EP1320873A1

EP1320873A1 - Device and method for the planar connection of two wafers for a thin-grinding and separation process of a wafer product

Info

Publication number: EP1320873A1
Application number: EP01982138A
Authority: EP
Inventors: Franz Hecht; Werner Kröninger; Melanie Lutzke
Original assignee: Infineon Technologies AG
Current assignee: Infineon Technologies AG
Priority date: 2000-09-29
Filing date: 2001-09-26
Publication date: 2003-06-25
Also published as: DE10048881A1; US6972069B2; US20030173017A1; WO2002027764A1; US20060032587A1

Abstract

The device for the planar connection of two wafers (1, 2) for a thin-grinding and separation process of a wafer product (1) has a vacuum chamber (3), a chuck (4) for receiving a wafer support (2), a heating device (6) for heating the chuck (4) and a vacuum chamber cover (18) comprising a device (19) for maintaining a vacuum, from which a wafer product (1) can be suspended above the wafer support (2). To make the connection, after the vacuum chamber has been evacuated, the active surface of the wafer product (1) is dropped onto a double-sided adhesive film placed on the wafer support and is pressed onto said film by the increasing pressure during aeration.

Description

description

Device and method for planning the connection of two wafers for thin grinding and the cutting of a product wafer

The invention relates to a device and a method for the planar connection of two wafers for thin grinding and a separation of a product wafer according to the subject matter of the independent claims.

A method for thin grinding of semiconductor chips is known from US Pat. No. 6,045,073, in which the chips are first electrically connected on their active surface to a contact surface of a system carrier via contact bumps and are potted with a silicone compound in the edge region. The back of the chips is then freed of silicone residues and the back of the chips is subjected to a plasma etching process in order to thinly etch the chip to a few μm.

This method has the disadvantage that thin etching cannot be used for many chips simultaneously on a large-area wafer, but is only limited to relatively small areas of a single chip. The limitation of the previous solutions to the thin etching of individual chips is essentially due to the fact that a planar connection of a large-area carrier to a large-area wafer is problematic. Even with small deviations in the parallelism of the carrier and the wafer, there are considerable differences in thickness from one edge region of the wafer to the other edge region, so that a uniform thin etching of the entire wafer to a few μm cannot be achieved with the previously known method, especially since commercially available wafers have a diameter of 150 to 300 mm.

The object of the invention is therefore to create a device and a method for the planar connection of two wafers for thin grinding and the cutting of a product wafer,

P. H- Ω CQ r 2! > d ET CQ σ Di t) Hi D. <^> * - rt ii Φ NM CQ ϊ Ω Di <<φ i li Ω er

PQ Φ PJ 0 Φ PJ Φ PJ Ω H- Φ l I- ¹ Φ PJ C 0 H- C H- ^ H μ- Φ Φ Φ φ μ- Φ μ- ET Φ

Pf et CQ H- Hi H ET φ »i 0 PJ = 3 f Hi (- ^■ CQ P EJ Φ Hl Ω CQ μ- ¹ 3 li ii P ii PJ μ- μ- rr CQ tr D. o. Φ CQ rt Φ CQ i Ω c T H- CQ li μ- μ- ET • 0 0 = tr • d

Ω (- ^■ PJ CQ H Φ Φ Ei Φ <d E ^ <c φ φ PJ CQ ¹ - φ P li CQ <0: μ- fö CQ α. Sj α. IT tu tΛ Φ CQ H- Ei t J φ PJ 3 H- d Φ Ω ii D. u P = rt Φ P Φ P = 0 φ

PJ PJ H CQ H- rt Φ tu <- et Ei ET N 0 Hl H- Ef Cϊ C Ω l er Pi ii Ω D. N 3

Hl tΛ Φ Φ? R rt J H- i C 0 c: .V c J Φ D. P rt Sl P CQ f ^ tr P φ Hl ^ Φ P

Φ Ω 3 Φ H- P CQ 3 ld ≤ 0 c H Ei Φ D. MC PJ CQ Φ μ- μ- PPJC ^Q ii φ

1-i α ⁴ H- CQ Hi * e) ii 3 tu El 3 rt ii Φ H- Ei Hl CQ Di • ei P CQ tr Φ rt Q π> rt i 3? ei N H- - Hl CQ w Φ Di i Ω CQ φ CQ Φ Di i Φ N ei μ- μ- ii T li Φ H- φ Φ 0 ζ Ω PJ Φ li tu <! Φ Φ T> i Φ P 3 Φ P s: φ rt P Φ P for: ei Φ li H- Φ P. H- t 3 li C 3 0 CD H- H rt Hi 3 Φ Di P φ P Φ P μ -

P <! ti r-> Φ 13 tr c CQ et 3 Φ 3 i E ⁾ li C & J tU: α t μ- μ- Φ P Ω

IQ 0 M φ er Φ Φ Ω C Φ C Ei Φ ei Ω Φ PJ = Ei ei & P Pf φ u ≥! φ PJ Pi μ- Φ T

CD P? er H- Φ 3 i rt E ^ Ei i Ei rt H- ET> i IQ CQ Hi rt 3 CQ P Φ ii P P = P P rt

3 PJ Φ »D. Φ CQ Pi Di Ω C Φ D- Φ C Φ PJ φ Hi μ- CQ P Φ - •

P. Φ 0 P «Di Ω φ 2. Ei PJ c- φ T Ω t ii N PJ μ- li -> rt CQ 21 φ P ii Φ μ- pt 0 Φ tr Ei PJ E ^ Ei ι-3 er Ω rt H c CQ Ei Hl PJ Φ> li P PJ er NP ei

(D P Φ p P P Hi Φ PJ CQ i φ W d CQ Φ ei PJ PJ P P Φ P Hi Φ P Φ 3 Hl

0 Φ H- rt Ω * τ- Φ H- rt Φ tU: H φ Ei er PJ «Ei tΛ CQ er Hi et CQ φ P pj: P 0

CQ M et J j; v 0 li Ei 0 CQ CQ c Φ Hi> u D- rt T3 Φ CQ Φ Φ li et rt μ- ii

Φ H- 3 0 Φ Du ii Φ D. Ei Ei Φ c 3 Φ ii <PJ P P N CQ Di

0 <3 P H- PJ H- c 3 Φ D. ei φ PJ Hl D. Di ti Hl 3 ii Di P = 0 er • 3 er Φ • d P Φ li J pp H- P Φ Ei Ei Ei Ei 3 Ei £ = Φ Ei Φ μ- Ω li φ 0 0 = Φ P li li

0.? R s D. u Φ IQ Pi <! Φ S! IQ H Φ Ei PJ u H Φ φ P N D. CQ μ- Φ Di

0 P Φ rt φ PJ 0 <rt PJ Φ H- Ei ET <J μ- Φ P 3 Φ Ω J μ-

Φ P H- s H- 0 c: i Ei 0 Hl li 0 Φ ES CQ CQ 3 0 Ei <P CQ μ- li μ- Di ö t P Ω r 3 rt 0 0 li Hi Φ H H- φ tU: i H- Φ Ω Φ Φ h- ¹ φ 0 • rt rt Ω Φ J Φ P tr tr Φ JP Di H D- et CQ ü CQ D. tJ Ei ET er H φ tu ET 3 P t

H- tu H P 3 D- Φ (ϋ rt Φ Ei Φ H- H Φ 3 <»i H i P - Di tu μ-

CQ H> Φ PJ P CQ Φ Φ>? ei H- H- ei Φ Ei <Ω PJ H- Φ PJ μ- Φ P. sS 3 er Φ P CQ rr rt μ 3 rt rt 3 h- ¹ 0 rt PJ Ω E! Ei Pf Ω> 3 Φ μ- μ- Φ P Hi et

Φ H * Di PJ = Φ Φ <2. * ϋ f rt E ^ φ * »C E C H ii rt ti -

<<rt P P d r PJ Φ J H- H C • »rt CQ rt CQ Ω Φ Di K φ

P 0 0 JU:? D. Ei Φ Λ ^* D. H- Hi ω 0 C Φ Φ 3 C Hl Φ tr tr JP D.

