Ultra-Fast Solid State Replacement

John Waldron and Ken Brandmier Silicon Power Corporation 280 Great Valley Pkwy Malvern, PA 19355

[email protected] [email protected] ICOPS, Atlantic City, NJ May 23, 2017 Outline

• Overview of Solidtron’s Enabling Technology – Pulse discharge targeted designs • Solidtron Performance – Ultra-fast discharge capabilities – High action capabilities • Solid State Thyratron Replacements (SSTR) – Motivation – Approach – Performance – Experimental results • Summary • Questions

ICOPS, Atlantic City, NJ May 23, 2017 2 Super-GTO Vs. GTO

SGTO is an IC foundry-fabricated GTO mated with Silicon Power’s proprietary low ThinPak package

SGTO SGTO Advantages: Cell structure 3000 x denser

160,000 cells/cm2 Upper >100x improved • Forward drop greatly reduced • Three times lower turn- off switching loss • Turn-on improved by GTO 2 orders of ~ 50 cells /cm2 magnitude

Fabricated in 3.3 cm2 die in 6 inch silicon at very high yield, repeatability and uniformity!

ICOPS, Atlantic City, NJ May 23, 2017 3 Solidtron Vs. Super-GTO

Solidtron follows SGTO strategy, focusing on pulse discharge versus turn-off applications

Solidtron Advantages

• Emitter area maximized • Internal metal interconnect density improved • Upper transistor gain further improved • Increased bonding pad area

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

ICOPS, Atlantic City, NJ May 23, 2017 4 Solidtron: The Enabling Technology GTO Versus Solidtron, Fundamental Differences

IC Foundry Solidtron Cell

Traditional design revisited, capturing IC house capability 푑푖 • Higher cell density improves current uniformity, drastically improving Τ푑푡 capability • Upper base doping profile improved for higher gain • Metal interconnects improved, increased upper transistor gain and electrode bonding area ICOPS, Atlantic City, NJ May 23, 2017 5 Solidtron Performance: Ultra-Fast

1600V Solidtron Product line: • Simple gating schemes (low power, easy isolation) 푑푖 • Unmatched Τ푑푡 capability (>200kA/ms observed) • Easily implemented in series/parallel configurations • Efficient bidirectional current capability

Anode Current Turn-on delay <90ns 3kA IPK 160ns ½ period Jitter <100ps Fall time <40ns di/dt >100kA/ms (Ch2 Max Ref only)

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

ICOPS, Atlantic City, NJ May 23, 2017 6 Solidtron Performance: Ultra-Fast 550ns ½ pulse width ring down Solid state discharge offers: • Rugged yet simple gate trigger • Repeatable fabrication and performance • Bidirectional current flow capability • Very high MTBF, minimizing down time

Ipk 1.8kA

1ms ½ pulse width ring down

Ultra-Fast 1600V Solidtron Discrete products

Ipk 1.1kA Available in: • TO-247 • TO-264 • Custom SMT packages

ICOPS, Atlantic City, NJ May 23, 2017 7 Solidtron Performance: Ultra-Fast 4000V Solidtron Product line: • Maintains simple gating schemes 푑푖 • Τ푑푡 capability >100kA/ms • Bidirectional current capability • Offers more compact HV Thyratron replacements (fewer series levels)

32.4 kA ½ period 140ns Single 0.9”x0.6” chip (2cm2 active area), 6.5kV* die pulse discharge test: • 4kV Ultra-Fast 4.0-6.5kV • 45kA Ipk Solidtron Product Family • Bidirectional current flow 푑푖 • Τ푑푡 = 105kA/ms 45.4 kA Capacitor Voltage (Ch2 Max Ref only) *6.5kV BV, 4kV rating Ch1 (black) inverted Anode current 10kA/div Ch2 (green) Anode Voltage

ICOPS, Atlantic City, NJ May 23, 2017 8 Solidtron Performance: High Action 6.5kV High Action Solidtron Performance Single 0.9”x0.6” chip (1) 6.5kV Solidtron Cap Discharge (2cm2 active area), 6.5kV die 20.3 kA, 20.8 Vf pulse discharge test: W R~1m • >20kA peak capability • 20.8V forward drop • 1mW effective on-resistance • I2t capability > 10kA2s ~50ms 푑푖 Measured Τ푑푡 capability to 100kA/ms

ICOPS, Atlantic City, NJ May 23, 2017 9 Solid State Thyratron Replacement Motivation • Gasification • Linear Accelerators • waste gasification, • Radiotherapy for cancer treatment • coal gasification, • Radiosurgery… • Hydrogen production • Scientific… • Synthesized Fuel Production • Nuclear Fusion Reactors • Plasma Water/Air Purification Systems • Circuits • Cleaning of fracking water • Protection of sensitive • Purifying in/out water for …server farms, digital pharmaceutical manufacturing broadcast equipment, the • Purifying in/out water for food Cloud…etc. processing • Modulators • Airplane cabin conditioning • Military…Army, USN, USCG, USMC, • Industrial air pollution USAF • Lasers Systems • Commercial… Airports, Weather, Maritime • Ablation • Spectroscopy • Marx Generators • Lithography • Lightning simulation • Micromachining • Utilities HV insulation testing • Triggers • The List goes on… • Satellite Communications • UHF

