Amtech TEMPRESS User manual

Process Manual
Tempress®Systems, Inc.
Process manual
M220.383.02 January 2004

TABLE OF CONTENTS
PROCESS MANUAL I
Preface ..................................................................................... V
Tempress documentation set.................................................................V
User Definition ......................................................................................VI
Notes, Cautions and Warnings ............................................................VII
Contents description ...........................................................................VIII
Revision History..................................................................................VIII
1. Introduction .......................................................................1-1
1.1 General..................................................................................... 1-1
1.2 Process engineer area description............................................ 1-2
2. Safety .................................................................................2-2
2.1 Emergency Off (EMO) .............................................................. 2-2
2.2 Alarm Signals............................................................................ 2-2
2.2.1 Buzzer / LED ............................................................. 2-2
2.2.2 Touchscreen.............................................................. 2-2
2.2.3 Light tower................................................................. 2-3
2.2.4 TSC Alarm menu....................................................... 2-3
2.3 Light tower signal description.................................................... 2-3
2.4 Toxic Material ........................................................................... 2-5
2.5 Safety measures....................................................................... 2-5
3. Process setup and acceptance.....................................2.5-1
3.1 Process recipe setup procedure ............................................ 3.1-1
3.1.1 Introduction............................................................. 3.1-1
3.1.2 6 steps to a process recipe..................................... 3.1-1
3.1.3 Recommended command sequence...................... 3.1-2
3.1.4 Modifying the default Tempress recipe................... 3.1-3
3.2 Process recipe startup and fine-tuning................................... 3.2-1
3.2.1 Introduction............................................................. 3.2-1
3.2.2 Prerequisites........................................................... 3.2-1
3.2.3 Initial settings.......................................................... 3.2-1

TABLE OF CONTENTS
PROCESS MANUAL II
3.2.4 Further fine-tuning .................................................. 3.2-2
3.3 Alarm handling with Branch and Abort commands ................ 3.3-1
3.3.1 Introduction............................................................. 3.3-1
3.3.2 Do nothing with an alarms...................................... 3.3-1
3.3.3 Handling alarms with the Branch command ........... 3.3-1
3.3.4 Handling alarms with the Abort command.............. 3.3-2
3.3.5 Recipe example: LPCVD Nitride abort recipe......... 3.3-3
3.4 Process acceptance conditions ............................................. 3.4-1
3.4.1 Introduction............................................................. 3.4-1
3.4.2 Default process test conditions............................... 3.4-4
4. Process description..........................................................4-1
4.1 Nitride from NH3and SiH2Cl2................................................. 4.1-1
4.1.1 Basic configuration ................................................. 4.1-1
4.1.2 Description.............................................................. 4.1-1
4.1.3 Process result indication......................................... 4.1-2
4.1.4 Startup parameters for processing.......................... 4.1-2
4.1.5 Recommended cleaning interval ............................ 4.1-3
4.1.6 Gas schematic example: LPCVD siliconnitride....... 4.1-4
4.1.7 Recipe example: LPCVD siliconnitride from SiH2Cl2and
NH34.1-5
4.1.8 Troubleshooting a standard-nitride process............ 4.1-8
4.1.9 NH4Cl vapor pressure curve................................... 4.1-9
4.2 Flat Polycrystalline Si from SiH4............................................. 4.2-1
4.2.1 Basic configuration ................................................. 4.2-1
4.2.2 Description.............................................................. 4.2-1
4.2.3 Process result indication......................................... 4.2-2
4.2.4 Startup parameters for processing.......................... 4.2-2
4.2.5 Recommended cleaning interval ............................ 4.2-2
4.2.6 Gas schematic example: LPCVD Flat poly............. 4.2-4
4.2.7 Recipe example: LPCVD Flat poly-silicon from SiH44.2-
5
4.2.8 Troubleshooting a flat poly process........................ 4.2-8

