Resources Contact Us Home
Apparatus and method for uniform ion dose control

Image Number 5 for United States Patent #4816693.

A uniform ion implantation dose control apparatus controls the implantation of ion particles onto at least one wafer mounted on a rotating disk in the pathway of the ion particle beam. A grounded scanning wire is repeatedly moved across the beam to produce an emission of secondary electrons which is linearly proportional to the beam particle current. The secondary electrons emitted are collected and formed into a current I.sub.s by a collector electrode. Portions of the current I.sub.s on the collector electrode are sampled. While the vacuum conditions within the beamline are good, the beams electrical current I.sub.FC is measured and the collector current I.sub.s sample is calibrated therewith so that when the beamline vacuum becomes a high pressure vacuum, additional collector current I.sub.s samples may be utilized to determine a theoretical beam current I which is a function of the beam particle current I.sub.p =I/q. This theoretical beam current I is utilized to move the rotating disk along a radial pathway perpendicular to the beam pathway at a velocity V which is proportional to the theoretical beam current I.

  Recently Added Patents
Printed circuit board including electromagnetic bandgap structure
Diagnostic data interchange
Control system for shifting an automatic transmission
Cryptography on a simplified elliptical curve
Gaming machine certificate creation and management
Pattern generation method and pattern generation program
  Randomly Featured Patents
Loadlock apparatus and structure for creating a seal between an elevator drive shaft and the loadlock chamber thereof
PH-sensitive polymeric micelles for drug delivery
Credit card security device
Combined sliding screen door pull with screen guard therefor
Apparatus for electric-discharge texturing of a roll
Stabilized topical pharmaceutical preparations
Liquid chromatograph and liquid chromatography
Large envelope on-edge stacking conveyor
Website advertising inventory