ICOPS, Atlantic City, NJ May 23, 2017 10 Solid State Thyratron ABB Solid State Thyratron Replacements:

ABB: “Due to having higher reliability and lower maintenance costs, ABB’s optimized semiconductor components, mostly as complete assemblies, are increasingly being used to replace and .” However, due to having relatively low di/dt capability, ≤ 20kA/ms, they can be used in only a few thyratron applications. Remember (1) 2cm2 Solidtron demonstrates 100kA/ms!!! ICOPS, Atlantic City, NJ May 23, 2017 11 Disruptive Design Solidtron designed specifically for Thyratron replacement • low cost discrete package • Easily Paralleled or connected/gated in series • Easily cooled with Off-The-Shelf Heatsink (Max dissipation only 29W/level) • No more large presspack clamps and heatsinks !!! 1.00E+06 TO-264 Lead Frame Predicted Performance f ambient 1.00E+05 1ms ½ Pulse Width (500ns rise) f fan cooled E2v & equivalent L3 models 1.00E+04 Excelitas models HY 11 1.00E+03 HY 32/3002

CX2608/ L-4945 freq (Hz) freq 1.00E+02 CX1174/ L-4174 HY 5/53/ L-4883 CX1180/ L-4680 1.00E+01 CX1154/ L-4904

1.00E+00

Ipk (A)

ICOPS, Atlantic City, NJ May 23, 2017 12 Ultra-Fast Solid State Thyratron Replacement 40kV SSTR-1 (Twin Stack) Vs. e2v CX2282 TO-264 w/ SGTOEP_A1 TO-247 w/ SGTO4 • Initial TO-247 version demonstrated 365k pulses o 3kA, 300ns square wave • Similar 20kV and 60kV derivatives planned to complete the product offering • TO-264 version offers 36x increase in action

ICOPS, Atlantic City, NJ May 23, 2017 13 Solid State Thyratron Replacement

Anode Current Capacitor Voltage (Ch2 Max Ref only)

50nSec rise time Prototype Thyratron Peak I >4kA Replacement Switch using Rep Rate = 100PPS Ultra-Fast 1600V Solidtron 푑푖Τ • 푑푡 capability is >100kA/mSec • Yellow - 4.3kA Peak Current • Fiber Optically Triggered w/average di/dt of ~60kA/mSec • Small size - 9” Tall, 3.75” Base (Circuit Limited) diameter • Run at 100 Pulses Per Second without cooling • Voltage capability of 40kV

ICOPS, Atlantic City, NJ May 23, 2017 14 Solid State Thyratron Replacement

6.5kV High Action Solidtron 10kV (4 level) Gen1 20kV Bi-directional Switch Assembly Pulsing 200kA model shown Replaced NL-8900 Ignitrons in Magnetic Pulse Welding System (13.25” x 10.5” x 4”)

• 8 levels of 6 parallel modules (192 chips operating in concert, 96 high action Solidtron and 96 S- • 4 of these units were paralleled for 800kA • More than 10,000 operational events recorded

• Yellow - Demonstrates 200kA Ringing Waveform (169kA Peak reverse) NL-8900 Ignitrons failed after only 200 such events – customer’s original motivation to • Magenta – Voltage across a single level – ~2500V to Vf change switching technology • Cyan – 1 of 12 legs – worse case current imbalance (perfect 16.6kA)

ICOPS, Atlantic City, NJ May 23, 2017 15 Solid State Thyratron Replacement 6.5kV High Action Solidtron Pulse Switch Assembly Testing of Gen1 80kA unit at ARL • Superior Current Sharing (Cathode 1-Cathode 2) • Excellent Voltage Balance (Across 4 levels) • Synchronized and repeatable 32 Chip turn-on

80 kA Unit #016 in ARL PFN

100 90 80 70 60 Total Current 50 40 Cathode 2 30

Current (kA) Current 20 Cathode 1 10 0 -10 0 100 200 300 400 500 Time (us)

ICOPS, Atlantic City, NJ May 23, 2017 16 Solid State Thyratron Replacement

I (10kA/D) 58kA, VF 25.35V I2t = 217 kA2s

Eswitch = 131 J I2 (1e9A2/D)

dT ~ 24C 1x3 PSA with gate drive and grading P (1MW/D) R built into the low footprint cover (<100in3!) PSA Current vs. Forward Drop 70 V (100V/D) 60 PSA: VF (100V/D) R = 375mW

50 VD = 3.63V Modules: Pulse Switch Assembly (PSA): 40 R = 125mW [1] • Simple isolated current gating 30 VD = 1.21V • Coaxial current delivery for very low

PSA Current (KA) Current PSA 20 inductance 10 • 10kV DC continuous operation [1] includes ~ 26 mW parasitics 0 • Only 375mW resistance with a knee of 0 5 10 15 20 25 30 3.63V! Forward Drop () ICOPS, Atlantic City, NJ May 23, 2017 17 Summary

푑푖 • Solidtron offers unparalleled Τ푑푡 capabilities – Ultra fast capable of 200kA/ms – High action capable of 100kA/ms • 푓(푖 푡 ) 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 applications

ICOPS, Atlantic City, NJ May 23, 2017 18