TABLE OF CONTENTS
PROCESS MANUAL III
4.3 Silicondioxide (LTO SiO2) from SiH4and O2.......................... 4.3-1
4.3.1 Basic configuration ................................................. 4.3-1
4.3.2 Description.............................................................. 4.3-1
4.3.3 Startup parameters for processing.......................... 4.3-2
4.3.4 Recommended cleaning interval ............................ 4.3-2
4.3.5 Process result indication......................................... 4.3-3
4.3.6 Gas schematic example: LPCVD LTO.................... 4.3-4
4.3.7 Recipe example: LPCVD silicondioxide from LTO SiH4
and O24.3-5
4.3.8 Troubleshooting an LTO process ........................... 4.3-8
5. Operation Instructions...................................................4.3-1
5.1 Load or Unload process wafers............................................. 5.1-1
5.1.1 Load process wafers............................................... 5.1-1
5.1.2 Unload wafers......................................................... 5.1-1
5.2 Login TSC-2........................................................................... 5.2-1
5.2.1 TSC-2..................................................................... 5.2-1
5.3 Selecting a new process recipe ............................................. 5.3-1
5.3.1 Touchscreen........................................................... 5.3-1
5.3.2 TSC-2..................................................................... 5.3-3
5.4 Start/Continue a new process recipe..................................... 5.4-1
5.4.1 Touchscreen........................................................... 5.4-1
5.4.2 TSC-2..................................................................... 5.4-2
5.5 Stop a running process recipe ............................................... 5.5-1
5.5.1 Touchscreen........................................................... 5.5-1
5.5.2 TSC-2..................................................................... 5.5-2
5.6 Abort a running process recipe.............................................. 5.6-1
5.6.1 Touchscreen........................................................... 5.6-1
5.6.2 TSC-2..................................................................... 5.6-2
5.7 Edit ‘Variable Process Command’.......................................... 5.7-1
5.7.1 Touchscreen........................................................... 5.7-1
5.7.2 TSC-2..................................................................... 5.7-3

TABLE OF CONTENTS
PROCESS MANUAL I
V
5.8 Clear Alarms.......................................................................... 5.8-2
5.8.1 Required action....................................................... 5.8-2
5.8.2 Touchscreen........................................................... 5.8-2
5.8.3 TSC-2..................................................................... 5.8-3
5.9 Write/Edit process recipe....................................................... 5.9-2
5.9.1 Touchscreen........................................................... 5.9-2
5.9.2 TSC-2..................................................................... 5.9-3
5.10 Edit graphical image............................................. 5.10-2
5.10.1 Touchscreen......................................................... 5.10-2
5.10.2 TSC-2................................................................... 5.10-2
5.11 Logging process data ........................................... 5.11-2
5.11.1 TSC-2 (only) ......................................................... 5.11-2

PREFACE
PROCESS MANUAL
V
Preface
This set of manuals explains how to operate and maintain a Horizontal Diffusion/LPCVD
furnace.
Refer to the Touchscreen reference manual (M440.00) or the TSC-2 reference manual
(M450.00) for a full description of all operating screens.
For information about maintenance, refer to the maintenance manual (M230.00).
The Tempress Horizontal Diffusion Furnaces are fully described in the reference manuals
(M300.00).
Tempress documentation set
The complete Tempress documentation set includes:
• Safety manual
• Operator manual
• Reference manuals
1. Loadstation
2. Furnace
3. Gas cabinet
4. Main Power cabinet
5. DPC (Digital Process Controller)
6. DTC (Digital Temperature Controller)
7. ETC (Excess Temperature Controller)
8. Touchscreen
9. TSC-2 (+ SECS/GEM)
• Vendor documentation
1. Digital pressure switch
2. Mass Flow Controllers
3. External torch controller (if used)

PREFACE
PROCESS MANUAL
V
I
User Definition
It is strongly recommended that all users first read this manual before starting any procedure.
To produce an accessible manual suiting on various responsibilities, Tempress defines the
following users:
Operator
The operator is handling the process from loading until unloading of the wafers. Therefore
the operator needs to select a recipe, put the wafers on the boat, fill in Lot ID, Start the
process and monitor the progress using the Touchscreen and/or TSC-II.
Process engineer
The process engineer is a qualified chemical engineer, who is responsible for the process
recipes and their results. The process engineer writes, tests and releases new process recipes.
Service or Maintenance engineer
The maintenance engineer is a qualified electrician or mechanic, who is responsible for a
proper functioning system in accordance to its designated purpose. A Tempress qualified
service engineer will perform the first installation.

PREFACE
PROCESS MANUAL
Notes, Cautions and Warnings
Notes, Cautions and Warnings appear throughout this manual, where extra attention is
required to a particular (safety) item. Three levels can be distinguished:
)
NOTE
Notes alert to pay attention to items or procedures of special importance.
CAUTION
Cautions alert for a potentially hazardous situation that may result in minor
or moderate injuries.
Cautions can also alert for potential equipment and/or product damage.
WARNING
Warnings alert for conditions that may result in permanent and/or lethal
injuries.
V
II

