ENGINEERING RESEARCH INSTITUTE UNIVERSITY OF MICHIGAN ANN ARBOR c-T-E SURFACES OF FERROELECTRIC CERAMICS Technical Report No. 53 Electronic Defense Group Department of Electrical Engineering. By: L. W. Orr Approved by: Project 2262 TASK ORDER NO. EDG-4 CONTRACT NO. DA-36-039 sc-63203 SIGNAL CORPS, DEPARTMENT OF THE ARMY DEPARTMENT OF ARMY PROJECT NO. 3-99-04-042 SIGNAL CORPS PROJECT NO. 194B October, 1955

TABLE OF CONTENTS Page ABSTRACT iii 1. PURPOSE 1 2. c-T-E SURFACES 1 3. DATA 3 4. APPLICATIONS 3 5. GENERAL REMARKS 4 6. CONCLUSIONS 4 DISTRIBUTION LIST 26 ii

ABSTRACT The available data on ferroelectric ceramics regarding tunability and temperature are presented in chart form (E-T-E Surfaces). The 21 charts are by no means a comprehensive survey of available materials because of the rapidly expanding development in this field. They represent the data currently available in a continuing materials study. iii

ENGINEERING RESEARCH INSTITUTE * UNIVERSITY OF MICHIGAN e-T-E SURFACES OF FERROELECTRIC CERAMICS 1. Purpose This report presents a series of charts which display for a number of available materials the variation in relative dielectric constant, c, as both temperature and electric field are varied. The charts are in two sections. Section 1 (Figures 1-12) deals with materials in standard production where fairly consistant results have been obtained from batch to batch. Section 2 (Figures 13-21) deals with experimental samples of new materials furnished by various laboratories. Since these materials are not in standard production, the data in each case were usually obtained from one sample, and thus no information on reproducibility is available. 2. e-T-E Surfaces Surfaces are represented in isometric projection, with e plotted vertically. The electric field axis is inclined downward to the right with the electric field increasing to the right. The temperature axis is inclined downward to the left. In most cases temperature is increasing from right to left, but this was reversed where necessary to make a clearer presentation of the surface. Tunability of the material at any temperature is obtained by inspecting the variation of e along the appropriate constant temperature line. The value of e at any point may be scaled vertically from the appropriate datum line using the. scale given on each chart.

ENGINEERING RESEARCH INSTITUTE ~ UNIVERSITY OF MICHIGAN TABLE OF CHARTS Section 1 Standard Materials FIG. NO. TITLE CURIE TEMP. PAGE OC 1 Aerovox Hi-Q 40 27 6,400 5 2 Aerovox Hi-Q 41 35 3,300 6 3 Aerovox Hi-Q 20 40 2,500 7 4 Aerovox Hi-Q 80 0? 1,900 8 5 Centralab D-31 20 4,800 9 6 Centralab D-51 40 5,300 10 7 Centralab D-71 30 7, 500 11 8 Centralab D-13 128 3,140 12 9 Glenco K-3300 (1953) 15 3,800 13 10 Glenco K-3300 (1954) 0? 4,500 14 11 Mucon VSE 63 4,700 15 12 Mucon VSR 25 15,000 16 Section 2 Experimental Materials FIG. NO. TITLE CURIE TEMP. cmax PAGE ~C 15 Aerovox BKC-1 30 2,900 17 14 Aerovox BKPC 20 3,700 18 15 Aerovox BKP1A 30 8,100 19 16 Aerovox B K50 25 3, 300 20 17 Aerovox B2K45 20 4,100 21 18 General Electric 69 ER 63 10,000 22 19 General Electric 71 ER 12 6,000 23 20 General Electric 213ER 13 6,600 24 21 General Electric 214ER 80 5,400 25