0 HH rt Φ H- ι-3 rt Ei C PJ ES φ rr Di 3 Φ r \ H (- ¹ - f P P-- CQ Q o μ- rt Φ p. Ei rt H- CQ li Φ Pi c CΛ Φ ii> • Pf H- li Ei PJ CQ ⁴ Φ H 0 TP er CQ P

H- Φ -Sl 3 PJ = li Φ 3 3 f PJ EJ D. SU: Φ 3 ü P 0 tr Φ J • d ω Ω H- s- Φ φ IQ E ^ Ei E ^ D. <! D- rt 3 Φ 0 CQ Ei 3 NP CQ PHP φ l * ϋ o H- H Φ J u Φ 0 PJ 3 * Ö φ φ CP rt Hi Φ C ^Q μ- φ ti

3 rt CQ PJ li (- ^■ O h- ¹ li & i C> s: φ K • Ö ii Ω H 3 CQ PJ j rt Ω 0

H- P Di Ω φ f σ er rt CQ tu i φ Φ ET CQ P tU: Di li ω Φ tr Di rr P H- tr ^* H- P 2! DD Φ rt DD Hi D. H- I- ¹ 2! C 3 Ό Hi D. Ω PJ PJ: 0 ii Φ P

IQ Φ φ H- PJ D. H <& PJ Φ Φ φ Φ N CQ u Ω μ- 0 ⁴ CΛ 1S1 μ ^J <P Pf

3 CQ p 3 Φ Hi φ Hi 0 CQ Ei 3 ii li Ω Φ Hi Ϊ rt PJ H Di μ- μ- φ Di et

H- IQ Φ H- l Φ CQ t- ¹ ii rt - f 0 H- Φ P 3 Φ CQ CQ ei Φ rr Φ ii tr Pf rt li tU: i PJ <> x) Φ li rt ii 3 t? φ Φ ii φ φ μ- i * d 3 2! tr φ ei CQ ö Ω H- E5 tr Φ i Di li H- CQ H- <1 P. P li 0 μ- u J

CQ PJ <H- 0 ≤ ei T Ω D. U: li 0 H- μ- CQ rt J P σ SS P φ Ω ι-3 Hl

(D 0 D. CQ Φ 3 0 Φ E Ei er D. Φ 3 Ω 3 Pf Φ P Φ Φ? R ii Φ

H- rt H φ. »H- Di rt er CQ H- C H- E? R H- td Φ • i J Hi li φ td P PJ: ii

3 Φ H p 0 Di rt e P. CN φ P Pf D. rt rt h- ¹ rt <μ- ii CQ er φ Hi μ- ü P CQ

(DP H- T Φ φ Ei ≤ Ei Di et Φ C φ PJ φ er - Φ tr ^> PP Hi CQ Φ Φ

»1 Φ Ω 2: H- P Φ er H IQ D. φ li Φ Ei σ Φ f ii μ- er tU: et P μ- ti H T PJ CQ H- Ei 5; J H- CQ Φ H- c £ P Φ P φ CQ • ö P <! 3 CQ

0 ⁾ 13 et rl Ω r Ei Pi IQ N H- J Ei Ei - Ei μ- Ei Di P CQ Φ i 0 tu rt

? ii P Φ tf PJ Φ 0 Φ ≤ t ⁾ <J Hi rt Φ N Di CQ Φ CQ Φ μ- er P PJ PP rt rt 0 3 H Φ 3 i T} H- 0 φ ti C Φ Φ CQ P CQ Φ PP Φ μ-

IQ 3 P ¹ Ei i J 3 li φ μ- φ CQ P Ei P ω

ω W t M H,. μ>

CJ1 O σι σ (1 σ Π

D. D. CQ CQ <21 CQ Di CQ ET D. D. tr Hi rr Ω ti μ- rt α P = 2: s Pf Ω <Di ≤ μ- rt CQ Ω <!

Φ 0 φ Φ PJ PJ rt 3 tu μ- PJ μ- u PJ H Φ tr μ- P μ- 3 er tu ti PJ u PJ Φ μ- P Φ Φ tr φ Φ

CQ * d li ii Pf Hi μ- Ω μ ^j φ CΛ H PJ = Φ Ω CQ Φ Hi 0 P CQ Pf 3 ti μ- μ- Φ μ- P

• d μ- P Φ Hi i CQ ET rt rt Ω CQ tr φ Φ ti Φ i P * d P D. Pi rt ι-3 Φ Ω 21 P ti rt μ- μ- φ * τj Di Φ tr μ- tr et μ- Pf μ- ΪS ti P • 0 P Hl Φ μ- P co Ω ti tr PJ 3 CQ Φ φ Φ PJ D. P = Φ <φ P Φ PPP μ- Pf 3 ti PJ 3 Pi CQ μ- rt he

PJ: CQ et Hl tr CQ P Φ tr ii 0 P. ü P φ Φ P P et M CQ tr tU: r-> μ- φ u Φ

CQ Φ Φ φ PJ J D. Φ μ- Ω ii ti • d PJ CQ ti er CQ P μ- rt PJ CQ CQ Pi φ? Pi P left

Φ μ- et ii P Φ P D. Pf P ⁱ τj ti 0 PJ P φ μ- Φ Pi s. P Φ r-> φ PJ CQ φ r H li rt φ rt CQ ei CQ Φ Φ PH μ- CQ P CQ ^> P Ω P PJ li et ti i CQ φ Φ μ. μ- rt Φ Φ μ- Di P CQ 0 Ω μ- Hi HP = P Pi tr er Hi ≤ Φ u ti er CQ 0 U:

2! CQ S li <0 <Ω μ- CQ D- tr rt J tr ω φ Φ f Φ Φ Φ PJ ti 2! CQ <φ Φ Pi Ω

PJ PJ = 0 li J T φ τι PJ CQ P et μ- i CQ Hi P ti PJ μ- ti μ- P P PJ J Cd P rt Φ tr

Hl f H CQ H Di Pf φ CQ P = P rt f P 0 Φ Φ P P: Φ P Pi rt Hi P H <! Pf ii P. N li (0

Φ PJ rt K P P ti Φ ET rt μ- et P P ti P P tr Ti CQ P CQ μ- φ CQ Φ PJ P Hi φ Φ

H Φ CQ - μ- Φ P Φ ii ti 0 Hi CQ μ- CQ ei 0 φ P ti Di ti f P μ- P P u ti

CQ tr Φ Ω rt 3 P 3 rt 2. Φ <P CQ P H P μ- φ Φ tr P 3 P P tu φ Di tr. He. > P PJ Φ PJ tr ü tu P CQ P μ- & P rt Hi ti ii Φ CQ P Pi ^ f Pi Ω

PJ P P Φ et PJ P = P CQ rt Hi Φ rt Pf P. rt CQ φ CQ Pi μ- ti> i Φ 3 μ- P 0 0-- Φ tr

P D. P l P Ω tr CQ CQ μ- <Φ li ^• »P μ- CQ Φ cQ φ <D. P tr PPP ei

Hl φ Di PJ P rt ti Hi CQ ω 0 li u P Pf Hι Hl Pi rr • d μ- 0 0 P J CQ μ- P Φ P

P i CQ Φ Φ P P = er Ω P P ≤ 3 0 rt 0 Φ N f φ ti • d rt 3 Pi φ φ P

D- rt μ- <P ET μ- ET P CQ fU: tr ti φ ti CQ φ J 3 rt • d Φ rt μ- φ μ- P «rt

Φ * l P μ- Ω 0 CQ li Hi Di P li tr PJ μ- 3 PP φ Φ φ ti Φ rt ei C ^Q μ- - 0 φ

3 0 Hi PJ P ET ei P et P Φ CQ PJ H μ ^j CQ P) ι-3 er 1 μ- Hi P rt PPP

P P N ei N P φ P ti Φ CQ φ rt Ω P Pi ti PJ φ tu CQ tU: i <er rt

Ω μ- PJ CQ CD Φ μ- P CQ P D. tr rt P Φ tr Hl Φ tu = Φ PP φ ^ Φ u cd Φ PJ CQ tr Φ ET Φ φ μ- Ω CD <μ- • D- <" > ti CQ CQ Hl Pi Pi μ- μ- 3 Pf Pi Φ <3 Φ

P 3 0 N rt tr CQ Hl N • d PJ P 0 CQ φ φ μ- rt rt ti P PJ ti 0 μ- ti

Ω o Φ ti P μ- et Φ 0 P f D. α i ü Φ Pi M ti T) ii Φ μ- D. Di PEJP = ei P μ- f Di CQ QP = SHJP Φ μ- μ- μ Hi μ - ti H μ- CQ QP _^ Φ 3 tr u Ω

Φ D. P P U: 3 <P P t Φ Φ μ- 0 Φ Hi 23 0 Φ • r] P Φ P ti? PJ ti i rt Er

CQ i Φ Φ PJ CQ CQ ET Φ * d 3 rt CQ Ω ti μ- PJ Pi 0 ti f DD PJ PP μ- μ- rt μ- CQ rt P μ- ii f ti PJ ET φ 1 ET 3 CQ P Hl P ^ Φ ⁱ τj 3 et P Φ 0 Φ

Ω J - Hl P μ- H 0 Pf li u P 0 rt rt φ D. φ f 0 μ- er <Φ CQ ti μ. 3 O CQ P et tr P j 3 Φ P PJ PJ - ^> PPPPP ti et M φ CQ 0 er μ- 0 Φ 3 O CQ

Φ Hl li Di D. μ- μ- P -> et Di PPP CQ Pf P CQ μ- rt li φ Ω * υ i ti tu f tr • d μ- ü 0 PJ Φ D. fö ω CQ et H Φ 0 C ^Q CQ μ- e CQ 2! φ 0 PJ> i P tr ei P et 0 Φ J CΩ

CQ D. Di tΛ P μ- u r Ω Φ φ <D- ti CQ P φ N PJ tr P μ- Di 0? Pi μ- 3 ii li rt φ φ P Φ P Φ tr P 0 Φ Di * d 3 Pi Ω Pi P Hi Hi ti P- Ω φ Hi Di rt P CQ 3 Hl rt -

CQ li Pf Φ Ω Di P H P P H- μ- • tr μ- Φ tu-. Φ tr P P ti Ω r μ- rt et μ- ET Ti er * »CQ 0 PJ ti P P rt rt r φ CQ ti H N et PJ f 2! Ω tr • PJ: Pf CQ

