Layer transfer of semiconductors and complex oxides by helium and,or hydrogen implantation and wafer bonding [Elektronische Ressource] / von Ionut Radu

Sujets

• Physik

Informations

• Publié par: martin-luther-universitat_halle-wittenberg
• Publié le: 01 janvier 2003
• Nombre de lectures: 16
• Langue: English
• Poids de l'ouvrage: 3 Mo

Extrait

Layer transfer of semiconductors and complex oxides
by helium and/or hydrogen implantation
and wafer bonding
Dissertation
zur Erlangung des akademischen Grades
_Doctor rerum naturalium (Dr. rer. nat.)
vorgelegt der
Mathematisch-Naturwissenschaftlich-Technischen Fakult˜at
(mathematisch-naturwissenschaftlicher Bereich)
der Martin-Luther-Universit˜at Halle-Wittenberg
von Herrn Ionut Radu
geb.: 15.05.1976 in: Campina
Gutachter:
1. Prof. Dr. Heinrich Graener (Martin-Luther-Universit˜at Halle-Wittenberg)
2. Prof. Dr. Ulrich G˜osele(Max-Planck-Institut fur˜ Mikrostrukturphysik)
3. Prof. Dr. Siegfried Mantl (Forschungszentrum Julic˜ h, ISG1-IT)
Halle (Saale), am 4 November 2003
urn:nbn:de:gbv:3-000005814
[http://nbn-resolving.de/urn/resolver.pl?urn=nbn%3Ade%3Agbv%3A3-000005814]Contents
1 Introduction 8
2 Layer transfer by ion implantation and wafer bonding 11
2.1 General features of the layer transfer process . . . . . . . . . . . . . . . . . . . . 11
2.2 Ion implantation induced layer transfer . . . . . . . . . . . . . . . . . . . . . . . 13
2.2.1 Hydrogen in crystalline semiconductors . . . . . . . . . . . . . . . . . . . 14
2.2.2 Helium in . . . . . . . . . . . . . . . . . . . . 15
2.3 Basics of blistering and splitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.3.1 Onset of blistering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.3.2 Splitting kinetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.4 X + H co-implantation technique . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.4.1 B + H co-implantation approach . . . . . . . . . . . . . . . . . . . . . . 20
2.4.2 He + Htationh . . . . . . . . . . . . . . . . . . . . . . 22
2.4.3 Two-step H implantation approach . . . . . . . . . . . . . . . . . . . . . 22
2.5 Wafer direct bonding and layer transfer . . . . . . . . . . . . . . . . . . . . . . . 22
2.5.1 Surface treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.5.2 Room temperature bonding . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.5.3 Bonding energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.6 Objectives of this work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3 Experimental 33
3.1 Ion implantation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.2 Beam heating efiect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.3 Experimental procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3.4 Wafer bonding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
3.4.1 GaAs on Si . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
3.4.2 Bonding of complex oxides . . . . . . . . . . . . . . . . . . . . . . . . . . 46
4 Results and discussion 47
4.1 Blistering and exfoliation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.1.1 Hydrogen implantation into GaAs . . . . . . . . . . . . . . . . . . . . . . 47
4.1.2 Helium implantation into GaAs . . . . . . . . . . . . . . . . . . . . . . . 51CONTENTS 2
4.1.3 Helium + hydrogen co-implantation into GaAs . . . . . . . . . . . . . . . 57
4.2 Blistering and exfoliation of complex oxides . . . . . . . . . . . . . . . . . . . . 60
4.2.1 SrTiO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 603
4.2.2 LaAlO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 633
4.2.3 LiNbO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 663
4.2.4 PLZT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
4.3 Layer Splitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
4.3.1 GaAs layers on Si substrates . . . . . . . . . . . . . . . . . . . . . . . . . 73
4.3.2 Transfer of complex oxide layers onto difierent substrates . . . . . . . . . 75
4.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
5 Blistering and splitting mechanisms 77
5.1 Development of blistering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
5.2 Blistering versus exfoliation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
5.3 Dynamics of layer splitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6 Conclusions and outlook 89
Bibliography 92List of Figures
2.1 Schematics of layer transfer by ion implantation and wafer bonding approach. . 12
2.2 Schematic description of the blistering and splitting processes. . . . . . . . . . . 17
