Browse Prior Art Database

On Line Ion Implantation Dose Uniformity Monitor

IP.com Disclosure Number: IPCOM000084737D
Original Publication Date: 1975-Dec-01
Included in the Prior Art Database: 2005-Mar-02
Document File: 2 page(s) / 40K

Publishing Venue

IBM

Related People

Hammer, WN: AUTHOR

Abstract

This system provides a continuous topographical profile map of the accumulated ion implant dose across the target.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 58% of the total text.

Page 1 of 2

On Line Ion Implantation Dose Uniformity Monitor

This system provides a continuous topographical profile map of the accumulated ion implant dose across the target.

Monitoring of ion implantation is accomplished through the system illustrated by coupling pulses whose rate is proportional to beam current (as from a current integrator) with analog voltages representing the target (or beam) position, and by generating from them an address for use in a storage display unit. A suitable display unit is a multichannel analyzer. The integrator output pulses may also be used with a scaler to record the total ion dose.

The basic analog DC voltages proportional to target position are modified to represent the beam size relative to the total implant size, by superimposing on them a suitable waveform to produce on the display a representation analogous to the actual ion implant beam used. For the simple case of a uniform rectangular beam, these superimposed voltages are triangular waveforms. Suitably modified beam profile monitor signals may be used for more complicated beam shapes.

The composite waveforms are used as inputs to two analog-to-digital converters (ADC's), which are coincidence gated by the integrator output pulses whose rate is proportional to beam current.

The analog-to-digital converters generate binary-coded decimal addresses which represent the instantaneous position on the target at which the implantation is occurring. These addresses are used by the multich...