Download - Increased Pulse Rep. Rates for Solid State Thyratron ... Power... · Increased Pulse Rep. Rates for Solid State Thyratron Replacements John Waldron Silicon Power Corporation 280 Great

Increased Pulse Rep. Rates for Solid State Thyratron Replacements

John WaldronSilicon Power Corporation280 Great Valley PkwyMalvern, PA 19355

PPPS 2019 Orlando, FL 23-282 June, [email protected]

mailto:[email protected]


Outline

• Introduction to Solidtron’s Enabling Technology– Pulse discharge targeted designs

• Solidtron Performance– Discharge Performance

– Increased Pulse Repetition Rate Strategy/Results

• Solid State Discharge Switch Replacements – Motivation

– Approach

– Experimental results

• Summary

• Questions

2


160,000 cells/cm2

SGTO

GTO

~ 50 cells /cm2

SGTO Advantages:

Cell structure 3000 x denser

Upper transistor >100x improved

• Forward drop greatly reduced

• Three times lower turn-off switching loss

Die sizes from 3x3mm to 15x22mm in 200mm IC foundry providing very high yield, repeatability and uniformity!

3

Super-GTO Vs. GTOSGTO is an IC foundry-fabricated GTO mated with Silicon Power’s proprietary low inductance ThinPak package

• Turn-on improved by 2 orders of magnitude

PPPS 2019 Orlando, FL 23-282 June, [email protected] 4

Solidtron: The Enabling Technology

Traditional thyristor design revisited, capturing IC house capability• Higher cell density improves current uniformity, drastically improving Τ𝑑𝑖

𝑑𝑡 capability• Upper base doping profile improved for higher gain • Metal interconnects improved, increased upper transistor gain and electrode bonding

area

IC Foundry Solidtron Cell

GTO Versus Solidtron, Fundamental Differences


Solidtron Advantages

• Cell density further enhanced

• Emitter area maximized

• Internal metal interconnect density improved

• Upper transistor gain further improved

• Increased cathode bonding pad area

8 inch starting material and improved manufacturing process further improving yield while driving cost down

5

Solidtron Vs. Super-GTOSolidtron follows SGTO strategy, focusing on pulse discharge versus turn-off applications


1600V Solidtron Product line:• Simple gating schemes (low power, easy isolation)• Unmatched Τ𝑑𝑖

𝑑𝑡 capability (>200kA/ms observed)• Easily implemented in series/parallel configurations

6

Solidtron Performance: Hyper-Fast

Capacitor Voltage (Ch2 Max Ref only)

Anode Current 3kA IPK

160ns ½ period

170ns ½ cycle ring down – Yellow = Anode Current, Cyan = Capacitor Voltage

Turn-on delay <90ns

Jitter <500ps

Fall time <40ns

di/dt >200kA/ms


Solidtron Performance: Hyper-Fast

7

550ns ½ pulse width ring down

1ms ½ pulse width ring down

Solid state discharge switch offers:• Rugged yet simple gate trigger• Repeatable fabrication and performance• Bidirectional current flow capability• Very high MTBF, minimizing down time

Ipk 1.8kA

Ipk 1.1kA

Hyper-Fast 1600V Solidtron Discrete products

Available in:• TO-247 • TO-264• Custom SMT packages


Solidtron: Increased Switching Speed

Punch-through design:• Higher BV for given device thickness• Allows bipolar current conduction• Improves turn-on speed• Reduces commutation time

Lower-base width and doping concentration determines BV


Solidtron: Increased Switching Speed

One factor contributing to commutation time is stored charge remaining in lower-base• Thinner lower-base results in less stored charge • Thinner lower-base reduces distance required for diffused carrier to reach emitter

Physically narrower lower-base is employed

¼

Can be thinned after processing to reduce Ron

Implementing lower voltage devices improves commutation time


Post-Fabrication Speed Enhancement

1

10

100

1000

0 20 40 60 80 100 120

t-o

ff (

us)