Φ f P P P = φ φ Di er μ- 0 P N α Φ CQ s; P ^ fl Ω et tu T Ω Φ 0

H μ- ¹ 21 φ Ω tr ii CQ Hi Φ Hl Ω Ω CQ Φ μ- μ- PJ <≤ rt φ μ- P 0 tr Hi μ- cd tr

H Φ PJ Pf ei φ μ- 0 ii PJ E tr tr φ P PJ tU: J • D- CQ CQ 21 Φ P μ- Φ Pi rt er Hl * d ** P μ- PH rt tr J ei C ^Q CQ Pf tr P Φ Ω μ- 0 PJ ii & P PJ tu

Φ Φ ti P Ω P- 3 NP CQ PJ P Φ Φ P ei Hi C ^Q - μ- φ tr Hi • d Pi 3 P ta μ- PH tU: Di CQ ET rt P Φ P φ rt CQ ti μ- P φ CQ ti Φ tr P Φ 53 μ- Hi

CQ D. CQ N Φ CQ Di P CQ Hi TI tr 3 φ Pi <P rt PJ Φ ti PJ = 3 3 Φ rt CQ rt φ μ- μ, CQ Di μ- CQ <! P = D. Pi X P = ti tr μ- Φ Φ - er P »d μ- Pi μ-

• P PJ CQ et Φ φ μ- Φ f J tr Φ φ 0 tr Φ u CQ ii ti 13 CQ <CQ Φ> et Pi φ Ω

P φ D. μ- CQ P t u 3 ii P ü P ü μ, rt ^ ti Φ φ O Φ P P φ Φ ti ET

Ö co Hi φ Hi TI D. f P rt PP rt φ er JO tu rt D. PP CQ H • i μ- Ω PP rt Ό P = • P <<<CQ P 0 Φ P Φ P P. tΛ N Φ Pi CQ Φ φ O Pf

Φ tr D. P Φ li tr φ J D. 0 PJ CQ CQ er <•> μ- rr P Φ CQ CQ Φ P ii er er φ

CQ μ- φ Di ι-3 0 ei 3 f P li ^ ti CQ Φ 0 Pi Φ f Pi P Φ P = ti er Φ φ μ- φ Ω li H Di Di P 3 0 P ii rt PP CQ ti ei - t CQ P et Φ μ- er μ- <μ- ii P

CQ ET PJ PJ: Φ PP Φ tr P Ω Φ PP rt Hi Φ φ ti P Φ P μ- 0 Pi Hi Φ rt P t Pf CQ PP 3 ET μ- 3 Pi μ- μ ^j μ- μ- φ li CQ Ω ti ti

CQ et CQ Φ μ- ¹ 1 Hi tU: ω ii Φ Pf fU: 1 1 1 1 rt ti

is achieved on the one hand by a precise merging of the vacuum chamber cover with the vacuum chamber and on the other hand by the exact insertion of the product wafer between the guide pins.

To control the individual process steps, vacuum valves are provided in the vacuum lines and in the connections between one or more evacuation devices.

In a further embodiment of the invention, the device comprises a first vacuum valve between an evacuation device of the vacuum holding device and the vacuum chamber cover, a second vacuum valve between the evacuation device for the chamber volume and the vacuum chamber, and a third vacuum valve between the evacuation device of the chuck and the chuck. With these vacuum valves, the individual process steps can be controlled and the positions of both the carrier wafer and the product wafer can be handled safely.

In one embodiment of the invention, at least three guide pins are arranged on the vacuum holding device, since three guide pins can be used for clear fixation in the X and Y directions. An improved version of the device provides that at least five guide pins on the

Vacuum holding device are arranged. With five guide pins for each wafer, it is securely secured against slipping, tilting, moving or moving in any other way.

Another embodiment of the invention provides that the guide pins have a length which corresponds at least to the thickness of the product wafer plus the distance between the product wafer and the double-sided adhesive film or the adhesive layer, and which is less than the distance between the

Surface of the vacuum holding device of the vacuum lid and the surface of the chuck is. The distance between dimensioned the product wafer hanging on the vacuum holding device and the carrier wafer lying on the chuck so that a safe vacuum drying of the opposite surfaces is possible, so that the double-sided adhesive film can completely outgas on its surface, and the product wafer on the opposite side has a completely dry surface and no gases are present after the evacuation of the vacuum chamber between the surfaces to be glued. The distance also depends on the size of the opposite surfaces. The larger these areas are, the larger the pumping cross-section must be chosen and consequently the distance between the wafers must be set. In a further embodiment of the invention, the distance for 6 to 12 inch wafers (150 to 300 mm) is between 3 and 15 millimeters. For wafers up to 6 inches, the distance can be reduced to a millimeter.

Another embodiment of the invention provides that the guide pins have a diameter of 200 μm to 1200 μm on their cone base and a diameter of between 100 and 500 μm on their cone tip. Such slim and thin pins have the advantage that they are extremely flexible and induce the lowest possible stresses in the product wafer when guiding the product wafer.

In a further embodiment of the invention, the vacuum holding device has depressions which can be connected to an evacuation device via a first vacuum valve. Such depressions are formed as concentric grooves in the vacuum holding device and have in it

Groove holes on which communicate with the evacuation device for the vacuum holding device. This embodiment ensures that the back of the product wafer is subjected to a large area of vacuum and hangs flat on the surface of the vacuum holding device on the vacuum chamber cover.

P i ^j ti H ti Ω rt CQ CQ CQ CQ ii H Ω 0 P CQ i Di P μ- E ii Di P H3 2! rt Ω Ω td

P P J- fU: P P P = tr μ- μ- Ω 0 μ- P P ET Di PJ φ Φ Φ Φ CQ PJ P P μ- ti PJ Φ tr ET μ-

Di Pf CQ PP tr p 0 Ω Er PPP CQ P Φ ET 0 CQ CQ P et r P f Ω PJ: Hl Φ PP et CQ CQ CQ Φ ii Ω P ET φ Di D. CQ er Ω li 3 ti • φ CQ et tr CQ Φ Pf ti Ω φ

Hi 1 μ- Φ CQ μ- Φ Pf μ- Φ P Φ CQ φ Pf Φ D. Ω t. Di P CQ 1 et φ li 0 = Hl Pf

HS! CQ CQ PP CQ φ ti ti CQ CQ CQ tu P ET H. μ- td CQ 21 ti P μ- ¹ £

PJ = u PJ rt Φ • ii N D- P μ- rt 0 CQ P i Φ P 0 φ φ rt PJ P = 1 CQ P PJ. t. φ

Ω Hi P μ- ti er P P Φ φ μ- P μ- Hi φ rt Ω Di CQ μ- D. μ- Hi er 21 Φ Φ Ω 0 μ-

ET Φ D. Hi Hi N P CQ P CQ Hi Di Ω CQ - Pf P φ μ- Hi Φ φ PJ CQ P tr CQ rt

Φ ti PJ rt r ≤ CQ et 0 P rt Φ tr D. CQ Pf Φ rt ti ti Hl et Φ μ- φ

P CQ J Φ Φ CQ Φ 2. H μ- Φ ii φ φ TJ D. et P = 0 Φ Φ J JU: r ti f CQ H <CQ HJH Ω Φ t ti ti J μ- 1 tr P CQ CQ Di l H ET Di μ- Φ

0 P μ- CQ N 0 D. rt r-> Hl rt tr P = CQ 0 CÄ P 21 φ μ- Φ PJ Φ μ- rt P φ 0

P μ- φ ^> ii Φ μ- Φ Φ Φ et er €, Φ Pf Di PJ ti CQ ti P Hi Φ CQ Φ CQ P

CQ Ω Di μ- ¹ N ti Hi P li P φ Φ CQ P Φ c Hl Ω μ- Ω P = Φ rt μ- μ- P ti ET μ- μ- μ- P rt P ti ti P rt Φ Pf μ - Φ φ Di ET P tr ET er et PN ti Φ φ Q ti S CQ Ω Ω Φ ω

P rr P φ P CQ CQ Φ D- P P φ Φ CD ET ET ti Hl

Φ D- rt Φ D. μ- μ. Di φ 1 φ P CD P ti Φ N rt CQ r Φ P P P:

P er D. ö ii Φ CQ Pi PJ μ- Φ μ- CQ HP 21 CQ li ^ rt Φ μ- S Ω P ET rt φ μ- μ- μ- P Φ μ- tΛ Φ μ- φ 0 rt D. tu> the H3> £ PJ PP μ- Pf CQ ti μ- Φ Ω CQ P φ cQ α P ≤ φ Hi ti PJ Φ ei PO μ- φ P φ CD CQ P

N rt CQ Pf Ω P = $. φ μ- l_l. 0 μ- P Φ PJ: P μ- PJ = CD Di P ti Di CQ CQ P

P ii Φ Φ tr P er Ω Φ P Ω <! φ ET CQ ti N Hl rt CQ r Φ Di Di CQ μ-, Pi ET rt CQ

3 PJ li CQ Φ er D. Du Pf 0 ≤ rt CQ CQ μ- ti φ μ- ti ii Φ CD P 0 μ- φ μ- CD

CQ i PJ Hi li φ Φ Φ Φ ti φ • Ω CQ Di PJ ti μ- P rt D- 3 φ li Hi Hl

TJ Φ> Φ P P = H ti> i P rt μ- »τ | tr J φ μ- CQ 1 D. CQ CQ • »i • μ- PJ rt 0 li P P CQ CQ tr μ- Hl D. Φ H P = μ- P φ Φ 2! P Ω Φ rt »τl P φ li

