Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Efficient Detector for Wafer Registration With X-Rays

IP.com Disclosure Number: IPCOM000060996D
Original Publication Date: 1986-Jun-01
Included in the Prior Art Database: 2005-Mar-09
Document File: 2 page(s) / 37K

Publishing Venue

IBM

Related People

Hinkel, H: AUTHOR [+4]

Abstract

The present invention concerns mask alignment, an aspect of X-ray lithography. An X-ray detector with a high quantum efficiency, integrated on the wafer and formed as a PIN (positive-intrinsic-negative) diode with a thick depletion layer, is described. X-ray lithography, one approach to future submicron technologies, although being known for its excellent resolution, tends to pose problems during mask alignment. Currently used light and electron optical methods are disadvantageous, particularly since the imaging characteristics of light or electrons may differ from those of X-rays. A wafer-integrated X-ray detector, such as that described in IBM Technical Disclosure Bulletin 19, 4441-4444 (April 1977), has a poor quantum efficiency resulting from the relatively great depth of penetration of the X-rays in the wafer.

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 71% of the total text.

Page 1 of 2

Efficient Detector for Wafer Registration With X-Rays

The present invention concerns mask alignment, an aspect of X-ray lithography. An X-ray detector with a high quantum efficiency, integrated on the wafer and formed as a PIN (positive-intrinsic-negative) diode with a thick depletion layer, is described. X-ray lithography, one approach to future submicron technologies, although being known for its excellent resolution, tends to pose problems during mask alignment. Currently used light and electron optical methods are disadvantageous, particularly since the imaging characteristics of light or electrons may differ from those of X-rays. A wafer-integrated X-ray detector, such as that described in IBM Technical Disclosure Bulletin 19, 4441-4444 (April 1977), has a poor quantum efficiency resulting from the relatively great depth of penetration of the X-rays in the wafer. Radiation-induced electron-hole pairs in an insulator of that detector are detected by means of an electric field (Figs. 1 and 2, where 18 is the mask, 19 the wafer, 20 the detector and 21 the thin insulating film generating a current proportional to the incident X-rays). For increasing the quantum efficiency, a PIN diode (Fig. 3) is integrated on the wafer across its entire width such that the depletion layer, in which the radiation-induced electron- hole pairs are formed, also extends across the entire wafer. The PIN diode is generated by depositing a P-layer 1 on the top side and an N-layer 2 on...