2.3 Cross section TEM image of H-platelets in silicon [99]. . . . . . . . . . . . . . . 18
2.4 Logarithm of inverse time required for on-set of blistering or layer transfer (split-
16 + 2ting)forH-implanted(5.5x10 H /cm at69keV)siliconasafunctionofinverse
temperature [100]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.5 BlisteringtimeasafunctionofinverseabsolutetemperatureforB+Hco-implanted
–(a), B+H co-implanted and pre-annealed at 250 C for 10 minutes (b) or 50 min-
+utes (c) and H-implanted only (d) Si wafers. Hydrogen (H ) was implanted at2
16 ¡2130 keV with a dose of 5x10 cm while for co-implantation experiments boron
+ 14 ¡2(B ) was implanted at 180 keV with a dose of 5x10 cm prior to hydrogen
implantation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.6 Schematic drawing of a gap caused by atness non-uniformities [119]: (a) R >
2d; (b) R < 2d. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.7 Schematics of crack-opening method for investigating the bonding energy [128]. . 26
2.8 Comparison of surface energies of bonded hydrophilic and hydrophobic Si/Si
pairs as a function of annealing temperature [116]. . . . . . . . . . . . . . . . . . 27
2.9 Schematics of blistered bonding interface. Here d refers to the thickness of the
bonded wafers and t to the thickness of the delaminated layer approximately
corresponding to the hydrogen implantation depth. . . . . . . . . . . . . . . . . 28
2.10 Calculated critical surface energy ? required for layer splitting for Si/Si: HB -c
hydrophobic bonding and HL - hydrophilic bonding [106]. The crossing points
for hydrophilic and hydrophobic bonding are indicated. . . . . . . . . . . . . . . 28
3.1 Schematic drawing of an ion implanter. . . . . . . . . . . . . . . . . . . . . . . . 34
3.2 Schematics of the relative energy loss due to electronic (S ) and nuclear (S )e n
stopping processes, as a function of incident ion energy [79]. . . . . . . . . . . . 35
+3.3 DepthdistributionandprojectedrangeofH -implantationat160keVcalculated2
by using the TRIM code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.4 Schematic description of the multi-step hydrogen implantations performed in
Novosibirsk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.5 Schematic drawing of the implantation process. . . . . . . . . . . . . . . . . . . 39LIST OF FIGURES 4
23.6 Beam heating curves for difierent beam current densities: a) P = 3 W/cmbeam
without thermal contact between the wafer and the wafer holder, b) P =beam
2 220 W/cm without thermal contact, and c) P = 20 W/cm with thermalbeam
contact between the wafer and the wafer holder deflned by a heat conduction
coe–cient of 0.5 W/K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
3.7 Specimen preparation of investigated materials for XTEM investigation. . . . . . 43
3.8 Schematic o wchart of the GaAs/Si wafer bonding via SOG layer process. . . . 44
–3.9 Infrared re ection spectrum of a SOG layer annealed at 150 C for 5 min. . . . . 45
3.10 Typical IR image (a) and acoustic microscopy image (b) of GaAs-Si bonding
interface after bonding via a SOG intermediate layer. . . . . . . . . . . . . . . . 45
3.11 IR images of as-bonded 4-inch LiNbO /LiNbO (a) and 30 mm diameter3 3
SrTiO /SrTiO (b) wafer pairs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463 3
4.1 Surface blisters in as-implanted GaAs observed by optical microscopy (a) and
+ 16 ¡2AFM (b). H implantation at 130 keV with 3.5x10 cm was performed at2
–100 C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
16 ¡24.2 Cross section TEM image of hydrogen (130 keV, 3.5x10 cm ) as-implanted
–(100) GaAs wafer at 100 C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
16 ¡24.3 Cross section TEM image of helium (105 keV, 5x10 cm ) as-implanted (100)
GaAs at RT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
–4.4 Exfoliation after 1 hour annealing at 300 C of He implanted (100)-GaAs at
RT: a) exfoliated thin layer piece and b) remaining part after exfoliation in the
16 ¡2surroundings (implantation energy 105 keV, dose 5x10 cm ). . . . . . . . . . 52
4.5 Activation energies of exfoliation for He-implanted (100)-GaAs. Implantation of
+ 16 ¡2He (5x10 cm at 105 keV) was performed at RT. . . . . . . . . . . . . . . . 53
4.6 Cross section TEM image of as-implanted (111)-oriented GaAs. Implantation of
+ 16 ¡2He (5x10 cm at 105 keV) was performed at RT. . . . . . . . . . . . . . . . 55
4.7 Activation energies of exfoliation for He-implanted (111)-GaAs. Implantation of
+ 16 ¡2He (5x10 cm at 105 keV) was performed at RT. . . . . . . . .