0 CQ CQ ti φ D. Φ μ- μ- tr Ω Hl P P PJ P Φ ET μ. Ω P = CQ 3

Di Hi> -3 Φ P cQ pj: μ- & CD cQ μ ET P <• Hl Q μ- Φ P Pf & CQ ET ti PJ

P CQ P = left P Φ Ω Φ CQ T Φ P et i PJ φ Ω CQ φ Di ti PJ P p. c

Pf 0 tr tu-- μ- CQ P Er rt 1_J. u PP Φ Pf σ ti Di Er ^ 0 Φ Φ P CQ Hl Φ et P ei CQ C ^Q Di Φ ^ PJ Φ Hl CQ Di H PJ P PJ Φ O «N ii μ- P Φ sS ti

1 P. P Φ P. Hi Φ P P = P S rt s. CQ Φ P P N ET ti D. li φ £ Φ Ω CQ P Φ

21 φ P li φ 0 P ET D. Φ Φ PJ CQ CD D. CQ 3 P μ- Φ 3 μ- μ- ti ET CQ • μ- t

PJ ti CQ 1 rt li Pi ti H- ti Hl et 0 CQ ET P ⁱ rj »i Φ rt C ^Q CQ Φ CQ CQ ti

Hl P CQ 21 3 <Φ P P Φ μ- Hl> d φ PJ CD PJ 0 P Ω Φ rt ö et Hl

Φ Hi PJ P PJ CQ P μ- μ- 21 ti Hi ti • d ii M μ- P CQ ü Pf ET μ- <μ- μ- μ- ti D. 0 Hi P CQ Pf CQ Ω CQ φ 0 rt tU : Φ μ- rt P CQ μ- μ- PJ 0 = φ rt O Hi Φ P

Φ ti Φ Di μ- P CQ CQ ET Φ μ- er Φ CQ Ω Φ D. CQ rr Ω PPP CQ ti rt CQ Pi Pi JP 3 ei PP Φ C r P CQ Φ φ CQ tr <1 rt μ- f Hl P rt φ φ μ- P

P CQ ≤ D. 3 CQ rt φ ti PJ li φ et 0 Di Φ 0 Φ $. Φ m 3 Φ φ P

IQ Hl N Φ ET Φ μ- P = 21 Hi 1 μ- Φ ti μ- ET P Φ P ti P μ- Hi • ti CQ ti H P PJ μ- Di PJ P Hi er u Pf M CQ 2; rt rt ti φ φ μ- Di μ- PJ:) P = 0 CD μ- PJ: ti P CQ μ-: rr Φ Hi O J: tu μ- φ μ- P φ Φ CQ D. C φ ii CQ φ CQ

Ω CQ Hi φ φ et er Φ H Φ ti Ω u Hi CQ Ω V ti CQ Φ μ- φ D. μ- P μ-

ET Φ n • P Φ Φ CQ li μ- ET P Φ S ET 0 PPP Φ ti Φ tu Pi rt f φ rt ti P ^: n-. <ti P Ω CQ CQ φ Ω ti Pf rt CQ PP ι-3 1 ti P Φ μ- ti tr

Φ 1 ET α Φ 0 0 r-> 0 ET Ω P tr CQ r- ¹ P μ- D- CQ »i P * d 2; Ω P 0 φ et

P 2. ti μ- μ- CQ li μ- Ω li> d ET Φ PJ P rt CQ P): P 0 PJ Hl ET P Ω

• PJ P φ P μ- ti Φ tr Φ H ET ⁱ n PJ er CQ CQ μ- N CQ CQ Di CQ Hi ti TJ μ- ET <

Hi P CQ Φ rt μ- CQ μ- P CQ μ- 0 P Φ φ 0 P rt φ μ- Φ PJ = Hi φ rt 0

Φ CQ φ μ- Ω φ D. rt CQ Φ P CQ Hi P i P 3 μ- ti Φ rt H CQ P = O ti ii ti CQ CQ 0 ET P μ- φ Hi u μ- Di P Φ CD Hl 1 μ- μ- Φ ii P. PJ

Di Φ P rt p. φ P D. 0 P rt Di Φ P • i CD tSJ rt 2; P 0 P ti P P P

Φ Φ μ- ii μ- P Φ • »Φ ti CQ μ- Φ P D. J rt P Φ J Φ P P 1 Pi Pf CQ Hi Pi

X CQ CQ μ- φ P P ^ 3 3 μ. 0 3 ti μ- Hi Hi μ- D. 2! Φ et CQ u

PJ rt P 1 CQ OP et PJ P • r] rt Hi P = Pf Φ tr ¹ Φ tu P 1 CQ Pi LΛ

Pf ⁱ -d CQ CD 3 N - CQ μ- 0 P rt tr 0 = H tu = 1 ⁱ n Hi rt Φ et ti N Φ er μ- φ φ Hi PJ Φ ei P CQ P μ, Φ μ- li Pi 0 P li φ 1 μ- P 1 μ- 1 P Φ 1 CQ 0 Hi Φ

I 1 Φ 1 i Φ 1 P φ 1 1 ti

If the sum of the lengths of position pins and guide pins together exceeds the distance between the surface of the chuck and the surface of the vacuum holding device, in a further embodiment of the invention the positioning pins are offset with respect to the guide pins with respect to the edge of the wafer to be connected. This also ensures that the positioning and guide pins cannot collide. Both the chuck and the vacuum holding device have attachment options for the positioning pins or guide pins, which allow adaptation to the respective size of a wafer.

In a further embodiment of the invention, the device has a heater which is arranged on the chuck and enables the chuck to be heated to between 60 and 200.degree. A further heater can also have the vacuum holding device in order to support degassing of the surface of the product wafer.

A method for the planar connection of two wafers for thin grinding and separation of a product wafer, wherein the one wafer is a carrier wafer with a double-sided adhesive film or with an adhesive layer and the second wafer is a product wafer, has the following method steps on:

Pulling the double-sided adhesive film or the adhesive layer onto the carrier wafer, inserting the carrier wafer between positioning pins or pins on a chuck of a vacuum chamber,

Inserting the product wafer between guide pins of a vacuum holding device of a vacuum chamber cover and fixing the product wafer by opening a first vacuum valve which connects the vacuum holding device to an evacuation device,

Close the vacuum chamber and evacuate the vacuum chamber to an equal or higher vacuum than the vacuum irj Pi CQ PJ α rt 3 er HPJ Φ rt PJ li PJ CQ P CQ 21 Di N Di EP Pf 3 α ti Φ Φ Φ P Φ μ- Φ Φ P Φ P μ- φ P μ- P rt 0 rt PJ φ P Φ o = 3 φ μ- μ-

0 μ, P P H ii CQ P μ- P rt Hi P μ- Hl Ω Hl μ- Ω μ- Hi 3 CQ ti ET Pf M rt φ

Di μ- N Pi CQ φ ET CQ Hi ET Hi Φ Φ Φ PJ rt CD

P <; D. φ id Pf P Φ CD μ- Di 3 Di rt ti rt rt ti H t, <ti 3 ET Φ φ f 0 Φ & CQ P tr P • d CQ Φ φ PP Φ r Φ ii PJ u Φ 3 PJ : co CQ rt rt ω D. et CQ CQ Φ 3 Φ li ET et 3 3 PP - Φ P. PJ = P Pf CQ Φ P rt μ- μ- Φ PJ Φ

1 rt P O tr μ- Ω PJ - & J CQ P- μ- CQ P CQ i P ti CQ Pi <Φ Q Pf ti

21 CQ td J D- Λ φ P tr CQ Hl CQ cΛ Hl $, 3 φ ti φ rt P <Φ φ φ μ- φ φ P: P

P rt PP Φ PP CQ Φ φ CQ li rt li P μ- μ- Hl Ω ti Φ 3 PJ PP ti ti CQ 3 Hl P <

Hl PJ = et i Φ i Φ ti Φ PJ = PJ fU: P ET Φ ffi P = ET 1 ET Pf P D. Hl φ P rt 3 PJ

Φ P CQ PH Φ P Hi Di tr CQ P φ CQ P. ii Φ ET 2! Ω JP P. <i JPOP Φ <f ei D. JNPC ti P. H Φ PJ Φ i ti φ φ 0 ti ti D. J tr HP CQ 0 ET Pi μ- ¹ D. P Φ P μ- CQ € Di Ω Φ PJ = ti li ti Pi ii r P rt μ- Hl Φ rt 3 td Φ P ti Φ u PP

P CQ Φ μ- ET »- P Ω rt 1 N Ti 1 Φ φ P Φ φ H Φ <! ET φ P P Ω = D. rt 3

P Φ P CQ PJ P 0 - <Φ 21 P ti 21 ii F P rt ti Hi <! J PJ u Pi P φ Hi Φ μ- tr

D. P CQ Ω P μ- H "Ω φ PJ P PJ ii 0 PJ PJ = Φ CQ ti 0 Pf Φ α P Hi ti PJ tr Ϊ rt μ- er P Pf Hi D. Hl Ω P u ti 0 P Hl PJ = ti CQ P rt li ET ti P CQ H ⁴