ENGINEERING RESEARCH INSTITUTE ~ UNIVERSITY OF MICHIGAN 3. Data 1 In all cases the data were taken on the BLARE automatic recording equipment. The small signal value of e was measured at 1000 cycles, and the electric field was varied cyclically between zero and (in most cases) 40 KV/cm at a slow rate (40 to 80 seconds per cycle). The temperature was held constant during cycling by immersing the specimen in a stirred oil bath. Where hysteresis effects were observed, the data were presented only for the part of the cycle when the electric field was increasing from zero to a maximum. 4. Applications The c-T-E surfaces were primarily drawn up for design work in dielectric tuning applications. However, the surfaces may be used for a wide variety of applications, ranging from variable filter design to the design of dielectric amplifiers. Above a few megacycles, the dielectric loss increases with frequency. Thus, in design problems where the loss must be considered, the c-T-E surface must be supplemented by additional data. The technique of constructing the capacitor generally has a major effect on the high frequency loss characteristics. Greatly improved results in the 20400 mc region are possible when special construction techniques2 are used. 1. "Wide-Range Tuning Methods and Techniques Applicable to Search Receivers", Quarterly Progress Report No. 13 Task Order EDG-4, University of Michigan, Engineering Research Institute, Ann A Arbor, Michigan, October 1954. 2. See for example, "Miniature Non-Linear Capacitors, " University of Michigan, Electronic Defense Group Technical Report No. 54, by H. Diamond, to be published. " ~~3 -,,

ENGINEERING RESEARCH INSTITUTE ~ UNIVERSITY OF MICHIGAN 5. General Remarks The zero field value of c is quite temperature sensitive,having a maximum value at the so-called Curie temperature of the material. The Curie temperature and maximum value of e are given in Table 1. Materials with low temperature sensitivity generally have a low dielectric constant and exhibit little variation in e with applied field. The Curie temperature generally increases as the electric field is applied Thus, if the ceramic is operated at the zero field Curie temperature, it will have a positive temperature coefficient of dielectric constant when an electric field is applied. For applications where close tolerances on the capacitance are required, it is usually necessary to apply temperature control devices to satisfy these requirements. 6. Conclusions Although only a limited and not necessarily representative amount of data areavailable, it is felt that publication at this time will assist the increasing number of workers now employed in applications of these materials.

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:60~.0o oO,o00' ONo o < 60 I~~ ~ 0 q0 tl~~~~~~~~~~~~~6o s~~~~ Cc t 9 A9or nv W/-"A 4-,<O"~). ~.'. ~o'~~ ~~4),3. FIG. 2 6.-T- E SURFACE C O A rbDNl\~ INV~ f" WI-(~,

zoo o?40o~ 00~ 0O 160 000 ~ — ol,.O< O<C cp 600~~~~~~~~~~~~~~~~~~~~~~~~~~,' 400 ~~';',,~.~?q.t~, FIG. 3 6-T-E SURFACE AEROVOX HI-Q20

8 08 O-IH XOAOJ3 V 33Jv.iunS 3-1-9 vb'911 6,,, 0 2262 D-4-123RRCSZ-S5-I5

6 I~-Q 8V1VUI..N30 330v._lns 3-L-a 9'91I oo 00 /3/ ~~~'b" >" 01 09 boaL Cb 0,, 9~~~~~~~~~~~~~~~~~~~~~.0001 o oo.000~,ooo',~ O0 00 2262 D-"- 122 OM 9-28-55

4400 1600 CENTRALAB D-51 10 66~~~ /f: ~ ~ -TE URAC

1500 6000 450Q0 000, t500 FIG. 7 6-T-E SURFACE CENTRALAB D-71 11

~ CENTRALAB BATCH NO. H51-13,#151-958 ~ EAC=.OI KV.CM-'(RMS) AT I KC ~ CYCLING FIELD ONE POLARITY ~ CYCLING FIELD RATE = 70 KV.CM.' MIN)' ~ DATA PLOTTED ONLY FOR EDC INCREASING oo'0 00:30 2100 ~400. ~I00' ~oO' I600 C,o, ~~~~~ ~~~~j~~~ < 60, 5'"~~~~~~~~~~~~~~~~~~~~~~~~A: 00 FIG. 8 T600F i~T FOR CENTRALAB D-I3 OL,0~~~~~~~/~-,8~~~~~~' "o ",,~~c *a 4~~~0;IG. ~p ~CTE UFC ~~FRCENRAA D-1 ~~~t ~~ ~;s~~12

(2961) 0022 ON3-19'OV-dfns 3-1- 3 6'91 os~~~~~~.o 4, Q~~~~~~~~~~~~~~~~~~~~~~~~~I,0 ~ ~ ~~ r' oO ~~' 09 toog X 001t N ~~~~~~~~~~~~~~~~3 N~~~~~~~~~~ N~~~~~~~~~~ N e ~ I I ~ 9` s~ N~~~~~~~~~~ N~~~~~~~~~~~ N~~~~~~~~~~~~ 00zv ~~~~~~~~\1 \~~~~~~~~~~e \~~~~~~~~~~~~gZ \~~~~~~~~~~~~~~~~~~~~~~~~26 -414 RC-0

