Annual Report Extention to PVSCAN

Artak HambarianNREL, August, 2007

Outline

The goal of the project Preliminary calculations (excel) Block diagram Components:

+ Mechanics; + Optics; + Analog Electronics; + Digital Electronics/Data Streaming;+ Motion Control;+ Software.

Providers Current Status

The goal of the project

To achieve rapid polar scanning of semiconductor wafers up to 300 mm (12”) in diameter for specularity detection with resolution of 10µ in the first phase, and 1-2µ in the second phase

In the second phase PL and OBIC can be added, Cartesian scan employed.

Preliminary calculations

Modes of polar scan: constant angular velocity (CAV); constant linear velocity (CLV).

CAV: the number of dots on ONE loop defines the data acquisition rate at a given rpm.

CLV: the number of dots on the LARGEST loop defines the data acquisition rate at a given rpm.

CAV and CLV

Number of points = N Number of points = N/2

Preliminary calculations (excel)

Wafer size, mm 300 300 300 RPM 3,000 3,000 3,000 Resolution, micron 10.0 3.3 1.1 Scan time, minutes 5.0 15.0 45.0 Total information, bytes 5,654,866,776 50,893,800,988 458,044,208,893 Information flow rate, 2 ch., B/s 9,424,778 28,274,334 84,823,002 Readout frequency, Hz 4,712,389 14,137,167 42,411,501

Preliminary calculations (excel) 2

Wafer size, mm 300 300 300 RPM 3,000 3,000 2,200 Resolution, micron 10.0 3.3 1.1 Scan time, minutes 5.0 15.0 61.4 Total information, bytes 5,654,866,776 50,893,800,988 458,044,208,893 Information flow rate, 2 ch., B/s 9,424,778 28,274,334 62,203,535 Readout frequency, Hz 4,712,389 14,137,167 31,101,767

Block Diagram

wafer

Spindle,

encoder

Optical probe

Linear stage, encoder, r Analog amplifier

Motion Control

ADC, Data streaming, PC, User

Innterface, Drivers,

VI-s.

Components

Mechanics: table, granite substrate, spindle, vacuum chuck, linear stage.

Optics: optical probe Motion Control: encoders, multipliers,

processor Analog Electronics: amplifiers Digital Electronics/Data Streaming: ADC-s,

Counter, Processor, PXI/…e. Software: User Interface, VI-s, drivers,

PC transformation, pattern recognition, storage management, etc.

Mechanics, requirements

Mechanical design

Mechanics: table support

Mechanics

Table:- designed by AUA and YPI;- to be manufactured by YPI

Other components: granite substrate, spindle, vacuum chuck, linear stage:- designed by AUA and YPI;- to be manufactured by AeroTech Inc, Pittsburg, PA.

Optics

Optical probe, in process, to be designed and manufactured by NREL.

Laser:- CW- Stability- Noise

Photodetectors (PD): low noise, high speed avalanche PD.

Analog Electronics: amplifiers

Thermal Stability Noise Input/output impedances to deal

with capacities of the photodiodes. Output impedances to deal with

ADC (50 input through coaxial cable.