Pi td P φ PJ rt φ Φ P $, Φ Ω P φ tr CQ P Hi P PJ = Ω ii μ- φ PJ P> φ <- rt

0 <P P Ω H <! P Φ ti er f ti φ Φ CQ PJ P- D. ET μ- Di φ P <rt Ω P P PJ Φ

• d u D. ET N <Hi O 3 ti - φ et • ti Q u Φ Ω PJ ti Φ u Pf Hl Pf <

• d Pf D. CQ Z PJ H f Di ti 1 Hi Pi φ CΛ P rt ET CD Φ f Pi φ <! P 0 φ P Φ Φ μ- Pf PJ: J Φ D. Hl 21 21 H "Φ Hl φ 3 • Pi rt PT) P Φ μ- μ- 0 P ei μ- u PP CQ P Ω CQ 3 P Φ J Φ P): PP = P Φ Φ P <ei PPPPP 3 ti

CQ φ f Di Ω P T rt 3 ii PJ = Hi μ- Ω ET ii CD td ti P J Di 0 3 PJ Pf μ- φ μ, P tr Φ ET 3 φ PJ: Φ f Ω Φ rt ET li <! Φ φ CQ Pf Φ Pi ET <Pi P ω tu Ω μ- PP Φ Φ CQ PP ti PJ CQ ET li Φ Φ & rt Φ CQ μ- μ- Pi PHP u 0 Φ P. φ 3 ET rr P 3 μ- P Φ D. P Φ φ ti CQ - ii μ- P 0 JP Pf ti H Φ 3 rt μ- CQ et D- J rt <; μ- Di P μ- 3 ET P. rt Pf Ω Φ id er 3 <et rt rt HP: φ P cQ μ, φ f Pi ii o Q φ ^ P Pi μ- μ- Φ PJ fu ET P μ- » Hl tu 1 Φ Φ <• Hi HP o

D. 0 P P φ O P H φ Φ rt P H P o P φ φ PJ = D. f 21 <μ- J H rt CQ

Pf Φ Ω P P Ω φ CD ti H Pi P rt ≤ TJ CD Φ P PJ O f Φ P P

CQ f Ω 3 Pf t. P CS3 0 CQ CQ 'P. μ- Φ Φ J φ CQ H ⁴ ti P Hl li - P CQ P u D. φ P tr tr ti ti et ≤ φ Pi Φ PJ 0 N CQ rt Pi P 3 φ rt 3 Φ li P CQ CQ Ω P er N φ Φ Di Φ Φ 0 CQ μ- Di μ- 0 μ- et> d 53 Ω • Φ Di μ- <Pf li μ- Pi 3 Φ CQ ET H

Φ ΪS P ü Φ μ- rt P. J CQ PJ rt • d P -5 μ- ET ii rt P PJ J Ω PJ Pf P 0 = Ω

P μ- CQ Hi ti Di P CQ Ω tΛ CQ * d Φ Φ CD α PJ PJ μ- P f 3 P ET CΛ tu Hi CQ ET

Pi CD Φ ΪS f φ tr Φ li μ- -> Ω CQ PJ CQ P CQ Di P 3 PJ rt 3 Pi Hl Ω

Φ Ω CQ (U: <P Φ et P φ S. PJ μ * φ CD p- φ N φ CQ HP Φ Ω P 0 3 Φ P ET Ω = ti tr 0 Ω u ti 1 P PJ: P CQ u CD Φ φ Hl P μ- Φ Φ f CQ 3 ti ET P ET Φ ii P Hl

ET s ET Pf Ω D. 21 Pf ti ET Hi Φ f Φ μ- P 0 rt 0 P μ- ET CQ P ti P μ- Hi

• r) P μ- Φ P er Φ PJ PJ PJ li μ- et CO rt ti CQ li φ Ω J PJ CQ Φ • 21 CQ φ P

0 li Φ P P φ P Hl P P φ D. et μ- μ- Pi 3 μ- μ- Di ΪS tr ET M P Ω PJ PJ Φ IΛ> Φ

M PJ 3 ti Φ P 3 P Φ μ- <1 <CQ φ rr P Ω P μ- Φ rt Hl ET 3 3 Hi P φ P μ- P i Di Pf Hl ti Di 3 cQ Φ Φ ti Pi ET Φ ti P * d Φ Φ Φ P φ 3 Φ Φ JPNP ii Pf P rt D- Di M <1 CQ μ- <Ω ti P Φ

Φ 3 P 3 PJ: P P £ D- Ω Pf Hi <P Pi <Φ φ u 0 φ PJ ET P Di μ-

PJ CD 3 Ω P & μ- Φ ET Ω PJ φ u Pi μ- Φ P D. P P li Φ Λ Pf PJ Pi et Φ P

P cd td Φ ET Pi CQ ti P φ er ET r f Φ H Φ ti μ- Φ P P P Φ ti Φ

CQ N ii li ti φ D. Ω Ω r φ ti φ PP = CD • fl ti • n PJ μ- Ω PP μ- ii li CQ φ S Hl Hl P Pi μ- tr M Pf φ ii Φ PP er ^ Ω P = 0 P Ω ET 3 D Ω <

* d μ- 0 0 Pf 0 Φ Φ P Hi P D. 3 φ P = ET E χ) Hl Er φ Pi Pf Ω ET CQ PJ N

PJ CQ ti ti PJ Hi • d P PJ u Pi φ ET ii ET μ- ti ei μ- rt CQ Φ J tr Pf sS

() Ω C D. PP = VN Pf P φ PJ: D. P PJ tr ti Φ P 0 φ Di P ei 3 Φ Pi Φ P Φ et E Φ Φ P li φ P Di P CQ P Ω Φ ti P tr P P. μ- P 0 3 Φ μ- P μ- φ ti ti CD Φ μ- Φ ET P ^ rt P = P rt CQ P PJ Φ CQ D. <Φ KP Ω 3 rt

ΪS P P P D. D. CD PJ P φ 0 • rl Φ 0 Φ Ω CQ '- CD Pf P Φ PJ ii μ- ET <1 Φ

Φ μ- μ- P PJ Φ 3 1 H 0 <<! f CQ 1 and Hl μ- <! ti Pf Pi PJ N Φ P ei CQ co ti CD μ- 1 Di μ- 0 μ- 0 φ 1 ET 0 P Φ Hi P Φ P 1 1 Ω 1 1 μ- P ti φ ti P 3 PI Pf CD 1 μ - 1 tr φ 1 1 '1 1 1

the. The pumping cross section in this case is the lateral surface of the space between the surface of the product wafer and the surface of the double-sided adhesive film along the outer edge of the product wafer. The pumping cross-section is thus determined by the distance between the product wafer surface and double-sided adhesive film and the size of the product wafer. Another advantage of the device according to the invention is that the pumping cross section can be adapted to the requirements of the process by increasing the distance between the product wafer and the double-sided adhesive film. It is thus possible to reduce the pumping time and thus the production time with sufficient capacity of the evacuation device to increase the pumping cross section by increasing the distance and to reduce the pumping cross section if the pumping time takes longer due to the reduced capacity of the evacuation device.

In an implementation example of the method, the step of thinly grinding the plan-adhered product wafer to a thickness of less than 100 μm is additionally carried out. This thin grinding can be carried out on the basis of the method according to the invention of connecting a carrier wafer to the product wafer to be thinly ground with thickness fluctuations limited to a few μm over the size of the product wafer area in a corresponding thin grinding machine. Any deviation in the planar connection of the two wafers from their plane parallelism affects the uniformity of the thickness of the thinly ground wafer. However, since the active surface of the product wafer is placed under vacuum on the double-sided adhesive film due to the method according to the invention, residual gas cushions form gas bubbles between the wafers, which could be the cause of a non-planar connection between the product wafer and carrier wafer. locked out.

In a further exemplary embodiment of the invention, the product wafer, which is thinly ground to below 100 μm, is placed on a dic- ke thinly etched up to 15 μm. This variant of the method has the advantage that etching-mechanical thin grinding is not maintained when the wafer becomes increasingly thin, well below 100 μm, and a transition to pure thin etching without any mechanical stress is made for thinning to 15 μm. After the product wafer has been thinly etched, it is still connected to the carrier wafer, so that it is mechanically supported by the carrier wafer.

The product wafer can be separated into individual chips both with and without an adhering carrier wafer. If the carrier wafer is separated from the product wafer before the product wafer is cut or sawed into individual chips; the product wafer connected to the carrier wafer is previously glued to a saw frame stretched with film and then the carrier wafer is heated by heating an excessively dissolving temperature for the film or the adhesive e.g. heated to chucks heated to at least 120 ° C. to remove the double-sided adhesive film and to remove the carrier wafer. The thinly ground and etched product wafer can then be separated into individual chips in the clamped saw frame. The dissolving temperature is understood to mean a temperature at which the adhesiveness deteriorates and detachment of the product wafer from the carrier wafer becomes possible. The dissolving temperature may well be below the melting temperature of the double-sided adhesive film or the adhesive layer.

In a variant of the separation process of the thinly ground product wafer into individual chips, the wafer composite comprising a thinly ground and thinly etched product wafer and a carrier wafer is first subjected to a separation step in which the thinly ground and thinly etched product wafer is separated into chips, and then the entire composite wafer is glued to a carrier film, the thinly ground and thinly etched and now separated chips being glued to the carrier film. In order to remove the carrier wafer holding the chips, the composite of composite wafer and double the adhesive film on the skin side is heated to the melting temperature of the double-sided adhesive film and the carrier wafer is removed from the overall assembly, so that the thinly ground and thinly etched chips are then glued to a carrier film for further processing. This method has the advantage that the cutting of the thinly ground and thinly etched product wafers in chips can be carried out using a sawing method in which a wafer is divided into chips.

