Data Generation for Fabricating Unique Chips Using a Charged Particle Multi-Beamlet Lithography System
Publication Date: 2017-Feb-15
The IP.com Prior Art Database
A computer-implemented method for generating beamlet control data (2009) for controlling a maskless pattern writer to expose a wafer for creation of electronic devices using a maskless lithographic exposure system using a maskless pattern writer such that exposure of the wafer according to the beamlet control data results in exposing a pattern having a different set of structures for different subsets of the electronic devices, the method comprising receiving design layout data (3021B) defining a plurality of structures for the electronic devices to be manufactured from the wafer; receiving selection data (2004) defining which of the structures of the design layout data are applicable for each electronic device to be manufactured from the wafer, the selection data defining a different set of the structures for different subsets of the electronic devices; and generating (3034) the beamlet control data based on the received design layout data and the received selection data.
DATA GENERATION FOR FABRICATING UNIQUE CHIPS USING A CHARGED
PARTICLE MULTI-BEAMLET LITHOGRAPHY SYSTEM
5  The invention relates to a computer-implemented method for generating beamlet
control data for controlling a maskless pattern writer to expose a wafer for creation of
electronic devices. The invention also relates to a computer-implemented method for
generating selection data used in the generation of the beamlet control data. More
specifically, the invention relates to the fabrication of unique chips using a charged particle
10 multi-beamlet lithography machine. The invention further relates to data processing systems,
computer program products and computer-readable storage media related to the computer
15  In the semiconductor industry, lithography systems are used to create, i.e. fabricate
such electronic devices, typically in the form of integrated circuits formed on silicon wafer,
commonly referred to as semiconductor chips. Photolithography utilizes reusable optical
masks to project an image of a pattern representing the desired circuit structures onto a
silicon wafer as part of the manufacturing process. The mask is used repeatedly to image the
20 same circuit structures on different parts of a silicon wafer and on subsequent wafers,
resulting in a series of identical chips being fabricated with each wafer, each chip having an
identical circuit design.
 In contemporary days, various technologies relating to data security, traceability,
and anti-counterfeiting create an increasing need for unique chips having unique circuits or
25 codes, or other unique hardware features for diversification of the chips. Such unique chips
are known and often implement a security related operation in an obfuscated manner
requiring the chip to be truly unique. The known unique chips are typically realized after the
manufacture of a chip, e.g. by manufacturing a series of identical chips using mask based
lithography and then, after manufacture, disrupting certain connections in the chip or by
30 assessing the uniqueness of the chip afterwards upon inspection and control of certain
features. The masks used in this process are expensive to produce, and manufacturing a
unique mask for each single chip is clearly much too expensive, for which reason mask based
photolithography is considered unsuitable for fabricating unique chips.
 Hence it has been suggested to utilize maskless lithography for the purpose of
creating unique chips. With maskless lithography no mask is used, and instead the required
5 pattern representing the circuit design is input to the maskless lithography system in the form
of a data file such as a GDSII or OASIS file containing the circuit design layout to be
transferred to the target, e.g. wafer, to be exposed by the maskless lithography system.
 A maskless lithography and data input system is disclosed in WO 2010/134026 in
the name of Applicant...