PREFACE
PROCESS MANUAL
V
III
Contents description
This manual is divided into the following sections and appendices:
Section 1 Introduction
Provides an overview of the Tempress Systems Inc.
Horizontal furnace, what it is and what it can do.
Section 2 Safety
Describes the safety components and functions. It describes all measures
that are required to provide a safe way of working.
Section 3 Process setup and acceptance
Describes the basis of how to setup a process recipe and how to handle
alarms that are generated during the process. Finally all minimal process
requirements for acceptable process results are defined in process
acceptance.
Section 4 Process description
Contains specific process information including chemicals used, start-up
parameters and a basic recipe layout.
Section 5 Operation Instruction
Describes all procedures that are required for the process engineer.
Revision History
This manual is revision 0 of the Process Manual and is intended to explain the required
procedures. The function and screens it describes are based on the following software
releases:
• TSC 2 version 6.0 (17-02-2003)
• DPC 2.I.03 (17-02-2003)
• DTC 2.F.02 (17-02-2003)
• Touchscreen 2.I.05 (17-02-2003)
For minor software and hardware changes, addendum to this manual will be available. For
major changes, a new revision will be available. For price information or other questions
please contact Tempress Systems Inc.

INTRODUCTION
PROCESS MANUAL
1.Introduction
1.1 General
The horizontal furnaces of Tempress Systems Inc. are developed according to the latest
European directives for Machinery (98/37/EC), Low Voltage (73/23/EC) and EMC
(89/336/EEC).
The Tempress Diffusion system is a modular horizontal furnace designed to process (silicon)
wafers as part of the manufacturing technology of semiconductor, optical, MEMS and solar
devices.
Figure 1-1 shows an example of a L-shape diffusion system with 4 process tubes shown
without the partition of a cleanroom wall.
It is a right-handed system, defined according to the position of the furnace relative to an
operator.
Usually the system contains more than 1 tube. Based on the number and size of tubes, the
system is referred to as a 2, 3 or 4 stack.
Figure 1-1 is an example of a 4-stack system, allowing up to 4 different processes at any time.
The tubes are numbered from 1 to 4, with tube number 1 at the top and tube 4 at the
bottom. All tubes operate fully independently.
Main Power Cabinet
Figure 1-1 Schematic view of a right-handed 4-stack Diffusion System
1-1

INTRODUCTION
PROCESS MANUAL
1.2 Process engineer area description
H SOT URFACE
1-2
Figure 1-2 Loadstation
The process engineer area is limited to the loadstation only. Figure 1-2 shows all relevant
items.
The Loadstation part of a Tempress System should be placed in the cleanroom. The Furnace
and Gas cabinet can optionally be placed in the greyroom.
To load wafers, several loader types can be implemented, including the (default) inline loader,
the Amtech Atmoscan®and the backmounted softlander. To prevent particles on the wafers
during the loading process, a constant horizontal laminar flow is created from the loadstation
into the cleanroom.
The loadstation is powered by 230V and has an illuminated On/Off switch for the fans and
the lights.
The remote control cabinet in the loadstation contains TFT-Touchscreens, one for each
tube. These are the user interface for communication with the Digital System Controllers
(DPC, DTC and DMC).
MOVING PART
W
afers
Buzzer
/
LED
T
ouchscreen
Light/Fan Switch

SAFETY
PROCESS MANUAL
2.Safety
This section contains a brief description of the safety features of a Tempress Horizontal
Diffusion System for the process engineer.
Process engineers must have a general knowledge of the technology involved in diffusion
systems. They should understand safety practices outlined in this manual. Process engineers
must have additional knowledge about chemistry and chemicals used in the customer specific
process applications.
The descriptions contained in this user manual are general in nature. The actual furnace may
differ in minor detail from the furnace described in this manual, because of customer specific
requirements or modifications. Please refer to the Tempress Safety manual (M110.00) for a
complete description of available safety features.
2.1 Emergency Off (EMO)
Emergency Off (EMO) buttons are located around the system at accessible locations
according to EN 60204-1 especially EN 418. Pressing an EMO button turns off all power to
the system except to the fans on top of the furnace. This prevents fire hazard as a result of
high heat concentration in the furnace cabinet. Also those parts that are connected to a UPS
facility remain operational.
Press the EMO button when a person is in danger, when there is a fire, a water leak
or any other event that could be hazardous to life.
2.2 Alarm Signals
Alarms and alerts generated by tube controls are presented in several ways:
• Buzzer / LED
• Touch screen
• Light tower
• TSC-II
2.2.1 Buzzer / LED
Visible and audible alarm signals are generated by the process controller (DPC) and the
temperature controller (DTC). The visible signals will be presented with a LED, located
below the buzzer position as shown in Figure 1-1. Each process is represented by one LED
and buzzer combination.
2.2.2 Touchscreen
The visible alarms will be presented on the
touchscreen bottom line. Alarms on the
Touchscreen are always in combination with an
audible signal.
2-2
Touching the screen deactivates the audible signal.