A further variant provides that the product wafer is provided on its surface with saw grooves, which already cover the surface of the product wafer at a depth of up to 100, before it is introduced into the device according to the invention for connection to a carrier wafer Partition μm into individual chip areas so that after the product wafer has been thinly ground and thinly etched, it is automatically separated into individual chips on the carrier wafer.

The method according to the invention thus has the advantage that all three variants of cutting a product wafer into chips can be carried out using thin grinding and thin etching of the product wafer. The method according to the invention of the planar connection of a product wafer to a carrier wafer by means of a double-sided adhesive film thus improves the chances of success of thin grinding, thin etching and dicing of a product wafer into thinly ground and thinly etched chips.

Thus, with the method according to the invention, product wafers and carrier wafers are bonded in a vacuum chamber by means of a double-sided adhesive film. A ground dummy wafer can be used as the carrier wafer. The double-sided adhesive film is used as the connecting adhesive. First, a carrier wafer with the adhesive that later connects the device wafer or product wafer and the carrier wafer is introduced into the chamber. Conical pins are used for centering the product wafer and carrier wafer without misalignment. The device wafer is drawn in by vacuum on the back of the wafer (vacuum 1). The chamber is then evacuated (vacuum 2). By equalizing the pressure, vacuum 1 loses its holding force and the product wafer falls onto the carrier, guided by the tapered pins or guide pins. Subsequent ventilation then uniformly loads the product wafer and presses it onto the carrier wafer, which leads to a firm connection. No stamp is used to press the device wafer.

Thinning product wafers far below 100 micrometers requires a carrier wafer which is firmly connected to the product wafer during thinning and gives it the necessary stability. Dummy wafers or ceramic wafers can be used as materials for the carrier wafer. It is cheapest to use a pre-ground dummy wafer as the carrier wafer. The pre-grinding guarantees a constant thickness, uniformity and surface quality of the carrier wafer.

The product wafer and the carrier wafer are glued to one another by a double-sided thermally releasable film. After thinning, the product wafer is detached from the carrier wafer again by the action of heat. At approximately 120 degrees Celsius, the double-sided adhesive film loses its adhesive power. When rolled up, this film can be stored with two cover films.

As the first product wafers, finger tip writing was thinned to 80 microns, 60 microns and 40 microns. The discs were sawn beforehand (bevel cut before thinning). In this case, the separated chips were then delivered on system carriers. The basic module of the device according to the invention is a vacuum chamber which is equipped for vacuum bonding two wafers. The device according to the invention for the plane connection of wafers makes it possible to treat carrier wafers on product wafers with a throughput of approximately 15 wafers per hour. The composite wafers produced with the device can still be handled in the extremely thin state of the product wafer. The product wafer on the composite wafer can be thinly ground to approx. 70 micrometers. A further removal of the product wafer can be done by etching.

The invention will now be explained in more detail by means of embodiments with reference to the accompanying figures.

FIG. 1 shows a schematic diagram of a device for the planar connection of two wafers to one another.

FIG. 2 shows a detail of a device for the planar connection of two wafers to one another.

FIG. 3 is a flowchart with the method steps of an exemplary embodiment of the method for the planar connection of two wafers for a thin grinding and a separation of a product wafer.

Figure 1 shows a schematic diagram of a device for the planar connection of two wafers 1, 2 to one another. In FIG. 1, reference number 3 denotes a vacuum chamber which is connected to an evacuation device for the chamber volume, not shown. The reference numeral 4 denotes a chuck, which is also connected to an evacuation device (not shown) and can receive a carrier wafer 2 on its surface 12. The reference numeral 5 shows a double-sided adhesive film which is connected in FIG. 1 with one of its adhesive surfaces to the carrier wafer 1. Numeral 8 designates a heater capable of heat the chuck 4 to the melting temperature of the double-sided adhesive film 5.

The vacuum chamber 3 is closed at the bottom by a vacuum base plate 29, the vacuum base plate 29 having a plurality of bushings. The feedthroughs 30 and 31 are current feedthroughs for the heating device 8 of the chuck 4. In the center of the vacuum base plate 29 there is a lifting rotary feedthrough 32 with which the height of the chuck can be adjusted and, if necessary, can be rotated. This lifting and rotating device has a pipe section 33, which at the same time leads as a vacuum line 34 to the evacuation device of the chuck 4, not shown, via a vacuum valve 22. The pipe section 33 can be ventilated inside via a ventilation opening 28 when the vacuum valve 22 is closed and the connection to the evacuation device is therefore interrupted.

The vacuum base plate 29 additionally has a pipe socket 35, via which the vacuum chamber 3 can be connected to the evacuation device (not shown) via a vacuum line 45 after opening the vacuum valve 7. The vacuum chamber 3 can be ventilated via a ventilation opening 27 when the vacuum valve 7 is closed. A tube piece 37 with a lower flange 38 and an upper flange 39, which forms a vacuum chamber wall 35, is arranged on the vacuum base plate 29. The lower flange 38 is connected in a vacuum-tight manner to the vacuum base plate 29 via a 0-ring 40. The upper flange 39 carries a vacuum chamber cover 18, which in turn is vacuum-tight with the upper via an O-ring 41

Flange 39 is connected.

A vacuum holding device 19 is arranged on the vacuum chamber cover 18, on the vacuum-side surface 20 of which a product wafer can be arranged with its rear side, so that the product wafer with its active surface 42 is suspended from the vacuum holding device 19 at a distance a from one another. μ- Ω μ- er • -d <P Pi PP \ -> CQ P> Pi P. <rt Di Ω Pf P Di m 3 <u er f ti P Pf er P =

3 ET CD μ- μ- PJ 3 μ- P Φ μ- Φ μ- P Cπ P Φ tu ti 0 er PJ P Φ ti μ- PJ P φ P P P P φ er

P rt P cQ Pf <! φ D. ti Ω CQ Φ Di ti ti Pf 0 d Φ P Pi P PJ: rt Pf ti μ- P P Di P P φ

IO Ω P. P P Φ E π> CQ Ω P Ω ti P CQ P Ω 3 CQ 3 Di ti

P Pf Di Φ li P P td 53 ET P rt D. li ET N P f φ Hi ~ H φ CQ P tr cQ ET CD Φ ET Φ

Φ J P 3 rt φ μ- PJ = P = • PJ 0 = P 3 ti H li er ti φ 3 φ J φ μ- J P

H Φ> N to f μ- H ii P Φ er CD tΛ er CD μ- ¹ μ- PH φ

CQ P N PJ P = Pi CQ Φ e • d Φ co PJ = P tu: CQ 1 μ- Pf Di ti Φ td ti ti rt φ Ω P CQ rt 21 P J PJ Ω rt P rt. ti

Ω PJ 53 N 3 Φ Hl Φ ii φ <ii * μ- PJ: μ- ET Pi Φ u PJ φ 3 CD E Φ ii <Φ O

ET P 3 Φ φ 3 P et er P Ti μ- u P P • d 53 rt φ - ti P Hi ti 3 <μ- PJ <N

P CQ μ- μ- μ- Φ P Φ D. ii Di f S 3 IJ Φ μ- P 1 D- Φ Φ> 0 0 Ω Pf 0 μ- 53 μ- Φ rt φ CQ li er. P μ- Φ 0 Φ CQ P μ- • 0 Φ li ^• li CQ Hi 2! ti PJ li P CQ li ET P ei φ φ et 0 H rt CQ 3 P Pi 3 P ii φ PJ Pi JJJ f Di 0 CQ H rt P i μ- rt H co ω CD P φ 3 Pi P - rt Φ Pf Φ Hi μ- et Φ ti Φ μ- P 3 μ- CJI rt

Di φ 21 Φ 1 0 = PJ Ti f <μ- <μ- P H CQ H Φ CQ P μ- Ω Di P Ω P <Ω φ

CQ P μ- PJ μ- u Hi P 0 et PJ Ω Φ PJ P: μ- 0 • Φ CQ ti Φ <f P Φ ET CQ Φ ET CQ P φ Φ P Hi PPP Hi CD CQ 1 Pf ET P r PP er T) er φ Φ Φ Φ 3 rt P rt φ

N rt φ φ Hi PP Ω μ- 21 P Φ r CD Φ Pi td φ ei φ t μ- μ- PPPP = rt P ET Pf φ ^ ti H ö Pi P Er rr JP 3 μ- ti Φ i co P 0 ti P <P tr μ- P PJ

H- φ Pi P μ- Hi 3 i 3 φ Pi Pi Hi <D. Φ Ω H Φ PJ CQ φ Q φ

CQ D- σ μ> et φ t CQ μ- O Φ 0 J P. H μ- φ P o 0 φ 3 er 03 μ- Pf ti et r rt Φ μ- PJ P t φ P li DP cn CQ JN CQ P f ti rt φ PPH cn H Φ φ ti Ω P μ- t IΛ> Φ Φ CQ • Ω rt et i Φ e ti μ- Φ PS £> Di S £> PP

