Dual Doping Source DDS - Dopant Cells -

Cluster sources increase the capacity of UHV systems
Customized designs with all kind of effusion cells
Compact and intelligent cell design
Various crucibles available
Solutions with integrated cooling shrouds and shutters Datasheet

Introduction

Cluster sources provide a convenient method for adding MBE capabilities into your UHV chamber or MBE system, either as dopant or thin-film deposition source. Because of the large variety of different UHV systems each cluster is individually designed for our customers’ systems.

We build cluster source flanges based on our standard cells. A large variety of clusters with two or more different cells mounted even on a small flange is offered.

Specially designed thermal shielding featuring water-cooled shields between the individual cells reduces thermal interaction. Cross contamination is minimized by the use of individual, non-overlapping shutters.

A brief selection of different cluster sources is presented in the following. Some thinkable applications for our cluster sources are shown as examples. Please contact us for more information about custom-made solutions.

A Dual Doping Source used for Si and Be doping on a single DN63 CF (O.D. 4.5") port is presented in the picture on the right.

The use of dual doping sources increases the capacity of MBE systems, e.g. GEN II, by using only a single port for both Be and Si doping. After melting the source material in an upwards position the cells can be used in downward oriented ports. For easier melting of the source material we deliver a special set of PBN and Ta shielding parts.

The double cluster source with 2 x 5.6 cm³ PBN crucibles shown on the right is mounted on a DN63 CF (O.D. 4.5’’) flange. It is equipped with a special water cooling between the two small effusion cells and with a rotary motion shutter for each cell.

This design is favorable in horizontal mounting position where there is the risk of material falling down from the crucible.

The combination of a mini high temperature effusion cell HTEZ and a standard effusion cell WEZ, mounted on a DN63 CF (O.D. 4.5") flange is shown in the picture.

The HTEZ includes an 1.5 cm³ Al₂O ₃crucible, while the WEZ is equipped with a 10 cm³ PBN crucible. The integrated water cooling shroud prevents heating of the chamber as well as thermal interaction of the individual cells. The two separate shutters allow independent operation with minimized cross contamination.

Two single standard effusion cells WEZ, with a 10 cm³ PBN crucible in each cell, are mounted in an angled position to allow the use of a horizontal port below the substrate. Each cell is equipped with an individual linear shutter.

Application

The use of the Dual Doping Sources increase the capacity of your MBE System, e.g. GEN II, by using only a single port for both Be and Si doping. After melting the source material in an upwards position the cells can be used in downward ports. For easier melting of the source material we deliver a special set of PBN and Ta shilding parts.

Technical Data

Mounting flange	DN63 (O.D. 4.5") other sizes on request
Dimensions in vacuum	Length : 216(-400) mm; Diameter : 55 mm for DDS 63-2xC5-S Length : 266 -326 mm; Diameter : 62 mm for DDS 63-2xC5-S (V80) (larger shutters) Length : 266(-400) mm; Diameter : 36 mm for DDS 63-2x2-S
Ta wire Filament	max. power 250W/10A for DDS 63-2xC5-S max. power 160W/7A for DDS 63-2x2-S
Temperature sensor	W5%Re/W26%Re (Type C)
Bakeout temperature	250°C
Operating temperature	200°C - 1400°C (recommended 700-1350°C)
Outgassing temperature	1500°C (1600°C for short times)
Crucibles	PBN 2ccm and PBN 5ccm
Cooling	water cooling between the cells
Shutter	integrated rotary shutter ( S )

Crucibles

Crucible sizes from 1.5 to 10 cm³ are usually possible in the very compact cluster designs. Other dimensions and different shapes (cylindrical, conical) are available on request. By default the “dual” doping sources are designed as two-cell-clusters. However we are to supply customized solutions with three or more cells on one mounting flange tailored to the customer’s need. The standard crucible material is PBN, but other crucible materials are also available.

Dimensions

Schematic drawing DCS — Schematic drawing of the Dual Doping Source DDS (drawing shows DDS 63 2xC5-27-2S with integrated shutter)

Specific data

For general information on CF mounting flanges see Flange and Gasketdimensions .

Product	CF flange	Nominal capacity	Lip diameter	Shutter*	Filament type	Thermocouple	Crucible material**	UHV dimensions*** [mm]	max. electrical [W]/[A]	Power supply product code	Crucible product code
		[cm³]	[mm]		Type	Type		[mm] / [mm]	[W] / [A]	Product code	Product code
DDS	63 -	2x2 -	16 -	2S -	SF¹ -	C³ -	P -	LxxxD36	240 / 10	2x PS 30-10-C	PBN 2-16
DDS	63 -	2x5 -	27 -	2S -	SF¹ -	C³ -	P -	LxxxD55	250 / 10	2x PS 30-10-C	PBN C5-27
DDS	63 -	2x8 -	27 -	2S -	SF¹ -	C³ -	P -	LxxxD55	250 / 10	2x PS 30-10-C	PBN C8-27
DDS	63 -	2x5 -	27 -	2S -	SF¹ -	C³ -	P -	LxxxD62	250 / 10	2x PS 30-10-C	PBN C5-27

* rotary shutter possible on same flange ¹ alternatively CL ** PBN standard, other materials on request ² alternatively CL, HL or DF *** specify UHV length L with order ³ alternatively type K

Product code:
e.g. DCS 63-2x5-27-S-SF-C-P-L216D55 is a dual doping source on a DN63 flange, with two 5cm³ PBN crucibles (lip diameter 27mm), integrated rotary shutter, standard filament heaters, type C thermocouple, in-vacuum length 216mm and diameter 55mm.