide additional vacuum pumping via chemical gettering; and
a second of said metal plates is constructed of tantalum to provide pumping of noble gases.

5. The filter with integrated vacuum pump of claim 1 , wherein the Penning cells comprise a pump speed of at least 30 liters/second.

6. The filter with integrated vacuum pump of claim 1 , wherein the Penning cells provide optimized pumping when biased with positive voltage from 3 to 10 kV.

Assignees

• Jefferson Science Ass Llc

Inventors

• Poelker Bernard Matthew
• Serrano Gabriel Gerardo Palacios
• Garcia Carlos Hernandez

Classifications

• H01J49/288

  using crossed electric and magnetic fields perpendicular to the beam, e.g. Wien filter · CPC title

• H01J41/20

  using gettering substances · CPC title

• H01J2237/1825

  Evacuating means · CPC title

• H01J2237/057

  Energy or mass filtering · CPC title

• H01J37/18 Primary

  Vacuum locks {; Means for obtaining or maintaining the desired pressure within the vessel} · CPC title