S Pf P M μ] Pi! φ PJ 3 ti ii u <er • r] 1 φ CQ Hi CD ti 3 μ- 3 Di μ- ET Φ P- ü P P P μ- P & <td Φ Hi o 21 u rt t i CQ rt <! Pf φ μ- μ- 53 Φ ti μ- PJ: ti tr Di Hl rt <CQ f PJ • ti 0 PJ PJ: t, rt tU: <Φ PJ rt CQ φ P

D. Φ α to CQ Ω Φ Φ PJ ti P Pf Hi μ- Hl μ- P μ- PJ Ω Φ PJ PP <et ii ii Φ Φ tr μ- P Di CQ Pf 0 = Φ PP CQ φ Φ Ω Pi ω P ET CQ f et P PJ Φ Di Ω u PJ μ- ti μ- φ P Dt ⁾ ii 3 P u PJ = H ti ET μ- Ω D. Φ P μ- f H- Di Φ α ^ JPPP 1 Pi Q td Φ μ- P Φ 3 CQ Ω μ- σi co *>, CQ tr 3 PP = PP μ- P

Φ PHH φ 2. Φ Φ P 3 H <<J tr Ω Φ J .ι o = 3 tr P φ φ ii CQ Φ ti JP Φ & Φ ET Φ u Pi Φ <Φ ET <5 3 Pf φ P t CQ ET cn φ 3 ti CQ Pf m Hl

CQ Pi μ- H! μ- P = 0 ti J 3 f J P J P 0 μ- 0 = <ti J J ti μ- * Φ PJ

Ω Ω Φ P <φ PJ Ω Hi td HP CQ rt Pf 3 ti rt PJ PJ P CQ μ- tr φ PP PJ: tr ET 3 PJ 0 li P tr rr> du rt <P μ- P P. 0 = P Pf PN Φ Ω rt Φ Φ μ- μ- P = P Ω

P P P li CQ N Φ Φ Pf Φ PJ 3 P = P μ- CQ φ Φ P 3 P CQ ET Φ μ- rt Ω tr • tr

Ω μ- μ- P. ti CQ rr Φ P H et <f ET r 3 φ Φ μ- P μ- 0 Φ <! P = P P ET Φ Φ

Pf rt P φ μ- Φ Φ μ- CQ μ- 0 P PJ φ! CD μ- 3 P φ N ti P 0 Hl φ P rt li N rt ti Ω • d μ- et D- Φ <ti P ti μ- φ Ω φ Pi ti 53 Di P = φ ti rt CQ P D. φ > CQ • τ | • tr ti CQ μ- Φ μ- φ ti 3 et P P ET <ti μ- rt μ- P r μ- ti Φ td CQ φ H Φ

53 μ- et Φ Φ Q ti rr P μ- Φ P. P Ω - φ φ CQ Φ Φ P μ- et φ ll Φ μ- ii

Pf φ CQ α P cΛ P μ- Ω μ- <μ- Pi Pi er ü P. P Ω P ti φ Ω M ll 3 P td u μ- P Φ P rt Pi Q <CQ O ET P 0 Φ Φ Φ Φ er Φ NP tr> • P ET s: P = Φ Φ <J D-

P co ti ti CQ • φ φ J er et ti Pi μ ti ti μ- ti P Pi Φ μ- rt Φ Hi <μ- P PJ O

P φ P IQ Pf f Φ P D. ti <μ- Hi CD P P CQ φ T) P H rt Φ CQ f • d

HN Ω P ti P Φ μ- PJ φ <μ ⁴ rt Pi Ω <! φ 0 CQ ii P Di P ti rt TJ P • d

<: P ti P α ET P φ Hi CQ • i Ω Pf PJ PJ = φ er φ P Ti Φ 0 CQ Φ P tr Φ 0 μ- φ

0 P CQ PJ: 3 li 3 er ET P <Pf Ω P P Φ ti rt ti D. P D. P CQ P P ET φ

P D. Φ CQ P 0 Pf φ PJ: μ> <rt P PJ P ET tu li tr CQ 0- PJ Di P H CD P ti ti CD

N φ td Ω CD PJ P Ω sχ> PJ P 3 f P Φ Ω <Hi μ- PJ Di ^" CΛ f ID 0 = Di Dd CQ P Φ

Φ rt Φ ti? R CD 3 Di tr f PP 3 P ET u P CQ PN et Hi Φ <rt P μ- μ- Φ μ- 1 PJ Φ 3 φ Φ Hi P CQ φ P f Pf PJ: Pi et f D- P 1 PJ Hi P PJ P CQ rt

P μ- CQ 21 P μ- P Φ PJ = P μ- 3 PJ tu Di P Ω φ et Φ 21 P P Pf rt μ-

Φ H rt PJ Φ P Φ ti »τl J 3 μ> rt M 3 P μ- P tr P 53 t ti φ PJ PPN Di Q li ΪS φ Hi PP 0 P f ω P Φ 3 Hl Φ 3 Φ Pi φ 21 μ- Hl φ P α μ- Φ Φ

Φ P Φ Pi P = CD rt PJ P μ- Φ φ CD CQ P Φ ti PJ D. P Φ μ- CQ μ- φ P ti f

M μ- ti <φ <r μ- 3 PJ CQ rt ti μ- φ - Φ P Di Hl P φ ti P φ 1 μ- ¹

Φ CQ Φ ti J φ φ CD P 3 PPPH 1 i Φ Φ l 3 Φ to (J <Φ μ- Φ t ti Pf ti Φ PJ: Φ 1> P ω PJ φ P li Ω μ> 3 cn <co PJ 1

N 1 P cπ μ- 3 ti Φ »CQ P ti ET PJ 1 1 1 1 1 1 μ>

Device 8 are heated. Furthermore, the chuck 4 can be evacuated in the direction of arrow B, so that the carrier wafer can be held on the chuck 4 via vacuum bores 17. The exact positioning of the carrier wafer 2 on the chuck 4 is specified by means of positioning pins 23, 24, of which a positioning pin 24 is shown in this detail A. Such a positioning pin 24 can have a cylindrical shape as long as its length does not exceed the thickness D of the carrier wafer plus the thickness h of the double-sided adhesive film 5. In the embodiment shown in detail A, the positioning pin 24 has a conical shape and stands with its conical base surface 25 on the surface 12 of the chuck 4 and protrudes from the surface 12 with its cone tip 47. The conical design of the positioning pin 24 has the advantage that the cone tip 47 can contribute to guiding and positioning the product wafer.

The detail A also shows a partial cross section of the vacuum holding device 19, with which a rear side of a product wafer 1 can be held on the vacuum chamber cover 18, which is shown in FIG. 1. The vacuum holding device 19 is evacuated in the direction of arrow C, as a result of which the rear side 48 of the product wafer 1 is pressed onto the surface 20 of the vacuum holding device. For this purpose, the vacuum holding device has vacuum bores 17 which, in an embodiment not shown, can be machined into the vacuum holding device in concentrically arranged grooves. An exact positioning of the product wafer during the holding by the vacuum holding device and during the connection process of two wafers is achieved by conical guide pins 9 and 10, of which the conical guide pin 10 is shown in detail A. Its length bridges the distance a between the surface 42 of the product wafer and the surface of the double-sided adhesive film 5. The conical embodiment of the guide pin 10 ensures that when the product wafer falls onto the double film 5, which is adhesive on the skin side, prevents the wafer from tilting on the guide pin 10. In addition, detail A shows that the guide pin of the holding device 20 is arranged offset with respect to the positioning pin 24 on the circumference of the wafer, so that the pins do not interfere with the adhesive and connection of the product wafer.

Since the device which is shown in FIG. 1 has the possibility of adjusting the height of the chuck 4 via the lifting and rotating leadthrough 32, it can be of advantage to align the guide pins and the positioning pins precisely with one another, so that it is guaranteed is that a minimum distance a is guaranteed when the chuck 4 is raised in the direction of the vacuum holding device 19 and the two wafers 1, 2 are not accidentally pressed onto one another before the evacuation.

A further advantage of the device shown in FIGS. 1 and 2 is that the distance a can be varied during the process of connecting two wafers 1, 2 for thin grinding and later separation of a product wafer 1. Thus, the pumping cross section can be kept large at the beginning of the process by arranging the lifting device of the chuck 4 in its lowest position and before the product wafer 1 falls off, that is, as long as the vacuum in the vacuum chamber 3 is not yet the vacuum of the vacuum holding device 19 has reached, the distance a can be reduced to a few millimeters by lifting the chuck via the lifting rotating device 32. By moving the two surfaces to be connected, namely the active surface 48 of the product wafer 1 and the free surface of the double-sided adhesive film 5, the risk of the falling product wafer 1 tilting at the same or a higher vacuum in the Vacuum chamber 3 minimized compared to the vacuum of the vacuum holding device 19. FIG. 3 is a flow chart with the method steps of an exemplary embodiment of the method for the planar connection of two wafers for thin grinding and the separation of a product wafer 1. In a first method step 50, the first cover foil is removed from the two cover foils of a double-sided adhesive foil 5. In the next method step 51, the exposed surface of the double-sided adhesive film 5 can then be pulled onto the carrier wafer 2. This application of a double-sided adhesive film onto a carrier wafer can already be carried out fully automatically under vacuum. After the double-sided adhesive film 5 has been pulled onto the carrier wafer 2, method step 52 follows, in which the carrier wafer 2 with double-sided adhesive film between the pins or positioning pins 23, 24 on a chuck 4 of a semi-automatic machine, as shown in FIG 1 is shown, is inserted.