Temp °C

Commutation Time vs T at 5kAcm-2

Dose 4

Dose 3

Dose 2

Dose 1

As

fab'd

1

10

100

1000

0 20 40 60 80 100 120

t-o

ff (

us)

Temp °C

Commutation Time vs T at 10kAcm-2

Dose 4

Dose 3

Dose 2

Dose 1

As

fab'd

Reducing Minority Carrier Lifetime:• Increases pulse repetition capability

• Decreases commutation time without the need for complicated gate drive

• Post-fabrication process• Enables 1 design to cover range of applications

• Low-cost, high-volume capable process• Demonstrated an 18x improvement in commutation

time at 110°C and 10kAcm-2

• Favorable tradeoff for Ron and ILeakage

12.5µs → 80kHz


Post-Fabrication Speed Enhancement

1.0E-02

1.0E-01

1.0E+00

1.0E+01

1.0E+02

0 1 2 3 4 5

Lea

kage

Cu

rren

t (µ

A)

Dose #

Leakage Current at 1500V

as fab'd 85°C as fab'd 110°C

1 85°C 2 85°C

1 110°C 2 110°C

3 85°C 3 110°C

4 85°C 4 110°C

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

200 400 600 800 1000 1200

R-o

n (

mO

hm

)

J (Acm-2)

Differential Resistance at 110°C Dose 4 Dose 3

Dose 2 Dose 1

As fab'd

Reducing Minority Carrier Lifetime Tradeoffs:• Lower base gain is reduced, ↑ RON

• Lower τ increases generation current (↑leakage)• However, small ↑RON (<2x) for almost 20x

improvement in pulse rep rate

0 1 2 3 4 5

Rel

ati

ve L

ifet

ime

(A.I

.)

Dose #

Relative Lifetime Vs Dose


Solid State Discharge SwitchesMotivation

• Compliance with RoHS • Eliminate conditioning requirements• Eliminate requisite heaters• Simplify gating

• Built in gating requires TTL/Optical trigger and DC power supply• Improve efficiency

• In both energy transfer and off-state conditions• Improve turn-on delay and jitter• Increase usable lifetime

• No terminal erosion• Eliminate liquid cooling requirements• Increase mechanical installation flexibility• Improved performance over IGBT/SCR-based solid state switch replacements


Hyper-Fast Solid State Thyratron Replacement40kV SSTR-1 (Twin Stack)• Initial TO-247 version demonstrated 365k pulses

o 3kA, 300ns square wave

• Similar 20kV and 60kV derivatives planned to complete the product offering

• Negligible power dissipation in off-state (snubber resistors much higher in value)

• TO-264 version offers up to 30x increase in action

TO-247: SP245-03TO-264: SP275-02


Solid State Thyratron Replacement

40kV SSTR-1 (Twin Stack) Vs. e2v CX2282

Hyper-Fast 1600V Solidtron

• Τ𝑑𝑖𝑑𝑡 capability is >200kA/mSec

• Fiber Optically Triggered

• Small size - 9” Tall, 3.75” Base diameter

• Voltage capability of 40kV

• Yellow - 4.7kA Peak Current w/average Τ𝑑𝑖

𝑑𝑡 of ~60kA/mSec(Circuit Limited)

• Magenta - 36kV Discharge

Anode Current

Capacitor Voltage (Ch2 Max Ref only)

50nSec rise timePeak I >4kARep Rate = 100PPS


Summary

15

• RoHS compliance

• Unparalleled solid state Τ𝑑𝑖𝑑𝑡 capabilities

– Hyper-fast demonstrated 200kA/ms

• 𝑓(𝑖 𝑡 , 𝜏) capability, determined by experimental and/or sim data exceeds most if not all commercially available gas or solid state thyratrons available

• Designed with modular, scalable sub-assemblies

– Enables fitment for most thyratron or ignitron applications

Download - Increased Pulse Rep. Rates for Solid State Thyratron ... Power... · Increased Pulse Rep. Rates for Solid State Thyratron Replacements John Waldron Silicon Power Corporation 280 Great

Top Related