SAFETY
PROCESS MANUAL
2.2.3 Light tower
Alarms generated by the DPC, DTC and DMC will be made visible by three colors. Each
color of the light tower represents particular circumstances.
- Green represents safe, operational condition.
- Yellow represents warnings and alerts
- Red represents alarms
See section 2.3 for a full description.
2.2.4 TSC Alarm menu
Activating the alarm menu gives an overview of all active and passed
alarms during the process. In case of an active alarm the “Alarm”
button start flashing on and off.
2.3 Light tower signal description
Two light towers, one on top of the loadstation in the
cleanroom and one on top of the furnace in the greyroom, are
installed for fast anticipation on the status of the (production)
process. This section describes the function of each light and its
relation to the tube status.
Red
Y
ellow
Green
A light tower is (default) comprised of 3 lights: from top to
bottom RED, YELLOW and GREEN.
The green light can indicate 2 signals:
1) OFF
2) ON
The yellow and red light can indicate 2 signals:
1) OFF
2) BLINK
Figure 2-1 Default light tower configuration
The light tower is controlled by a tower signal PLC that receives its commands from the
various controllers, among others DPC/DTC/DMC, Excess temperature controller, gas
detection system alarm and the TSC Host control.
In case the EMO-switch is activated or a power failure occurs for more than 4 seconds, the
power supply to the furnace will stop and also the light tower will be off.
The tower signal PLC is programmed by Tempress Systems Inc. and is not adjustable by
customers.
Note: Per tube there are 2 PLC-Inputs available for customer specific applications, like H2
detection.
2-3

SAFETY
PROCESS MANUAL 2-4
For a functional description of the light tower signals see table 1:
Signal Mode Description
Green ON Operational No warnings or messages
OFF Not operational
Yellow BLINKING N2pressure-switch No N2gas flow detected
Air pressure switch No Air flow detected
Torch temp (750) The torch temperature has
to exceed 750oC
Torch Flame failure There is no flame, the H2
valve will be closed
Torch H2/O2ratio The H2/O2ratio exceeds
the safety value
Torch shell The skin temperature of the
torch is too high
Temperature sensor
powerpack
Temperature powerpack is
too high
Bubbler temp Bubbler temp is too high
Bubbler level Fluid level is too low
O
2- low O2 flow is too low
Exhaust (Low/High) Exhaust flow out of limits
Limit alarm (only if
programmed in the process
recipe)
Actual value is out of limits
Wait for operator (only if
programmed in the process
recipe)
Operator action is required
to continue
Process is finished
Boat manual Servo driver is in manual
mode
Maintenance mode Maintenance mode is
activated
OFF No alarm and/or alert
Red BLINKING Excess temperature
controller has been activated
Tube is overheated
(Optional)Leakage detection A gas or water leak has been
detected
OFF No alarm and/or alert No actual dangerous or
hazardous situation
Table 1 Light tower signal description

SAFETY
PROCESS MANUAL 2-5
2.4 Toxic Material
The process engineer, responsible for all process related activities, has to inform the operator
about the hazards of the process. See section 4 Process description or safety manual for a
complete description of all details.
2.5 Safety measures
Safety measures are indicated in the appropriate procedures.

PROCESS SETUP AND ACCEPTANCE
PROCESS MANUAL
3. Process setup and acceptance
3.1 Process recipe setup procedure
3.1.1 Introduction
The Tempress Systems, Inc. process controller, DPC, has some unique features that enable the user
to program any kind of process recipe in any way possible.
A process recipe is made of steps, and within one step several commands can be programmed.
The DPC is designed to execute commands in one particular step simultaneously. The sequence of
commands is therefor not important (except for “Branch on” and “Abort on “ alarm commands).
It is recommended, though, to use a consequent sequence to improve readability for the user.
3.1.2 6 steps to a process recipe
3.1.2.1 Step 1: Determine the required process temperature
The first step is to define the required process temperatures. These include the Load/Unload
temperature and the Process temperature(s).
Settings that need to be determined are the setpoint, the slope, the Hi and Low limits and the type
of temperature control (spike or paddle).
3.1.2.2 Step 2: Program the temperatures
The temperatures must be programmed in the DTC memory either using a touchscreen or using
the TSC-2 computer(s).
Touchscreen
2. certifications menu
2. temperature menu
2. normal temperature table
TSC-2
Recipes menu
Normal temperature menu
3.1.2.3 Step 3: Make temperature schematic
From the selected temperatures a schematic can be made that typically has the following shape:
3.1-1