In the next step 53, the second cover film, which is still on the double-sided adhesive film, can be removed from the latter. For this purpose, the carrier wafer 2 can already be fixed on the chuck 4 by evacuating the chuck 4. In a step 54, the product wafer 1 to be ground is then sucked in between the pins or guide pins of the vacuum chamber cover 18 of the semi-automatic machine, as shown in FIG. 1. After closing and evacuating the vacuum chamber 3 in a step 55, the product wafer 1, which was held hanging by the vacuum holding device 19, falls onto the adhesive surface of the double-sided adhesive film 5. By venting the vacuum chamber 3 in method step 56, the product wafer becomes 1 with its active surface 42 placed on the carrier wafer 2 on top of the double-sided adhesive film 5.

After removal of the composite wafer formed in this way from a product wafer 1 and a carrier wafer 2 with an interposed double-sided adhesive film 5, further method steps can follow, which, on the one hand, provide grinding of the product wafer, a separation of product wafer and carrier wafer and a separation of the product wafer into chips. For this purpose, the wafer is thinly ground to <100 μm in method step 57, and the product wafer 1 is etched to a minimum of 40 μm in method step 58. These minimum 40 μm are not a limit, but are achieved in this implementation example. Thin etching can also be carried out over large areas down to thicknesses of 15 μm and below. Subsequently, the wafer composite of product wafer 1 and carrier wafer 2 with interposed double-sided adhesive film 5 is glued to the thinly ground wafer 1 on a saw frame stretched with film in method step 59. The product wafer 1 and the carrier wafer 2 are then separated by means of a heatable chuck 4 at, for example, 120 ° C. in process step 60, and finally the thinly ground product wafer 1 is sawed into chips in the saw frame stretched with a film ,

In addition to this implementation example of a method for the planar connection of two wafers for thin grinding and one

Separating a product wafer 1 into chips there are further variants which have already been described above. In particular, with the device according to FIG. 1, the pump cross-section can be varied in step 55 during the closing and evacuation of the vacuum chamber in that the chuck 4 is initially in a distant position from the vacuum holding device 19 by means of a lifting passage 32 in the vacuum base plate 29 of the device according to FIG. 1 is held and is moved into a position shortly before the product wafer 1 falls off, so that the distance a is only a few millimeters between the product wafer 1 and the carrier wafer 2.

The positions of the wafers of the positioning pins and the guide pins at the edges of the wafers can be variable and can be adapted to the size and shape of the wafers to be connected. The separation of the product wafer 1 into chips can take place before a separation of the product wafer 1 from the carrier wafer 2 take place, so that when the product wafer 1 is separated from the carrier wafer 2, only chips are still available for further processing. Other variations that are obvious to a person skilled in the art are possible without leaving the scope of protection of the attached claims.

Claims

claims

1. Device for the planar connection of two wafers (1,

2) one on top of the other, comprising: - a vacuum chamber (3) with an evacuation device for the olumen chamber, a chuck (4) with an evacuation device for receiving a carrier wafer (2) with double-sided adhesive film attached to the carrier wafer (2) on one side ( 5) or an adhesive layer, a heating device (8) for heating the chuck (4) and a vacuum chamber cover (18) with a vacuum holding device (19) for a product wafer (1) which is arranged in this way on the vacuum chamber cover (18) that the product wafer (1) is congruently arranged above the carrier wafer (2) before the product wafer (1) and carrier wafer (2) are connected at a distance (a) in the vacuum chamber (3) ,

Device according to claim 1, characterized in that the vacuum holding device (19) has guide pins (9, 10) which protrude perpendicularly from their surface (20) and are conically shaped.

3. Apparatus according to claim 2, characterized in that the conical base surface (11) of the guide pins (9, 10) is positioned on the vacuum holding device (19) and the cone tip (13) protrudes from the vacuum holding device (19).

4. Apparatus according to claim 2 or claim 3, characterized in that the guide pins (9, 10) of the vacuum Holding device (19) are arranged in the edge region (21) of the product wafer.

5. Device according to one of claims 2 to 4, characterized in that the guide pins (9, 10) of the vacuum holding device (19) with respect to the chuck (4) are arranged such that a precise and aligned storage and reception of the product Wafers (1) on the double-sided adhesive film (5) or on the adhesive layer of the carrier wafer (2) on the chuck (4) is ensured.

6. Device according to one of the preceding claims, characterized in that the device further comprises: a first vacuum valve (6) between an evacuation device of the vacuum holding device (19) and the vacuum chamber cover (18), a second vacuum valve (7) between the evacuator - iereinrichtung for the chamber volume and the vacuum chamber (3), a third vacuum valve (22) between the evacuation device of the chuck (4) and the chuck (4).

7. The device according to claim 1, characterized in that at least three guide pins (9, 10) are arranged on the vacuum holding device (19).

8. The device according to claim 1, characterized in that at least five guide pins (9, 10) are arranged on the vacuum holding device (19).

Device according to one of the preceding claims, characterized in that the guide pins (9, 10) have a length which is at least the thickness (d) of the product wafer (1) plus the distance (a) between the product wafer (1) and double-sided adhesive film (5) or adhesive layer and less than the distance between the surface of the vacuum holding device (19) of the vacuum chamber cover (18) and the surface (12) of the chuck (4).

10. Device according to one of the preceding claims, characterized in that the guide pins (9, 10) on their conical base surface (11) have a diameter of 200 to 1200 microns.

11. Device according to one of the preceding claims, characterized in that the guide pins (9, 10) on their cone tip (13) have a diameter of 100 to 500 microns.

12. Device according to one of the preceding claims, characterized in that the vacuum holding device

(19) has depressions (15) which can be connected to an evacuation device via a first vacuum valve (6).

13. The apparatus according to claim 12, characterized in that the depressions (15) are concentric grooves (16) which are formed in the vacuum holding device (19) and have holes (17) in their groove base, which with the evacuation device for the vacuum holding device ( 19) communicate.

14. Device according to one of the preceding claims, characterized in that the chuck (4) has positioning pins (23, 24) which protrude perpendicularly from the surface (12) of the chuck (4).

15. The apparatus according to claim 14, characterized in that the positioning pins (23, 24) are conically shaped and their cone base (25) is positioned on the surface (12) of the chuck (4) and the cone tip (13) from the surface ( 12) protrudes.

16. The apparatus according to claim 14 or claim 15, characterized in that the positioning pins (23, 24) of the chuck (4) in the edge region (14) of the carrier wafer (2) are arranged.

17. The device according to one of claims 14 to 16, characterized in that the positioning pins (23, 24) of the chuck (4) with respect to the vacuum holding device (19) are arranged such that a precise and aligned storage and reception of the product Wafers (1) on the double-sided adhesive film (5) or on the adhesive layer of the carrier wafer (2) on the chuck (4) is ensured.

18. Device according to one of claims 14 to 17, characterized in that the positioning pins (23, 24) of the chuck (4) have a length which is less than or equal to the thickness (D) of the carrier wafer (2).

19. Device according to one of claims 14 to 18, characterized in that the positioning pins (23, 24) relative to the guide pins (9, 10) in relation to the Edge (14, 21) of the wafers (1, 2) to be connected are arranged offset.

20. Method for the planar connection of two wafers (1, 2) for thin grinding and separation of a product wafer (1), the one wafer being a carrier wafer (2) with a double-sided adhesive film (5) or an adhesive layer and the second wafer is a product wafer (1), the method comprising the following method steps:

Pulling (51) the double-sided adhesive film (5) or the adhesive layer onto the carrier wafer (2), - inserting (52) the carrier wafer (2) between positioning pins (23, 24) or pins on a chuck ( 4) a vacuum chamber (3),

Inserting (54) the product wafer (1) between guide pins (9, 10) of a vacuum holding device (19) of a vacuum chamber cover (18) and fixing the product wafer (1) by opening a first vacuum valve (6) which the vacuum holding device ( 19) connects to an evacuation device, closing (55) the vacuum chamber (3) and evacuating the vacuum chamber to an equal or higher vacuum than the vacuum of the vacuum holding device (19) by opening a second vacuum valve (7), venting (56) the vacuum chamber ( 3) after closing the vacuum valves (6, 7, 22) and opening ventilation openings (26, 27, 28) while simultaneously pressing the wafers (1, 2) together due to the increasing pressure in the vacuum chamber (3).

21. The method according to claim 20, characterized by thin grinding (57) of the flat-bonded product wafer (1) to a thickness of less than 100 micrometers.

22. The method according to claim 21, characterized by thin etching (58) of the flat-bonded product wafer (1) thinly ground to less than 100 micrometers to a thickness (d) of up to 15 micrometers.

23. The method according to claim 21 or claim 22, characterized by separating the thinly ground product wafer (1) glued onto the carrier wafer (2) into individual chips.

24. The method according to any one of claims 9 to 12, characterized by heating the plane-connected wafers (1, 2) on a heatable chuck (4) to the melting temperature of the film (5).

25. The method according to any one of claims 20 to 22, characterized by gluing (59) of the thinly ground product wafer (1) with carrier wafer (2) on a saw frame stretched with film.

26. The method according to claim 25, characterized by separating

(60) of the product wafer (1) from the carrier wafer (2) over a chuck (4) heated to above the release temperature of the film or the adhesive.

27. The method according to claim 26, characterized by sawing

(61) of the product wafer (l) to chips.