Trans-Impedance Preamplifier

Motion Control, Data streaming, Synchronization

PX

I Express / P

XI

PXI ExpressController

NI PXIe-8105

PXI ExpressI/O Module

NI PXIe-6259

PXICounter Module

NI PXI-6602

PXIDigitizer Module 1

NI PXI-5142

PXIDigitizer Module 2

NI PXI-5142

Chassis NI PXIe-1062Q

Analogue Signal

AmplifierSignal 2.1

Signal 2.2

Signal 1.2

From4 PhotoSensors

Encoder Signal

Multiplier

Rotation

and

Radial

Motion

Systems

Pulses From RadialMotion System

Pulses FromRotation System

PMAC

Synch.and

Clocking

Signal 1.1

DAQ Start Pulse

DAQ Stop Pulse

24 Bit Coordinates

KeyboardMouseMonitor

PX

I Express / P

XI

PXI ExpressController

NI PXIe-8105

PXI ExpressI/O Module

NI PXIe-6259

PXICounter Module

NI PXI-6602

PXIDigitizer Module 1

NI PXI-5142

PXIDigitizer Module 2

NI PXI-5142

Chassis NI PXIe-1062Q

Analogue Signal

AmplifierSignal 2.1

Signal 2.2

Signal 1.2

From4 PhotoSensors

Encoder Signal

Multiplier

Rotation

and

Radial

Motion

Systems

Pulses From RadialMotion System

Pulses FromRotation System

PMAC

Synch.and

Clocking

Signal 1.1

DAQ Start Pulse

DAQ Stop Pulse

24 Bit Coordinates

KeyboardMouseMonitor

Motion Control Performs the displacement and takes the signal

about the displacement from encoders Provides displacement pulses at clock

frequency (40 MHz, through multiplier) and absolute coordinate at lower frequency (4 kHz).

Communicates through PCI or PXI bus. Performs backlash and other software driven

controls.

Data streaming

Analog to digital conversion (ADC) Counts of steps and synchronization Digital signal processing for:

- interleaving: omission of signals that do not carry information- on-fly pattern recognition (here or in the main processor)- laser noise cancelling- Other noise reduction algorithms (in process)

PX

I Express / P

XI

PXI ExpressController

NI PXIe-8105

PXI ExpressI/O Module

NI PXIe-6259

PXICounter Module

NI PXI-6602

PXIDigitizer Module 1

NI PXI-5142

PXIDigitizer Module 2

NI PXI-5142

Chassis NI PXIe-1062Q

Analogue Signal

AmplifierSignal 2.1

Signal 2.2

Signal 1.2

From4 PhotoSensors

Encoder Signal

Multiplier

Rotation

and

Radial

Motion

Systems

Pulses From RadialMotion System

Pulses FromRotation System

PMAC

Synch.and

Clocking

Signal 1.1

DAQ Start Pulse

DAQ Stop Pulse

24 Bit Coordinates

KeyboardMouseMonitor

PX

I Express / P

XI

PXI ExpressController

NI PXIe-8105

PXI ExpressI/O Module

NI PXIe-6259

PXICounter Module

NI PXI-6602

PXIDigitizer Module 1

NI PXI-5142

PXIDigitizer Module 2

NI PXI-5142

Chassis NI PXIe-1062Q

Analogue Signal

AmplifierSignal 2.1

Signal 2.2

Signal 1.2

From4 PhotoSensors

Encoder Signal

Multiplier

Rotation

and

Radial

Motion

Systems

Pulses From RadialMotion System

Pulses FromRotation System

PMAC

Synch.and

Clocking

Signal 1.1

DAQ Start Pulse

DAQ Stop Pulse

24 Bit Coordinates

KeyboardMouseMonitor

Data streaming

Data streaming

The sampling rate of analogue signals is assumed to be from 2.5Ms/sec to 40Ms/sec

ADC resolution is 14 bit, we use only 8 bit. for four sensors requires from

4x8bitx2.5Ms/sec = 80Mbit/sec to 4x8bitx40Ms/sec = 1.28Gbit/sec summary capacity of communication channel and signal processing speed

Data streaming

The system is based on PXI express / PXI components mounted into the NI PXIe-1062Q chassis

consists of:- two NI PXI-5142 digitizers, - NI PXI-6602 counter, - NI PXIe-6259 Input/Output module and - NI PXIe-8105 controller.

ADC-s, NI PXI-5142 digitizers

Each of the two digitizers receives two amplified analogue signals from photo sensors

On board signal processing

gain control, offset control, frequency translation, filtering, decimation and interleaving

On board DSP

The filtering is employed in level selection operation during the high precision scanning, which has the reason not to record the data points when scanned segment is clear from defects.

By choosing the threshold level equal to the background noise it will be possible to discard all not necessary sampled data points.

On board DSP

The interleaving process allows to combine the necessary data points into data packets by means of the initial buffering and then to transmit packets at lower data rate without transmission of zero information bytes.

It strongly decreases the data transmission rate through the PXIe/PXI bus

Synchronization - I/O PXIe-6259 module

Laser

CW Stability Noise Noise cancelling algorithm.

Software

User Interface Polar Cartesian transformation VI-s for interleaving On-fly pattern recognition and

indication Storage management (making

smaller files for storage) Simultaneous various size files

creation for easy zooming.

User Interface

System Integration

Excel