PROCESS SETUP AND ACCEPTANCE
PROCESS MANUAL
3.1.2.4 Step 4: Make detailed schematic
The schematic can be split into different sections. Each section is going to represent one process
step. The detailed schematic typically has the following shape:
3.1.2.5 Step 5: Convert schematic to block diagram
The detailed schematic represents the individual steps that will be used in the process recipe. Each
step can also be presented in a block diagram with the following shape:
Step 0
Step 1
Step 2
3.1.2.6 Step 6: Fill in each block
Each block can now be programmed. It must be recognized that Step 0 (the first step) has some
unique properties that are not found in any other step:
1.'standby' step
2.selection of other recipe only here
3.must be started manually (no automatic continuation)
4.is the target for an Abort command
5.no time command available
6.no branch command available
7.no abort command available
3.1.3 Recommended command sequence
As stated previously, the DPC will execute all commands simultaneously, except for the
“Branch on” and “Abort on” instructions.
To improve readability the following sequence is recommended:
1.message
2.time
3.temperature
4.boat
3.1-2

PROCESS SETUP AND ACCEPTANCE
PROCESS MANUAL
3.1-3
5.analog out (MFCs)
6.digital out (valves)
7.alarm limits
8.alarm on digital inputs
9.branch on
10.abort on
11.wait for
12.abort recipe
As step 0 has been designed as the Standby step all commands in step 0 must be programmed
to create a safe condition.
This involves
closing all gas flows and valves , except for a small N2purge flow, setting a
low temperature and programming the boat in .
3.1.4 Modifying the default Tempress recipe
The default Tempress process recipe is designed with Step 0 as Standby for all atmospheric
processes. Obviously customers are free to alter the default recipe to fit their particular
needs. For example, a 24 hr production environment typically uses step 0 as Load/unload
step, not as a standby condition, because the machine is actually never in standby.
The transition is easy:
1) Modify the step 0 settings such that it contains:
1) Message Load/Unload with Sonalert
2) Boat out
3) Gas N2flow high
2) Remove step 1 Boat Out
3) Remove Step 2 Load Wafers

PROCESS SETUP AND ACCEPTANCE
PROCESS MANUAL
3.2-1
3.2 Process recipe startup and fine-tuning
3.2.1 Introduction
Process fine-tuning is required to reach the guaranteed process specifications and improve a current
process. Many different methods lead to the same process result and any approach is valid as long
as it satisfies the specifications. A few tips are described here that can be used as a guideline for
process fine-tuning.
3.2.2 Prerequisites
The following items are required before process fine-tuning can be started.
- a fully functional system (leaktested, profiled)
- a process recipe
- appropriate temperature recipes
3.2.3 Initial settings
The initial settings can be copied from an existing recipe if that is available. Alternatively, the
example recipes given later in this manual can be used. These recipes are based on a default system,
therefore the example recipes need to be adapted to fit the customer specific machine.
Two different process conditions occur. The atmospheric processes and the LPCVD processes.
3.2.3.1 Atmospheric process
- calculate the required gasflow to obtain a refresh interval of 3 minutes for process conditions
and 5 minutes for standby conditions. Take into account the tube volume and the gas
expansion at high temperatures. For example flows see Table 3-1, and keep in mind that at
1000oC a gas expands 4.7x (and 3.6x at 700oC)
- use a flat temperature
The flat temperature is sufficient for most atmospheric processes anyway (especially (dry and wet)
oxidations). A ramped temperature can be used later to counter the expected depletion effects that
will occur in the POCl3deposition and diffusion process.
The reason to start of with a flat temperature is to make sure the machine is performing as
expected (and therefore should give a depletion effect).
Table 3-1: Initial gas flows for atmospheric processes
Tube
length
[dm]
Tube ID
[dm]
Tube
volume
[liter]
MFC setting
[slm] for
700oC 5 min
MFC setting
[slm] for
1000oC 3 min
TS430x 13 1.6 26 1.5 1.9
TS460x 18 1.6 36 2.0 2.6
TS480x 20 1.6 40 2.3 2.9
TS4100x 25 1.6 50 2.8 3.6
TS630x 13 2.12 46 2.6 3.3
TS660x 18 2.12 64 3.6 4.5
TS680x 20 2.12 71 4.0 5.0
TS6100x 25 2.12 88 5.0 6.3
TS840x 13 2.7 74 4.2 5.3