ULTRA and ULTRA-AS Ion Implanted Silicon Charged Particle Radiation Detectors

ULTRA ion-implanted-silicon detectors for alpha and beta spectroscopy are the most advanced charged-particle detectors ever produced. They possess the reliability that has made ORTEC the sole supplier to NASA of silicon detectors for space applications.

Both the entrance and the back contact are ion implanted. The entrance contact is an extremely thin (∼500 Å) boron implantation. The distance between the silicon surface and the top of the mounting can is <1 mm providing maximum geometric efficiency. The front contact can be easily cleaned with a solvent-moistened cotton swab.

ULTRA detectors have gold-plated mounting cans. The superior electrical conductivity of gold, which can never oxidize, makes it the choice versus stainless steel or aluminum. An advanced surface passivation that covers the critical silicon dioxide layer guarantees absolute device stability.

The extremely low leakage current permits specifying the energy resolution at 1-µs amplifier shaping time constant.

Low-background ULTRA-AS detectors are made with special low-background materials and have an optimized depletion thickness to minimize background counts from cosmic rays. All ORTEC Alpha Spectrometers (Alpha Aria, Alpha Duo, and Alpha Ensemble) can be equipped with either ULTRA-AS detectors or R-Series, Ruggedized Surface Barrier Detectors. All these spectrometers, when equipped with a 450 mm² detector, have a warranted background performance of ≤24 counts per day, over the 3- to 8-MeV energy range.

The dimensions of the ULTRA and ULTRA-AS detector mounting cans being identical to those of the corresponding size A or R Series detectors ensure that ULTRA detectors will fit perfectly in any application where A or R Series detectors are being used now.

*Extensive care regarding detector and chamber cleanliness can result in background count levels as low as 0.05 counts/hr/cm² of active area, corresponding to 6 counts/24 hours, for a 450 mm² active area.

**ULTRA Series detectors require positive bias voltage. R Series detectors require negative polarity bias.

B  Microdot connector on the rear of the can.

C  BNC connector on the rear of the can.

T  Microdot on the side of the can. Only one side of the can has an opening. Available up to 600 mm² active area.

Dimensions given in millimeters.

Detector Size (mm2)	W (Nominal)	Type B Rear Microdot			Type C Rear BNC			Type "BLIND" T Side Microdot
		X	Y	Z	X	Y	Z	X	Y	Z
025	5.6	16.7	12.3	7.1	16.7	12.3	15.9	19.4	7.9	9.9
050	8.0	16.7	12.3	7.1	16.7	12.3	15.9	19.4	7.9	9.9
100	11.3	23.6	12.3	7.1	23.6	12.3	15.9	26.1	7.9	9.9
150	13.8	23.6	12.3	7.1	23.6	12.3	15.9	26.1	7.9	9.9
300	19.5	28.6	12.3	7.1	28.6	12.3	15.9	31.6	7.9	9.9
450	23.9	32.0	12.3	7.1	32.0	12.3	15.9	34.8	7.9	9.9
490	25.0	33.4	12.3	7.1	33.4	12.3	15.9
600	27.6	36.1	12.3	7.1	36.1	12.3	15.9	38.4	7.9	9.9
900	33.9	45.2	12.3	7.1	45.2	12.3	15.9
1200	40.0	48.8	12.3	7.1	48.8	12.3	15.9
2000	51.0	65.5	12.3	7.1	65.5	12.3	15.9
3000	62.0	76.2	12.3	7.1	76.2	12.3	15.9
Tolerance	±0.5	±0.3	±0.3	±0.3	±0.3	±0.3	±0.3	±0.3	±0.3	±0.3

Specify B, C, or "Blind" T** Mount. To Order: Add the appropriate letter prefix for the mounting desired. Example: BU-016-300-100 or TU-016-300-100.

* First three digits of Model No. indicate total system resolution FWHM for ²⁴¹Am, 5.486-MeV alphas, using standard ORTEC electronics and 1-µs shaping time constants.

** “Blind” T Mount available up to 600-mm² ULTRAs.

NOTE: Alpha Suite Compatible Detectors: ULTRA-AS and Low-Background R Series detectors in B-mount are guaranteed compatible with the Alpha Suite products (DUO, MEGA, ARIA, ENSEMBLE).  All other detectors require an approved special for compatibility and warranted specifications.