00GLENCO 3300 (1954) 01400 O~~~~LENO:30(94 "C~~p CLO 1

0 60o E3 0001 0.: 000 FIG. II 6-T- E SURFACE FOR MUCON VSE,~~~~~~~~~~~~~~~~~o tn ~, / /~ a~~~~~~~~~~~~~~ -o~..' 5/<~~'~0 CL~.b ~~~~~~~~~~~~~o.~~'*'' ~2~ I ~ ~ ~~ IFIG. I 6-T- E SU~~~~~~~RFAC ~~~PO MUON S

DIELECTRIC CONSTANT` In CALIBRATION ACCURACY =-' 25% 6 ~~~~~~~~~~~~~~~~~~~~~~\\ 1 00' ~~~~~~\\ c 000O 600' I \ ~~~~~~~'o~-~~~~~~~~~~~~~~~~~~~~~~,,\~ ~ Q 16000' ". 000' <~~~~~~~~~~~~~~~~~~~~~< <01,~~~~~~~~~~~~~~~~~~~~~~~~~~~~~c %SI /tj % FIG. 12,-T- E SURFACE C'nD RAI ltt-AKI %/C

3000 z400 1800 600 FIG. 13 C-T-E SURFACE AEROVOX BKC-I 17

99-8z-6 we 9?1-tlo-a 39zz'400 350 400 5, ~0o~1,~~ooO g5o~ (150~ c2 c_ i000 500 ~ ~ ~ ~ ~ ~ /..~ 5oo I 400~~~~~~~~~~~~~~~~~~~~5 0 " Co -o FIG. 14 6-T-E SURFACE AEROVOX BK-PC 18

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oz 0~- t8 X0o0t83/ 3N3ojnS 3-1-9 91!SDz 9I'9I-q r~,or 0091 oCO

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1500 9000 4500 3000' 1500 90 LD"~'fo FIG. 18 C-T-E SURFACE GENERAL ELECTRIC 69ER 22

83-I. 318103313 1VI'3N39 33V-l ns 3-1-3 61'91J cb O> ocs -0 00,01, 00o9 0J 0009

00o 6000 eoo~ 3000 ~>2 1000':Z3 /4/ FIG. 20 P-T-E SURFACE

gz 3it71I 312.L3313 9V8t3N39 WCO0 3ovjwnS 3-.L-3 Iz'O1l 6'~~~~~~~~~~~~6 _c~_ _L00 o i~~~~~~~~~~~~~~~~~~~~~~~~~~~~~/ ~ t 0~~~~~~~~~~~~~~~~~~~091 I09~~~~~~~~~~~~~~9 ~~~~~~~~~~~~~~~~~~oO~ ~~~~~~/to 009g ooov 2262D G4 0S6C9-26-5

DISTRIBUTION LIST 1 Copy Director, Electronic Research Laboratory Stanford University Stanford, California Attn: Dean Fred Terman 1 Copy Commanding General Army Electronic Proving Ground Fort Huachuca, Arizona Attn: Director, Electronic Warfare Department 1 Copy Chief, Research and Development Division Office of the Chief Signal Officer Department of the Army Washington 25, D. C. Attn: SIGEB 1 Copy Chief, Plans and Operations Division Office of the Chief Signal Officer Washington 25, D. C. Attn: SIGEW 1 Copy Countermeasures Laboratory Gilfillan Brothers, Inc. 1815 Venice Blvd. Los Angeles 6, California 1 Copy Commanding Officer White Sands Signal Corps Agency White Sands Proving Ground Las Cruces, New Mexico Attn: SIGWS-CM 1 Copy Commanding Officer Signal Corps Electronics Research Unit 9560th TSU Mountain View, California 60 Copies Transportation Officer, SCEL Evans Signal Laboratory Building No. 42, Belmar, New Jersey FOR - SCEL Accountable Officer Inspect at Destination File No. 22824-PH-54-91(1701) 1 Copy J. A. Boyd Engineering Research Institute University of Michigan Ann Arbor, Michigan 26

1 Copy H. W. Welch, Jr. Engineering Research Institute University of Michigan Ann Arbor, Michigan 1 Copy Document Room Willow Run Research Center University of Michigan Willow Run, Michigan 11 Copies Electronic Defense Group Project File University of Michigan Ann- Arbor, Michigan 1 Copy Engineering Research Institute Project File University of Michigan Ann Arbor, Michigan 27