Active Area (mm2)	Guaranteed Maximum Resolution* (keV FWHM)		Minimum Depletion Depth 100 µm
	α	β	Model No.
25	12 14	6 8	U-012-025-100 U-014-025-100
50	12 14	6 8	U-012-050-100 U-014-050-100
100	13 15	7 9	U-013-100-100 U-015-100-100
150	14 16	9 10	U-014-150-100 U-016-150-100
300	16 19	11 14	U-016-300-100 U-019-300-100
450	17 21	12 16	U-017-450-100 U-021-450-100
600	22 24	17 19	U-022-600-100 U-024-600-100
900	27 33	22 28	U-027-600-100 U-033-900-100
1200	35 42	30 37	U-035-1200-100 U-042-1200-100
2000	50 58	45 53	U-050-2000-100 U-058-2000-100
3000	60 70	55 65	U-060-3000-100 U-070-3000-100

Active Area (mm2)	Guaranteed Maximum Resolution* (keV FWHM)		Minimum Depletion Depth 300 µm
	α	β	Model No.
25	11 13	5 7	U-011-025-300 U-013-025-300
50	11 13	5 7	U-011-050-300 U-013-050-300
100	12 14	6 8	U-012-100-300 U-014-100-300
150	13 15	8 9	U-013-150-300 U-015-150-300
300	15 18	10 13	U-015-300-300 U-018-300-300
450	16 20	11 15	U-016-450-300 U-020-450-300
600	21 23	16 18	U-021-600-300 U-023-600-300
900	25 30	20 25	U-025-900-300 U-030-900-300
1200	30 37	25 32	U-030-1200-300 U-037-1200-300
2000	40 48	35 43	U-040-2000-300 U-048-2000-300
3000	55 65	50 60	U-055-3000-300 U-065-3000-300

Active Area (mm2)	Guaranteed Maximum Resolution* (keV FWHM)		Minimum Depletion Depth 500 µm
	α	β	Model No.
25	11 12	5 6	U-011-025-500 U-012-025-500
50	11 13	5 7	U-011-050-500 U-013-050-500
100	12 14	6 8	U-012-100-500 U-014-100-500
150	12 14	7 9	U-012-150-500 U-014-150-500
300	14 17	9 12	U-014-300-500 U-017-300-500
450	15 19	10 14	U-015-450-500 U-019-450-500
600	20 22	15 17	U-020-600-500 U-022-600-500
900	23 28	18 23	U-023-900-500 U-028-900-500
1200	28 38	23 30	U-028-1200-500 U-035-1200-500
2000	35 43	30 38	U-035-2000-500 U-043-2000-500
3000	50 60	45 55	U-050-3000-500 U-060-3000-500

Specify B, C, or "Blind" T** Mount. To Order: Add the appropriate letter prefix for the mounting desired. Example: BU-034-1200-AS or TU-019-300-AS.**

* First three digits of Model No. indicate total system resolution FWHM for ²⁴¹Am, 5.486-MeV alphas, using standard ORTEC electronics and 1-µs shaping time constants.

** “Blind” T Mount available up to 600-mm² ULTRA-AS.

~100 µm active depth to minimize cosmic background.

NOTE: Alpha Suite Compatible Detectors: ULTRA-AS and Low-Background R Series detectors in B-mount are guaranteed compatible with the Alpha Suite products (DUO, MEGA, ARIA, ENSEMBLE).  All other detectors require an approved special for compatibility and warranted specifications.

Active Area (mm2)	Alpha Resolution* (keV FWHM @ 5.486 MeV)	Model No.
300	19	U-019-300-AS
450	20	U-020-450-AS
490	20	U-020-490-AS
600	24	U-024-600-AS
900	29	U-029-900-AS
1200	37	U-037-1200-AS
2000	53	U-053-2000-AS
3000	64	U-064-3000-AS

ULTRA-AS to be installed and system tested with an Alpha Suite Spectrometer.

Supplied in B Mount.

* First three digits of Model No. indicate total system resolution FWHM for ²⁴¹Am, 5.486-MeV alphas, using standard ORTEC electronics and 1-µs shaping time constants.

~100 µm active depth to minimize cosmic background.

NOTE: Alpha Suite Compatible Detectors: ULTRA-AS and Low-Background R Series detectors in B-mount are guaranteed compatible with the Alpha Suite products (DUO, MEGA, ARIA, ENSEMBLE).  All other detectors require an approved special for compatibility and warranted specifications.

Active Area (mm2)	Alpha Resolution* (keV FWHM @ 5.486 MeV)	Model No.
300	19	ENS-U300
450	20	ENS-U450
490	20	ENS-U490
600	24	ENS-U600
900	29	ENS-U900
1200	37	ENS-U1200
2000	53	ENS-U2000
3000	64	ENS-U3000